THE FOOD SPRAY MANUAL Using the Food Spray Method to Enhance Biological Control in Cotton:
A Trainers’ Guide
Stephanie Williamson with Robert Mensah
Authors: Stephanie Williamson with Robert Mensah Layout: Susanna Acland Date of publication: October 2016
Published by PAN UK Pesticide Action Network UK The Brighthelm Centre, North Road, Brighton, BN1 1YD, United Kingdom D: +44 (0)1273 964233 M: +44 (0)7588 706224 W: www.pan-uk.org Company No: 2036915 Charity No. 327215
The material contained in this book can be freely copied and distributed provided full acknowledgement is made.
2
Preface Cotton is a tricky crop to grow and is notoriously pest-prone – a bad pest attack can devastate a crop. Many farmers rely on synthetic insecticides to control pests but these come with their own problems. Pesticide poisoning is rife: the World Health Organization estimates that around 3% of farmworkers experience at least one pesticide poisoning episode each year. This is almost certainly an underestimate. Surveys conducted by PAN UK in cotton growing areas of Africa and central Asia have uncovered poisoning rates of 30% or more. These poisonings can result in serious illnesses, and sadly, deaths from pesticide poisoning are not uncommon. The financial burden is also significant. The UN Environment Programme estimated that, the costs of injury due to pesticide poisoning in sub-Saharan Africa in 2009 were around USD $6.2 billion – more than the total aid budget for basic health care in the region. What is more, UNEP forecast that between 2015 and 2020 these costs will total more than USD$90billion. This is an enormous economic burden. The direct costs of pesticides are also large with many smallholder farmers spending half of their income on chemical inputs. Reducing reliance on pesticides makes sense from a health, environmental and economic perspective Luckily there is an alternative: Integrated Pest Management (IPM) – working with nature to keep pest levels down and using pesticides as a last resort – has been shown again and again to be an effective and economic way of controlling pests. IPM is a collection of approaches and its principles are deceptively simple: grow a healthy crop, use pest resistant crop varieties and deploy practices like crop rotations and good crop husbandry to prevent pest outbreaks. One key IPM approach is to use beneficial insects to keep populations of pest species down. Farmers can deploy various techniques such as planting companion crops to provide habitat to keep levels of beneficial insects high. Ten years ago, PAN UK began working with IPM expert Robert Mensah to develop a food spray, using cheap and locally available materials, to enhance populations of beneficial insects in smallholder cotton fields in Africa. Building on his pioneering work in Australia, and working closely with Davo Vodouhe and his team at OBEPAB in Benin, Robert conducted field trials and experiments in farmer’s fields to come up with a product that not only worked, but that farmers were comfortable using. By the end of 2012, nearly 2,000 smallholder farmers in Benin were actively using the food spray technique as part of their IPM programme. Their pesticide use (and costs) plummeted, while their yields remained comparable with conventional growers. In 2013, PAN UK and Robert took the technology to Ethiopia. This manual is the result of this project – working with
3
PAN Ethiopia, we carefully recorded every step of the process to capture key lessons and understand how to integrate the approach into farmer training programmes.
Today, thousands of cotton farmers are successfully using the food spray as part of their IPM systems. This manual is designed to allow hundreds of thousands more to benefit from the technology. It is aimed at sustainable cotton initiatives, project managers, extension agents, field trainers – anyone working with cotton growers world-wide. It guides trainers through each stage with helpful tips and advice from Robert, along with warnings of common problems and pitfalls. But a word of warning: The food spray is not a magic bullet. It is designed to work as part of an effective IPM system. It complements – not replaces – other IPM techniques and will only work if farmers are well trained and supported. That said, our experience has shown that the food spray is a valuable tool to control various cotton pests.
Keith Tyrell Director, PAN UK keith@pan-uk.org.uk
4
Acknowledgements This has been a long term project and over the years, has benefitted from the help and support of many organisations and individuals. We are very grateful to the JJ Trust for its long-term financial support for the technology, and in particular for funding the field trials in Ethiopia and the preparation of this manual. Similarly, TRAID’s support of our cotton projects in Benin and Ethiopia has been generous and long-standing. Funding from Frugi and the JAC foundation was indispensable at the early stages of the food spray development. None of this work would have been possible without the dedicated hard work of our partners on the ground in Benin and Ethiopia. The field teams of PAN Ethiopia and OBEPAB work tirelessly with farmers on the ground, day in, day out, and this manual is built on their practical expertise and knowledge. Similarly, the wholehearted support from the local Board of Agriculture in Arba Minch was essential to the success of the project in Ethiopia. The authors would like to extend their thanks to all of those involved in making the food spray project a success
5
Contents Foreword by Robert Mensah
Chap.1
10
Introduction to the food spray method and how it works
1.1
The rationale for the food spray method: better biological control
12
1.2
The three components of the food spray method
14
Component A. Manipulating the crop habitat Component B. Spraying the crop foliage with a food supplement Component C. Avoiding use of insecticides which will kill natural enemies 1.3
Some basic ecological science on how the method works
16
1.4
How the food spray method can contribute to better pest management
26
1.4.1 Experiences in industrialised countries: Australia
26
1.4.2 Experiences in African cotton: Benin; Ethiopia
29
1.5
Essential requirements for farmers to make effective use of the food spray method
35
1.6
Benefits from replacing hazardous insecticides
36
Chap. 2
Using the food spray method in practice
Section 2A. Preparing and applying the food spray
40
2.1 Different food spray ‘recipes’
41
2.1.1 How you prepare them
41
2.1.2 Adapting the recipe quantities according to the field situation
45
2.1.3 Pros and cons of the different recipes
47
2.1.4 Food spray preparation costs, compared with insecticides
49
2.1.5 Frequently Asked Questions on food spray preparation
52
2.2 How you apply the food spray
55
2.2.1 Equipment
55
2.2.2 Dose rates
56
6
Section 2B. Field monitoring, decision making and habitat management 2.3
2.4
Understanding about the balance between pests and natural enemies
62
2.3.1 The rationale behind the Predator to Pest ratio
62
2.3.2 A constantly changing balance requires frequent monitoring
64
Field monitoring to check on the Predator to Pest balance
65
2.4.1 Monitoring pests and beneficial insects: sampling techniques
66
2.4.2 FAQs about sampling and recording
69
2.5 Simple decision tools for smallholders
71
2.5.1 Calculating the balance of Predators to Pests
71
2.5.2 Making decisions based on the Predator to Pest balance
72
2.6 Making the habitat more favourable for natural enemies
76
2.6.1 The aims of managing the field habitat using trap crops
76
2.6.2 Which trap crops to use
77
2.6.3. How to plant trap crops
78
Chap. 3
Integrating food sprays as part of organic or IPM strategies
3.1 IPM principles and their relevance to using the food spray method
81
3.1.1 Principles of good crop husbandry for effective IPM
82
3.1.2 IPM principles for cotton
84
3.2 The importance of good cultural practices and field sanitation
85
3.3 When and how to make use of other IPM methods
86
3.4 Suitable direct control methods for bollworm or other key pests
88
3.4.1 Botanical extracts and commercial preparations
89
3.4.2 Biopesticides
91
3.4.3 Using light traps and pheromone traps
93
3.4.4 Other methods
95
7
Chap. 4
Ethiopian case studies on testing the food spray method and farmer training
4.1 Activities with smallholders
98
4.1.1 Smallholder farmer training and demonstration via Farmer Field Schools
99
4.1.2 Food spray trial treatments and lay-out
102
4.1.3 Monitoring of pests and natural enemies
105
4.1.4 Some summary results from FFS demo plots
108
4.1.5 Smallholder uptake of food spray method and IPM practices
112
4.2 Activities with large farms
116
4.2.1 Large farm demonstration and basic training via IPM pilot trials
116
4.2.2 Monitoring of pests and natural enemies
118
4.2.3 Results from large farms
120
4.2.4 Economic assessment and impact in large farms
123
4.3 Main findings and lessons learned
124
4.3.1 Main findings from the Ethiopian trials 2013-2015
124
4.3.2. Lessons learned
126
Chap. 5 Testing the food spray method with farmers 5.1
Trying the food spray method out as part of farmer training
131
5.2
Trial planning: objectives, lay-out and other design considerations
132
5.3
5.4
5.2.1 General issues in planning small, agronomic trials with farmers
132
5.2.2 Specific issues in relation to testing the food spray method
133
5.2.3 Considerations about food spray testing and experimental lay-out
137
5.2.4 Tips for trials in smallholder and large farms
140
Observations, data collection and entry
142
5.3.1 Field observations and insect sampling
142
5.3.2 Sampling in relation to food sprayed and control treatments
145
5.3.3 Data collection and data entry
146
5.3.4 Recording the data
148
Evaluating the food spray and control treatments 5.4.1 Making time-line graphs of pest and natural enemy numbers
8
149 149
5.5
5.4.2 How to make use of the Predator to Pest ratio data
152
5.4.3. Using the data for statistical analysis
153
Economic comparisons between integrated food spray systems and
155
farmers’ practice 5.6
Interpreting trial results and drawing conclusions
158
5.7
Testing the food spray method in other crops
160
Chap. 6
Lessons learnt and generating knowledge about the food spray method
6.1 Lessons from experiences in Africa
165
6.1.1 A viable organic alternative to high-input conventional cotton in Benin
165
6.1.2 A new basis for developing profitable organic and IPM cotton in Ethiopia
166
6.1.3 Ten lessons from testing and using the food spray method with smallholder 167 6.2 Expanding use of the food spray method
169
6.2.1 Relevance to other cotton production areas and systems
169
6.2.2. Crops other than cotton
170
6.2.3 Relevance in developed country agriculture
171
6.3 Generating new knowledge and sharing experiences
172
Annexes Annex I
Simple template form for insect recording for farmer training
174
Annex II
Conducting Agroecosystem Analysis in cotton
176
Annex III
(a) Beneficial insect assessment sheet
184
(b) Pest assessment sheet
List of acronyms
188
9
Foreword by Robert Mensah This manual is a guide to train farmers, extension agents and pest management professionals how to utilize natural enemies, mainly predatory insects which prey on pests, to support biological control and Integrated Pest Management (IPM) on cotton and other crops. It outlines some simple principles and strategies that can be used to attract beneficial insects from areas of native vegetation or landscapes surrounding farms into farmers’ fields, and then to conserve, sustain and utilize these natural enemies to help control pests. Beneficial insects, in general, form an integral and major cog in a healthy and truly integrated IPM programme. In a natural population, beneficial insects build up in response to an increase in food sources or availability, which, in many instances, are the host pests and the farmer needs to manage these beneficial insect populations effectively to enhance biological control. The natural dynamics of a farmer’s cotton cropping system is always limited because the pests usually arrive and attack the farmer’s crop first and by the time the beneficial insects arrive, the pests have invariably caused significant damage to the crops. Another drawback is that the cotton crop is an unnatural environment for beneficial insects and it is not a foregone conclusion that enough beneficial insects will colonise crops in the field during the crop growing stages. Through research and collaborations with cotton farmers, technicians, IPM professionals and charitable organizations (particularly the JJ Trust) and PAN UK, OBEPAB in Benin and PAN Ethiopia, two food spray products - Benin and Ethiopian Food Spray Products - have been developed. These products are maize and protein based food sources which have the ability to attract and sustain beneficial insects in cotton and other crops. As such, these locally made food products are key tools for use in any organic and IPM programmes in cotton and in food crops. This training manual provides a guide on how to use food spray products to develop healthy and successful organic and IPM programmes. The manual is also an educational tool that provides a clearer understanding of the basic elements required for a healthy pest management program. It will guide farmers, technicians and professionals on: 1. How to grow a healthy cotton crop 2. How to keep track of pests and beneficial insects (sampling techniques) 3. How to record pests and beneficial insects in your farm 4. How to preserving beneficial insects 5. Deciding when and how to control pests (decision making process)
10
6. Techniques for preparing and use of food spray products 7. How to use other IPM compatible tools and methods to encourage biological control The use of this manual is aimed at managing Helicoverpa species (cotton bollworms) and other pests in environmentally sustainable ways without the need for using excessive synthetic insecticides. The food spray product attracts and sustains beneficial insects while the other biological tools such as neem extract or soap are applied when the pest pressure becomes too great for the beneficial insects to cope on their own. Such a programme requires careful monitoring to maintain a good idea of the numbers of beneficial insects and pests present in the crop. This manual will provide practical guidance for those working with farmers to enable them to understand that observing and measuring numbers of pests and beneficial insects across the farm and making a decision based on the ratio of pests to beneficial insects helps in making better IPM decisions. I welcome this new training resource as a handy guide for organic and IPM farmers, technicians and professionals and commend it for your use.
Dr Robert Mensah Senior Principal Research Scientist (IPM, Biopesticides) Institute Director (& Technical Specialist on IPM for PAN UK and PAN Ethiopia) Australian Cotton Research Institute NSW Department of Primary Industries Narrabri, NSW, Australia
11
the food spray method and how it works
Chap.1 Introduction to
Chapter 1 Introduction to the food spray method and how it works In this first chapter, we explain in non-technical terms: ¬
The reasons for using the food spray method to increase natural, biological control of key insect pests in cotton
¬
The different components for putting the method into practice in farmers’ fields
¬
Some basic ecological science about how the method works
¬
Brief case studies describing how the method has been used successfully in industrialised and developing countries, on large and small farms
¬
Essential requirements for farmers to implement the method
¬
The benefits of using the food spray method in terms of safe, sustainable and profitable cotton
Detailed guidance is given in Chapter 2 on: how to prepare the different food spray recipes; when and how to apply food sprays; how to implement the other components in the method; and how to assess whether food sprays are working.
1.1
The rationale for the food spray method: better biological control
Making maximum use of biological control of pests is one of the fundamental principles of good Integrated Pest Management (IPM), for conventional farmers who want to reduce their reliance on expensive and often hazardous pesticides. Chapter 3 gives more information about IPM approaches and how the food spray method fits in. It is just as important for organic farmers, who are not permitted or do not want to use synthetic pesticides and who need to take full advantage of naturally occurring pest control processes. There are many beneficial insects, as well as other carnivorous animals, such as birds, bats, frogs and snakes, which feed on insect pests. These beneficial organisms are called natural enemies of pests and they perform, for free, the valuable ecosystem service of biological control.
12
Predatory insects and parasitic ones are important pest control agents in cotton, occurring
Trichogramma wasps which parasitize and kill the eggs of bollworms, or biopesticides based on specific fungi, bacteria or insect viruses, which infect and slowly kill their insect hosts. These biological control agents may be available as commercial or cottage-industry made products. Making good use of naturally occurring biological control is very important in sustainable cotton production, because: A healthy and active population of natural enemies can usually keep minor early season sucking pests, such as aphids, mirids, stinkbugs, mealybugs and whiteflies, from reaching problematic levels
Without natural enemies’ contribution to pest control, major pests like bollworm become more difficult and more expensive to tackle with synthetic chemicals alone
Relying to a large extent on synthetic chemicals as the main method for controlling cotton pests soon becomes unproductive, as the pests can rapidly develop resistance to the chemicals, plus activities of beneficial insects are disrupted, forcing the farmer to spray more often and at higher doses
An effective contribution of natural pest control helps farmers to reduce or eliminate their reliance on the highly hazardous insecticides commonly used in cotton and other crops, especially in developing countries, and therefore avoid harm to human health, wildlife and the environment
Many cotton supply chains, label standards, clothing companies and consumers are concerned about hazardous pesticides used by cotton farmers and want to buy safer, more sustainable cotton products Cotton farmers can often save money by shifting from insecticide-dominated pest control strategies to practices that encourage more biological control, while maintaining, or sometimes improving, cotton yield and quality
13
Chap.1
and minor pests under control. Other natural enemies can be brought in for extra control, e.g.
Introduction to the food spray method and how it works
naturally in and around farmland. If encouraged and conserved, they can help keep major
the food spray method and how it works
Chap.1 Introduction to
1.2
The three components of the food spray method
The food spray method involves enhancing (increasing) naturally occurring biological control of cotton pests by encouraging more natural enemies of pests into farmers’ fields. This is achieved by three, separate but linked components or farmer activities: A.
manipulating the crop habitat
B.
spraying the crop foliage with a food supplement (the ‘food spray’)
C. avoiding use of synthetic insecticides, especially in the early season, which will disrupt or kill natural enemies It is important to understand that the food spray itself is just one component of making the food spray method work. Component C is obviously much less relevant for organic cotton farmers but be aware that pesticides sprayed by neighbouring, conventional farmers could drift and affect organic fields. Some home-made botanical insecticides used by certain organic farmers may also be harmful to some natural enemies.
Component A. Manipulating the crop habitat The aim here is two-fold: (i) to help provide a refuge for natural enemies (ii) to serve as a “trap crop” for specific pest insects (mainly bollworms, but also mirid bugs) Providing a refuge: Insect natural enemies usually require some form of tall or dense vegetation to: shelter in from the rain, wind and midday sun: avoid getting seen or caught by the animals which feed on them: and provide a safe home for sleeping, mating and breeding. An open expanse of bare, dry soil with only small cotton seedlings does not provide a very inviting environment (habitat) for many natural enemy groups, especially in large fields or dryland cotton in the first half of the growing season. Nor will it contain many of their food source prey in the first few weeks after cotton germination. Natural enemies will therefore tend to stay in natural vegetation around the fields, in semi-natural habitats or in denser, mature crops nearby, unless the farmer takes actions to tempt them into the cotton field. Adding some form of field border vegetation and/or interspersing rows of taller crops attractive for predatory insects within the cotton field therefore helps provide more suitable habitat for natural enemies close to where the farmer wants them to feed- on the cotton pests. In the tropics, having one or two rows of maize or sorghum or four rows of alfalfa (lucerne) every few rows of cotton works well.
14
Serving as a trap crop: In the case of several bollworm pest species, such as African
stage, or on the sorghum head than on cotton. Farmers can take advantage of this behavioural preference to tempt female moths away from their cotton and onto maize or sorghum plants sown around the field edge or within the cotton. Other crops, e.g. lucerne (alfalfa), pigeonpea, sunflower may work to trap other bollworm species or other problem pests (mirid bugs) (see Chapter 4 on testing the food spray method with farmers). Trap cropping alone is very unlikely to provide adequate control of bollworms but it is a useful tool to include as part of an IPM strategy. Anything farmers can do to reduce bollworm egg laying in their crop and increase the predation of those bollworm eggs and small larvae that are present makes a welcome contribution to effective bollworm management.
Component B. Spraying the crop foliage with a food supplement Whichever food spray recipe is used (see Chapter 2), the ingredients when sprayed as a solution onto the cotton foliage give off a powerful odour which insects can detect from quite some distance away (up to 400 metres). Research and field experience has shown that food spray ingredients attract mainly PREDATORY natural enemies: ladybirds and other predatory beetles (from the Coleoptera Order); lacewings (from the Neuroptera Order); hoverflies (from the Diptera Order); predatory bugs (from the Hemiptera Order), amongst others. These natural enemies ‘home in’ on the odour, thinking that it is coming from their usual prey of small, soft bodied plant-feeding insects, such as aphids, leafhoppers, tiny bollworm larvae. Once in the crop, they start searching for these prey items and when they find them, they begin consuming them, thus performing the pest control service that the farmer wants. In cotton, it is essential to use food sprays to attract natural enemies into the crop very early in the season, so they are ‘ready and waiting’ before the major pests, such as bollworm, arrive. This helps keep problem pest numbers fairly low from the start, enabling the farmer to then reduce or possibly do without hazardous insecticides completely and use a range of other, safer (and often cheaper) IPM methods instead (see Chapter 3). One, single ‘ready in advance’ food spray application is very rarely sufficient to deliver the level of pest control needed season-long by IPM or organic cotton farmers. Farmers need to understand how to observe (monitor) the cotton crop regularly to check what the balance between natural enemies and pests is currently and to use simple decision tools to assess the situation in each field and decide on when a further food spray is needed or other suitable actions to take. These are covered in detail in Chapter 2.
Component C. Avoiding use of insecticides which will kill natural enemies There is little point in taking the time to prepare and apply food sprays to attract predatory insects, if you later spray a broad-spectrum insecticide which will kill the beneficial insects, as well as the pests! Unhappily, many of the cheaper, older insecticides readily available in
15
Chap.1
female moths much prefer to lay their eggs on maize when it is at flowering (‘tasselling”)
Introduction to the food spray method and how it works
bollworm Helicoverpa armigera, which feed as larvae on a wide range of crops, the adult
developing countries are equally, or more, toxic to natural enemies than to the pests they are the food spray method and how it works
Chap.1 Introduction to
aimed at controlling. Farmers are often unaware of this huge disadvantage of commonly used insecticides. Many cotton companies and agrochemical dealers routinely provide or recommend these older generation insecticides (organophosphates, organochlorines, carbamates, pyrethroids) which are simply not compatible with IPM. Even some of the more recent chemistry can be equally problematic for natural pest control, for example, neonicotinoid insecticides pose far higher toxicity to beneficial insects than many organochlorines. Some fungicides and herbicides can also be harmful. Using the food spray method therefore has to go hand in hand with awareness-raising about which pesticides to avoid, and with support for farmers to select less-toxic, preferably non-chemical, IPM alternatives.
1.3
Some basic ecological science on how the method works
For those interested in the detailed science and the research studies behind the development of the food spray method, a list of Robert Mensah’s key papers in the peerreviewed literature and other technical articles can be found in the Further Reading sections. Here we provide twelve Frequently Asked Questions (FAQs) and Answers to help explain the ecological science underlying the behaviour and interactions between insect prey and predator species in the field and how the food spray is best used to help manage pests in cotton. The method has not, so far, been tested in other crops although Ethiopian smallholders report trying it with good results in tomato! Chapter 5 provides guidance on how you can try out the method for yourself and evaluate the results.
16
Answer: No! Using food sprays helps to provide indirect control of cotton pests through the biological control of predatory insects feeding on these pests. The odour from the food spray attracts many of these predators into the cotton crop. The term ‘food supplement’ is probably more accurate than ‘food spray’ because by using this technology the farmer is encouraging more natural enemies into the crop so they can help keep pests from reaching damaging levels. It is very important for farmers to understand that the food spray is not toxic like a pesticide and does not kill anything- it is used like a ‘bait’ to tempt predatory insects into the cotton foliage, where they can then find and devour their favourite prey: pest eggs, small bollworm larvae, sucking bugs and other pests.
Question 2: How does it work to attract in the predators?
Answer: The food spray ingredients (whether based on protein-rich
ingredients such as brewers’ yeast or fermenting carbohydrates from maize, see Chapter 2) release volatile compounds in an odour ‘plume’ when they have been sprayed diluted in water onto cotton foliage, using a standard knapsack sprayer. We may not be able to smell these odours but many insects can! Many predatory insects ‘locate/ hunt’ their prey using smell, searching for and following characteristic chemical ‘signals’ which plant-feeding insects unconsciously release into their surrounding micro-environment when they are chewing plant tissue or sucking plant sap. In effect, the odours from the food spray particles coating the cotton plants ‘mimic’ these signals from prey species, such as aphids, and will grab the attention of predatory natural enemies foraging in the surroundings and attract them into the cotton crop, as they follow the odour trail to its source.
17
Chap.1
Question 1: Does the food spray kill pests?
Introduction to the food spray method and how it works
FAQs
the food spray method and how it works
Chap.1 Introduction to
Question 3: If the predators are attracted to the food spray odours, will they just eat the food instead of the prey?
Answer: No, not really. The diluted food spray does coat the crop foliage with tiny granules of the ground up solid product and predators may sometimes feed on a few of these granules, but maybe not enough to ‘fill their stomach’. The food spray granules mainly work to trick and bring the predators in, with the hope of available food/prey in the crop. Once the predators are attracted into the crop, the limited food granules then keep them hunting actively for prey where you want them - on the crop. The food spray smell makes them think prey is around so they will start searching and then find those pests that are actually there. Given a choice, these predatory natural enemies will always prefer to eat live prey, for its protein content, which they need in their diet and, especially, for egg development. They may also take a snack of something sugary, like nectar, for a quick energy boost at times.
Question 4: How do I know when to apply a food spray?
Answer: By careful, regular monitoring of the balance between pests and natural enemies, then using decision tools, as well as gaining experience. However, the first food spray of the season really needs to be applied on a crop growth stage basis, to make sure that predatory insects are already attracted into the crop early in the season before the pests arrive. Research studies and experience has shown that, in cotton, this is best done when the young cotton plants have reached 4 to 6 true leaf stage. Shortly after this stage, the plants begin to form squares (flower buds) which is the growth stage when the key bollworm pests start to arrive (so their offspring can feed on the developing buds and bolls). Exactly when the cotton plants reach 4 to 6 true leaf stage will depend on the cotton variety, growing conditions, weather and other factors, which vary from field to field and from season to season, so farmers will need to keep a close eye on the crop’s development. Further food sprays will be needed when the balance between predators and prey starts to swing back in the pests’ favour – how to monitor this balance and use the results to make food spray, or other, pest management decisions is detailed in Chapter 2.
18
Weather, crop growth stage, microclimate within the crop foliage, growing conditions, field location, cotton crop husbandry practices, especially pesticide use, on the farm or in neighbouring fields are among many factors that will influence how many pests and how many natural enemies will be present in a specific field at a specific time. This balance between predator and prey never stays static - it is continually changing as environmental and human factors change. Hence the need for careful, regular monitoring to assess the current balance (by calculating the ratio between Predators and Pests, see chapter 2B) and whether the balance is tipping towards more, or less, predators available to control the pests. Ideally, you want to use the three components of the food spray method to bring more natural enemies into the crop, earlier in the season than they might otherwise appear. You then want them to spend time hunting for prey, feeding heartily and feeling happy enough, with a nice, safe home, to mate and produce a new generation of bio-controllers living in and around your crop. Once the cotton crop is harvested, most of the natural enemies will then move out of the field to the surrounding bushes in search of prey. In the next cotton season, their offspring in nearby vegetation may move into the fields to look for prey but usually in low numbers at the season start. You will need to apply food spray again, when the cotton plants are small, to bring more predators into the crop in good time for the major pest arrivals. As you increase favourable farm habitat for natural enemies and reduce or stop using pesticides and introduce more IPM techniques, these practices will help to increase the natural, ‘background’
19
Chap.1
Answer: That depends on what is happening in and around your field.
Introduction to the food spray method and how it works
Question 5: How often do I need to apply it?
the food spray method and how it works
Chap.1 Introduction to
Question 6: How does the food spray affect pest species? Will it attract more of those into the crop too?
Answer: No, it does not serve as a chemical signal attractant to plant-feeding insects. Omnivorous and ‘neutral’ species (neither friends nor foes of the farmer) may be attracted at times and feed on some of the granules but not enough to disrupt the biological control process by the predators. There is, however, one important and useful effect on bollworm moth females, which adds value to the pest control service. Robert’s early studies noted a clear deterrence effect of the food spray on egg laying by female bollworm adults. In other words, the bollworm moths were laying fewer eggs on plots treated with food spray than with no spray or with chemical sprayed comparison plots. It seems that the powerful food spray odours ‘mask’ the chemical cues coming off the cotton foliage which female bollworms use when they are looking for suitable places to lay their eggs. African Bollworm is quite a ‘fussy’ pest and the females need to pick up the right chemical signals before they lay a proper delivery of eggs. If they don’t detect them, or not in sufficient levels, they may lay a few eggs only and move on. This deterrence effect on the key pest in cotton means the food spray delivers a double benefit: reduced bollworm egg laying + increased predator control action.
20
Answer: Over the years, various researchers have found that food supplements based on protein substances or on sucrose will definitely bring ladybird beetles and lacewings into food sprayed crops. When Robert developed the Envirofeast® food spray product in the late 1990s (see section 1.4.1 in this Chapter), he included ingredients to attract other predator groups too, including various beetle families and carnivorous bugs. The precise recipe of a food supplement, particularly its protein components, will determine which predator groups respond most positively. Field experience and Robert’s research has consistently shown that ants and spiders tend not to be attracted or affected by the food spray. Spiders can be useful predators of many pests, as can carnivorous ants (as opposed to the species which ‘tend’ aphids and actively protect these against natural enemy attack). Adult parasitic wasps (parasitoids) are not attracted either. As adults these wasps often feed on nectar (as do lacewing and hoverfly adults), while it is their larvae which form the carnivorous, ‘biocontrolling’ life stage. Using the food spray will not harm these other, nonattracted natural enemies. Providing favourable habitat via border and trap crop planting will certainly benefit them, as will avoiding broad-spectrum insecticides. So, indirectly the joint components of the food spray method also encourage and conserve other useful natural enemies.
21
Chap.1
natural enemies? What about parasitic insects?
Introduction to the food spray method and how it works
Question 7: Does the food spray attract in a wide range of
the food spray method and how it works
Chap.1 Introduction to
Question 8: Does the food spray method work to control all problem pests?
Answer: NO. The key predator groups attracted by food spraying, e.g. lacewings, ladybirds, hoverflies, are NOT able to prey on medium size and large caterpillars (Lepidoptera larvae). These predators are usually too small to be able to tackle caterpillars bigger than 7mm long (above 3rd instar stage, in entomological terms). So, for the key target pest of bollworms (most countries suffer more than one problematic bollworm species), the food spray component only works effectively against bollworm eggs and the first three larval stages (bollworm caterpillars will usually moult through 6 increasingly larger larval stages, known as instars, before they finish feeding and pupate) . In some places, there may be large predatory shield bugs or assassin bugs that will attack large larvae but the important point is that for bollworm control, the food spray method needs to target eggs and the smallest larvae. Farmers and field agents need to understand that applying food sprays to attract in predators simply won’t deliver effective control of larger bollworm stages. Once most of the surviving bollworm larvae are in their fourth stage, you need a different IPM control method for these (see Chapter 3). Putting the three components of the food spray method in place, in timely and careful fashion, along with other IPM practices, helps farmers gain control in the early to midseason. In Africa, Helicoverpa bollworm can often produce 2 or 3 generations during the cotton season, so focussing on minimising reproduction of the first generation early in the season helps to stop bollworm population levels spiralling out of control later.
Question 9: Can you ‘overfeed’ the predators, by applying food spray too often or too concentrated so they end up feeding on this rather than the pests?
Answer: NO. You can’t ‘overfeed’ because they will always choose the live prey if given the chance. However, it’s not a good tactic to apply food sprays when not needed, (a) because you’re wasting time and resources, and (b) excessive odour trails could end up confusing the predators and make it harder for them to locate live prey.
22
Answer: Attractant food spray ingredients do exactly that- by their odours, they attract predators into the crop and these natural enemies then start foraging for prey and soon find suitable food in the form of small, soft-bodied insects and their eggs- aphids, whitefly, leafhoppers, small caterpillars. Some predators, especially their larval stages, are voracious and may devour most of the pest prey items within a few days. If there are lots of predators feeding in the crop, at some periods they may find it (temporarily) harder and harder to locate the few remaining live prey, so they may decide to move elsewhere. The farmer, however, needs them to stay in the field throughout the growing season, to feed on newly arriving pests and freshly hatching ones. This is where an arrestant ingredient is useful – it ‘arrests’ the predators, i.e. keeps them in the crop, by providing a temporary, additional food source to encourage them to stay longer. Within a few days, the temporary scarcity of prey items usually ends, as new pests (or other prey) arrive and the offspring of earlier ones emerge. Adding sugar to a food spray recipe (whether the recipe is based on yeast proteins or fermenting carbohydrates, see Chap. 2A) works very well as an arrestant, as it provides a quick energy boost for hungry predators. Chapter 2A gives more information on the pros and cons of different recipes and when to use them.
23
Chap.1
food supplements for natural enemies. What’s the difference? Which do you use in the cotton food spray method?
Introduction to the food spray method and how it works
Question 10: I’ve heard about ‘attractant’ and ‘arrestant’
the food spray method and how it works
Chap.1 Introduction to
Question 11: I’ve read that using food sprays changes the ratio of natural enemies to pests. What does that mean?
Answer: Basically, it means tipping the balance between pests and natural enemies back in the farmer’s favour, so that there are enough natural enemies in his/her fields to contribute as much as possible to effective pest control. For cotton, Robert’s research and PAN project field experience shows that as long as there are at least half as many predators to pests (i.e. a ratio of 1 or more Predators to every 2 Pests) on a given date, this stops the pests getting out of control –at least for the next few days, and then you need to assess the situation again! How you monitor fields to assess and calculate the ratio is described in Chapter 2, in a simple way with smallholder farmers, and in a more technical way for extension agents in Chapter 5. Behind this ‘rule of thumb’ ratio there are a lot of biological and ecological processes and interactions going on and the sum total of these will result in the specific Predator to Pest ratio you observe on a particular day. These processes include: ¬ More predators attracted into the crop, and their increased searching activity, stimulated by the attractant ingredients in the food spray ¬ Increased predation (hunting) and consumption (eating) rates of predators, stimulated by the food spray attractant ¬ A longer time spent by predators in the crop, if arrestant ingredients are included in the food spray ¬ Possible reduction of any bollworm egg laying due to the food spray odours masking the chemical cues from the cotton foliage and confusing or deterring female moths ¬ Possible trap crop attraction of bollworm female moths away from the cotton and onto maize or sorghum plants for egg laying ¬ Reduced population levels of pest species as they are eaten before most of them can reproduce ¬ Possible reproduction of predator and parasitic natural enemies in and around the crop, thanks to the favourable habitat manipulation and avoidance of harmful insecticides, helping to maintain more biological control for longer
24
Answer: Costs and timings will vary, depending on national prices for inputs
and labour, choice of food spray recipe, availability of ingredients and equipment, and on the scale of your farm. Chapters 2, 4 and 5 will provide some guidance, with examples from specific contexts.
25
Chap.1
cost and how much time does it take to prepare and apply food sprays How does it compare with standard insecticide use?
Introduction to the food spray method and how it works
Question 12: You’ve convinced me! How much does it
the food spray method and how it works
Chap.1 Introduction to
1.4
How the food spray method can contribute to better pest management
In this section we briefly describe experiences to date in using the food spray method in organic and IPM cotton on small and large farms, as implemented by Robert Mensah and with PAN UK partners NGOs in Benin and Ethiopia. More details from the recent Ethiopian experience are given in Chapter 4, with useful context-specific guidance and broader lessons for people who would like to try the method in their cotton or other cropping systems.
1.4.1 Experiences in industrialised countries: Australia In the early 1990s, beneficial insects were totally neglected in the intensive pesticide use programmes common in Australian cotton production at that time. Worse, they were seriously harmed or killed, due to the disruptive effect of spraying broadspectrum insecticides, that included endosulfan. Bollworm and spider mite resistance to many insecticide groups was a growing problem. Average insecticide use frequency had reached 12-15 applications per season and often triggered secondary pest problems, such as mites, whiteflies, mirid bugs and aphids, which were expensive to control. It was high time to move to an IPM approach, built on a foundation of maximising the pest control role played by natural enemies. Cotton growers back then had no technique available to maximise the abundance and effectiveness of beneficial insects and other arthropods (e.g. spiders) in and around their fields. Based in the Australian Cotton Research Institute (ACRI), Robert had already experimented with lucerne (alfalfa) strips interplanted into cotton fields to serve as refuges for natural enemies and as a trap crop for one of the key Australian cotton pests, the green mirid bug Creontiades dilutus, a sucking pest. But he found that most of the natural enemies stayed in the lucerne and did not move into the cotton rows. Mowing the lucerne strips to try and ‘flush’ them out into the cotton rows caused both pests and beneficials to move but he ended up with lots of mirid bugs in the cotton, causing significant damage. He was therefore looking for a way to attract only the beneficial species from these lucerne strips into the cotton rows. Robert studied the literature from entomological research since the 1970s on attracting natural enemies using a variety of food supplements (see Chap. 2A for details). Over several seasons, he worked with a few committed growers who volunteered some of their fields for experimental plots, testing different combinations
26
of protein-rich and carbohydrate ingredients. He then trialled the most promising
effective food spray recipe to bring in predatory insects, which was then formulated commercially as Envirofeast® product by Rhone-Poulenc in 1998. Using Envirofeast® and lucerne strips as refuges plus trap crop, the growers who worked with Robert were able to reduce their use of synthetic insecticides by 40-60% without yield loss. Combining the food spray method with biopesticides based on bacterial and viral pathogens of bollworm, plus careful use of some considerably less toxic insecticides when needed, IPM growers could achieve similar yields and revenues to conventional neighbours. However, to make this transition, growers and their agronomist crop consultants both needed to: firstly, take active part in season-long, experimental plots on their farm, with the research team, to compare technical and economic performance in IPM plots with their conventionally managed fields learn how the food spray method worked and understand its ecological principles appreciate that ecological IPM techniques are not a ‘quick fix’ strategy like insecticides but require different monitoring and management skills gain experience and confidence over several seasons By 1999, the proportion of Australian growers adopting IPM strategies had increased from zero 5-8 years earlier to around 30%. Although many growers had started to accept and adopt the food spray method, this period coincided with the rapid uptake of transgenic B.t. cotton (Ingard ®), heavily promoted by the technology developer Monsanto and its agronomist advisors. Unfortunately, the biological control based IPM strategy was soon abandoned as the vast majority of growers came to rely on B.t. cotton to take care of their bollworm problems and insecticides to ‘clean up’ other pests. Demand for Envirofeast® then dropped and the distributors stopped marketing it but continued to hold the patent for the technology. From 2006 onwards, however, the Australian cotton sector started to revisit biological control strategies for several reasons: (a) the threat of bollworm resistance to transgenic (Bt) cotton (Ingard® and Bollgard II ®), (b) effective insecticide resistance management plans do not support natural enemy-based IPM programmes, and (c) cotton supply chains are demanding reduced reliance on pesticides. ACRI has been developing alternatives to synthetic insecticides, including fungal-based biopesticides, petroleum spray oils and plant extracts. Since
27
Chap.1
tandem with habitat manipulation using lucerne strips. By 1996 he had developed an
Introduction to the food spray method and how it works
ones at larger scale to refine this “invite and keep happy” strategy for predators, in
the food spray method and how it works
Chap.1 Introduction to
2012, Robert’s team at ACRI has been leading this work and some farmers are getting interested in the food spray method again, the reasons being that the food spray and biological options can be cheaper than relying on current expensive insecticides. The method can also work with B.t. cotton as its use allows enough time for the food sprays, beneficial insects and biopesticides to work without the urgent need to control bollworms with synthetic insecticides. The food spray method is now included as one recommended strategy in the annual cotton handbook [Australian Cotton Pest Management Guide]. To make the ecological IPM approach work in practice, Robert has identified the need to train a new generation of cotton farmers and agronomists in biocontrol-based IPM: those who grew up with transgenics and have poor ecological ‘literacy’ on conventional cotton. In 2016, his laboratory launched a new IPM-compatible botanical insecticide (called Sero X; see Chap. 3) as an additional tool for when direct intervention is required but which does not disrupt natural enemies. The future is now looking rosier for ecologically informed IPM in Australian cotton than it has for many years.
28
1.4.2 Experiences in African cotton
method would work in the context of organic smallholder cotton in African agroecosystems. PAN UK had been collaborating with local partner OBEPAB (Beninese Organisation for the Promotion of Organic Agriculture, in its French acronym) for more than a decade to, firstly, develop a pioneering organic cotton production system and, then, devise and deliver an effective farmer training programme and internal control system to enable trained farmers in village groups obtain organic certification for their cotton. The system was working well and farmer groups were exporting certified cotton to European customers, however, yields for most organic farmers were still lower than those achieved by good conventional farmers. OBEPAB wanted to find ways to improve control of African Bollworm in particular, beyond farmers’ use of home-made neem seed extract and some other botanical repellents, which provided some level of bollworm control but not sufficient in many situations. Robert helped OBEPAB to set up robust trials over a 4 year period to test the food spray method, to test whether it could improve yields and farmer income. Just as in Australia, biocontrol enhancement methods were needed to bring more natural enemies into the cotton crop each season. He first tested the commercial Envirofeast® product used in Australia and it certainly worked to attract predatory insects into organic cotton fields and to feed on pests and improve pest control. However, Envirofeast® was not available in Benin and, even if imported, it would be too expensive for smallholders to afford. The research therefore also developed alternative recipes for the food spray, using cheap, local resources. OBEPAB and Robert experimented with different recipes over two seasons, including yeast, sugar, and maize meal, to come up with an effective and affordable version, using waste yeast material from Benin’s breweries. Applying this food spray recipe to cotton foliage attracted beneficial insects into the cotton from the refuge/companion crops, such as maize or sorghum border or inter-rows, established as part of the organic cotton system. As in Australian large-scale cotton, the food spray works best when the first application is made early in the season before plants reach the 6-8 leaf stage. The Benin fieldwork showed clearly that following food spray application, predators’ consumption rate increases, leading to lower pest numbers, including bollworms and cotton stainer bugs- the two most important pests in cotton in Benin. Field trials with experienced organic farmers in 2007-2009 showed that using the yeast-based food spray method results in yield increases of more than 40% over farmers’ usual neembased methods, thanks to the enhanced biological control. The food spray odour
29
Chap.1
In 2006, PAN UK brought Robert Mensah to Benin to explore if the food spray
Introduction to the food spray method and how it works
Benin
the food spray method and how it works
Chap.1 Introduction to
and deposits on foliage and buds may also contribute by deterring egg-laying by bollworm moths, as Robert found in the Australian research. Further trials compared the economics of the food spray method in organic cotton with conventional insecticides as used in standard smallholder practice (often 6 recommended ‘calendar’ based’ sprays per season). Due to the much lower input costs of the food spray method, combined with the organic price premium, the highest gross margins were obtained using food spray and these exceeded by far the margins and return on investment from conventional insecticide regimes. However, there is a challenge to persuade non-organic cotton farmers to adopt the food spray, and other IPM methods, as they may perceive it as riskier than the insecticides. Refining the food spray method further and adding extra IPM tools compatible with organic practices (e.g. locally manufactured virus-based biopesticides) as well as use of neem seed extract, OBEPAB found the pest control results can be superior to control by insecticides. Yields using the food spray as the foundation for enhanced biological control increased as farmers became more experienced in using the technique. Seed cotton yields in excess of 900kg/ha are now possible using food spray plus other agroecological methods - not far off those that good conventional farmers achieve and better than those of the average conventional farmer (726kg/ha ) - but leaving organic farmers with much more money in their pockets. OBEPAB has since prioritised promotion of the food spray method, with the aim of attracting more farmers to the organic approach now that much improved yields are possible. By 2011, 1,700 organic cotton farmers had been trained, reaching almost 3,000 by 2015. However, many farmers have found it difficult to get hold of brewers’ yeast so OBEPAB has refined one of the carbohydratebased recipes, using part soaked and fermenting maize, then ground and dried to form as powder which the farmers nicknamed ‘Benin Food Product’. This is readily available to all smallholders as most of them grow some maize as part of the organic rotation but it is rather time consuming to prepare. It is not quite as effective as the yeast-based recipe because it lacks the ‘arrestant’ quality of protein ingredients, therefore farmers add a little sugar into the solution to provide temporary ‘snacks’ for predators. Chapter 2A describes the methods in detail. An essential component of the field research with farmers in Benin was to adapt the pest and predator monitoring protocol used by Australian farmers and crop advisors to a much simpler system which could be used by African smallholders with limited or zero formal education. Robert developed a simple, visual tool for farmers to assess the balance between pests and predators during field monitoring, using maize seeds for counting natural enemies and stones for pests.
30
The farmer then counts the maize seeds and stones to see if there are more than
training curriculum and has been adopted by organic cotton farmers (see Chap 2 for more information).
Organic farmers preparing the food supplement to attract natural enemies, Benin cotton zone. Credit: OBEPAB.
31
Chap.1
decision making tool has been integrated into OBEPAB’s Farmer Field School
Introduction to the food spray method and how it works
double the number of stones (pests) to maize seeds (natural enemies). This
the food spray method and how it works
Chap.1 Introduction to
Ethiopia Ethiopia’s southern Rift Valley is one of the country’s major cotton areas, grown by smallholders and also on large, formerly state farms, more recently under private ownership. However, production has been plagued by the usual problems of overreliance on broad-spectrum pesticides and lack of awareness of the role of natural enemies or other IPM and ecological principles. Cotton pest resistance to insecticides emerged recently in the Arba Minch area and some farmers responded by applying higher and more frequent doses, including Highly Hazardous Pesticides such as endosulfan, dimethoate, synthetic pyrethroids and chlorpyrifos. With the conventional pest management approach failing and agrochemical costs rising, cotton production was rapidly becoming uneconomical for many of the poor farmers in the Rift Valley, as well as less profitable for large farms. In 2012, PAN UK and PAN Ethiopia started a cotton IPM training project, funded by British charity TRAID, to address the human and environmental risks from conventional cotton and to help farmers change to IPM and organic systems, to improve farm family livelihoods and welfare. This three year Ethiopian project aimed to train 2,000 cotton farmers in the Arba Minch area of the southern Rift Valley in agroecological cotton production, including effective use of the food spray method. Since another UK donor, the JJ Trust, had supported PAN UK and OBEPAB’s training activities in Benin for several years, including adaptation of the food spray method, and now funded the food spray trial activities in Ethiopia. it made sense to share experiences from Benin. In 2013, two Beninese agronomists from OBEPAB visited Arba Minch to provide practical advice to their Ethiopian counterparts in PAN Ethiopia and crop protection staff from the regional Board of Agriculture’s Plant Health Clinic. A first season of field trials was set up in Farmer Field School learning plots in three village farmer groups, to compare different food spray recipes, with and without neem seed extract as a further IPM tool. Cotton prices and markets had slumped over the last two seasons, so most smallholders were no longer able or willing to afford insecticides, with less than 25% of farmers spraying their cotton. PAN Ethiopia, with smallholder FFS participants and the Board of Agriculture (BoA) collaborators, therefore decided to also include’ no spray’ comparisons in their field trials as a better reflection of untrained smallholder practice, which was delivering disappointingly low yields. Results from all of the food spray treated plots were very encouraging in the first season. Robert Mensah visited in 2014 and 2015 to provide training for the technical staff on the science and practice of the food spray method and guidance on broader cotton management. Food spray trials were repeated in three FFS groups in the
32
2014 seasons, again trying out the ‘Benin Food Product’ recipe, using maize, and a
large increase in yield compared with smallholder current practice. Again, in 2015, FFS learning plots in 8 villages showed considerable yield increases, up to double the yields of untrained farmers, in IPM plots using the food spray and good cotton crop management, with zero insecticide use. Some farmers trained in the 2013 FFS were now using the food spray method successfully on their own farms and even trying it out on some of their vegetable and cereal crops. While smallholders had moved away from insecticide use, large farms continued with chemical control, using 4-6 applications per season, predominantly of endosulfan, despite it having been recently added to the Stockholm Convention Persistent Organic Pollutant (POP) list for global phase out. After inviting them to the 2013 FFS open day, in which the preliminary results from the first season of food spray trials was presented, the project persuaded the technical managers of two large farms to provide a small area for PAN Ethiopia and BoA team to carry out an IPM trial, comparing the food spray method with an unsprayed control and each farm’s current insecticide regime.
Maize inter-rows planted before cotton provides a refuge for natural enemies to build up numbers before the main pests arrive. Credit: PAN UK.
33
Chap.1
all the food spray treatments, with high numbers of predators attracted in and a
Introduction to the food spray method and how it works
yeast recipe, obtained from a national brewery. Excellent results were obtained with
the food spray method and how it works
Chap.1 Introduction to
In 2014, the first trial on large cotton farms took place, with results suggesting that enhancing natural biological control of key cotton pests can work well to establish a sound foundation for more ecological pest management in large scale farms. However, it will almost always be necessary to make further IPM interventions in the large farms to achieve good yields. Results from 2015 trials confirmed the effectiveness of the food spray method in delivering yields similar to those of conventional insecticides, under good agronomic practices, with equal or better net revenue. Yields on all the IPM treatment plots, including the control treatments, were considerably higher than those on the farms’ main fields, indicating that effective and profitable cotton pest management also needs careful attention to field hygiene and good cultural practices, as well as the specific methods to enhance natural enemy contribution to pest control. Results from the large farm trials have been analysed and a paper is currently in press (see Further Reading). Robert continues to provide technical support to the trials, with plans to assess the effectiveness of light trapping and pheromones on the large farms from 2016, along with targetspecific insecticides more compatible with IPM, so that HHPs can be phased out.
Ladybirds mating on cotton leaf, Ethiopia. Farmers can gain extra pest control benefit when natural enemies reproduce in or around the cotton crop. Credit: PAN UK.
PAN Ethiopia and partner NGO, the Institute for Sustainable Development, are disseminating the food spray method for use in household and smallholder vegetable growing, through the high school ‘Environment Clubs’ which ISD supports in Arba Minch and Ziway towns. PAN Ethiopia plans to experiment with the method in smallholder vegetable production in the Lake Ziway area, which is infamous for frequent application of a cocktail of HHPs. Through PAN UK contacts with organisations supporting smallholder vegetable IPM projects in India and Malawi, those projects are also keen to try the method out in their agroecological contexts.
34
1.5
are to be able to implement the method successfully in their fields. The following list summarises the knowledge, ecological understanding and field monitoring and decision making skills which farmers need to put the food spray method into practice: a) Be able to distinguish their main cotton pests and important natural enemy groups (e.g. ladybird beetles; lacewings, hoverflies) including in the larval, as well as the adult, stages
b) Carry out regular field monitoring, ideally twice a week, in a small sample of plants in each of their cotton fields, to assess the numbers of pests and predators present
c) Understand how to use their field monitoring results to take decisions on which pest management actions they need to take next, using very simple decision tools designed for smallholder farmers with limited education
d) Prepare or obtain a suitable food spray and apply it carefully and at the right times during the season
e) Understand what the food spray method can and can’t do and how to combine it with other IPM methods For farmers to be able to implement this safe, low cost and effective IPM tool, they need to be trained in: basic insect identification skills field monitoring methods for pest and beneficial arthropods (insects, spiders and mites) decision making using the Predator to Pest ratio decision tool This also requires trained and confident trainers, whether government agricultural extension staff, NGO field agents or others, already with some experience of using the food spray method. Chapter 2 provides details of the field monitoring methods for smallholders. In Chapter 5 more guidance on farmer training is given and lessons from the Ethiopian experiences.
35
Chap.1
Readers will appreciate from the sections above that farmer training is all important if they
Introduction to the food spray method and how it works
Essential requirements for farmers to make effective use of the food spray method
the food spray method and how it works
Chap.1 Introduction to
1.6
Benefits from replacing hazardous insecticides
It should also be clear that by implementing the food spray and other ecological pest management methods, whether in a fully organic or an agro-ecologically sound IPM strategy, cotton farmers, their families and farm workers can derive important benefits socially, economically and environmentally. By phasing out the use of Highly Hazardous Pesticides (HHPs) still widely used in conventional cotton production, farm family and worker exposure to harmful products is minimized. PAN UK, OBEPAB and PAN Ethiopia have all published reports on the health hazards, risks and poisoning incidents associated with the use of HHPs in cotton, most notably endosulfan. Frequent use of toxic insecticides in cotton production zones, using risky practices, such as washing knapsack sprayers in water courses, often generates negative environmental impacts too. These impacts include: o
Unintentional poisonings of valuable livestock
o
Harm to beneficial organisms, including natural enemies, bees and soil life, which, unharmed, deliver important ecosystem services of natural pest control, pollination, nutrient cycling and maintenance of a healthy soil structure
o
Harm to biodiversity, such as fish, wild bees producing honey, animals providing bush meat and other flora and fauna which contribute food and income to resource-poor, rural people
o
Contamination of surface water, ground water and wells which are used for drinking water, washing and swimming by rural communities and their animals
Pesticide- related poisonings and other harm to human health, animals and the environment also carries a direct economic cost to those affected and to public services, such as health clinics, when they have to treat those suffering acute or chronic poisoning. A recent study by the UN Environmental Program estimated that between 2005 and 2020, the accumulated cost of acute illness and injury linked to pesticides in small scale farming in sub-Saharan Africa could reach US$90 billion, if no action is taken to control hazardous pesticides and poor practices. To put this in context, donor aid to basic health services (excluding HIV/ AIDS) in sub-Saharan Africa was around $4.8 billion in 2009. The UNEP estimate does not include any potential chronic health effects of current exposure patterns.
There are also huge economic benefits for cotton farmers in moving away from reliance on HHPs and towards more ecologically sustainable strategies for managing cotton pests, diseases and weeds. Pests, such as bollworms, developing resistance to entire classes of frequently sprayed chemicals is a major and recurrent problem throughout the cotton
36
growing world, which makes crop protection more expensive and more difficult for
more problematic and their control adding to cotton production costs. Last but not least, a growing number of textile companies, clothes retailers and others in cotton supply chains are responding to consumer concerns about pesticides and looking to source safer and more sustainable cotton, which does not harm farmers or workers. By using the food spray method cotton farmers and projects which work with farmer groups can take a big step up the IPM ladder to cotton production based on ecological principles. Chapter sections 2A and 2B describe in detail how to put the food spray method into practice.
A facilitator supports farmers while monitoring the crop for insect pests and natural enemies. Credit: PAN Ethiopia.
37
Chap.1
up with secondary pests, notably whiteflies, aphids and jassids (leafhoppers), becoming
Introduction to the food spray method and how it works
farmers. By killing off valuable natural enemies, high insecticide use strategies often end
the food spray method and how it works
Chap.1 Introduction to
Sources of information Hidden costs of pesticide use in Africa. Food & Fairness briefing no.2, PAN UK, 2007. Via: http://www.pan-uk.org/publications/food-fairness-briefings Synthesis Report for Decision-Makers - Global Chemical Outlook: Towards Sound management of Chemicals. United Nations Environment Programme, 2012. Via: www.unep.org/ hazardoussubstances/ Participatory cotton IPM in Australia. In: Learning to Cut the Chemicals in Cotton. Case studies and exercises in farmer focused cotton IPM from around the world. PAN UK and CABI Bioscience, 2000, pp. 47-53. E-version available via PAN UK. Productive and profitable organic cotton – Benin. Stephanie Williamson and Davo Simplice Vodouhê (2015). In: Replacing Chemicals with Biology: Phasing out Highly Hazardous Pesticides with agroecology. Meriel Watts with Stephanie Williamson, PAN International, 2015, Chapter 7.1, pp. 113-124. Available via: http://www.panap.net/sites/default/files/Phasing-Out-HHPs-withAgroecology.pdf A new tool for improving organic cotton yields in Africa. Davo Vodouhê et al. (2009) Pesticides News 84 6-9. Via: http://www.pan-uk.org/pestnews/Issue/pn84/PN84_6-9.pdf Food spray training in Benin – a recipe for success. Eliza Anyangwe (2010) Pesticides News 89 p.7. Via: http://www.pan-uk.org/pestnews/Free%20Articles/PN89/PN89_p7.pdf R.K. Mensah, D.S. Vodouhe, D. Sanfillippo, G. Assogba and P. Monday (2012). Increasing organic cotton production in Benin West Africa with a supplementary food spray product to manage pests and beneficial insects. International Journal of Pest Management 58 (1)53–64
Amera, T, Mensah, RK and Belay, A. (2016) Integrated pest management in a cotton-growing area in the Southern Rift Valley region of Ethiopia: Development and application of a supplementary food spray product to manage pests and beneficial insects. International Journal of Pest Management (In press).
38
Useful reading
Development Corporation Publications, Narrabri, NSW, Australia Cotton Pest Management Guide 2015-2016. CottonInfo, Australia (150 pp.) Available via: www.cottoninfo.net.au
39
Chap.1
Guidelines 2nd Edition). R K. Mensah, L. Wilson and S. Deutscher (1997) Cotton Research &
Introduction to the food spray method and how it works
The Integrated Pest Management Guidelines for Australian Cotton Production Systems (, IPM
This Chapter provides more detailed guidance, with examples, on how to use the food spray method in the field, in either IPM or organic cotton systems. applying the food spray
Chap.2A Preparing and
Chapter 2 Using the food spray method in practice
2A. Preparing and applying the food spray Section 2A covers practical aspects of food spray preparation and application including: Some different food spray ingredients, plus the pros and cons of each
How to prepare two main food spray ‘recipes’
How to apply the food spray onto crop foliage
Aspects to consider when choosing a suitable food spray recipe Section 2B covers the field monitoring and decision making aspects and the habitat management component of the food spray method: The system for deciding when to apply food sprays
How to monitor the crop to assess the balance between pests and natural enemies
Simple field monitoring and decision making tools for smallholders
Different ways to make the field habitat more favourable for natural enemies The focus in this chapter is mainly on using the food spray method with smallholder farmers. Its use in large farms and for trial purposes by technical staff (researchers, extension workers or NGO field agents), with dedicated personnel conducting field monitoring and assessment, is covered in Chapters 4 and 5.
40
2.1
Different food spray ‘recipes’
As mentioned in Chapter 1, entomologists have known for many years that certain food substances can work to attract natural enemies into farmers’ fields for biological control purposes. Most of the research was done in the 1970s and, apart from Robert’s work, little has been done since to turn this knowledge into a practical IPM tool. In this section, we
Chapter 5. Towards the end of this section we discuss issues for cotton projects to consider when deciding which of the proven recipes will be most suitable for farmers in their context.
2.1.1 How you prepare them YEAST-BASED RECIPE This is the recipe that Robert and OBEPAB first used as a local ‘home-made’ alternative in Benin to the commercial Envirofeast® product he had developed and used with Australian cotton growers. Food products based on yeasts are rich in protein compounds and these work well to ATTRACT predatory insects into the field. One of the best and cheapest sources of suitable yeast-rich material is the waste yeast from breweries after they have fermented the cereal grain ingredients for beer brewing. Only part of the yeast produced during fermentation can be recycled for the next production batch so the other part becomes a waste product for the breweries and they should therefore be willing to provide it for free or very cheaply. This ‘spent’ yeast is very high in protein and B vitamins and is sometimes given to livestock as a feeding supplement. Waste brewers’ yeast comes as a solid or semi-solid or powdery material, which can be stored for some time without decomposing. Research and field experience has shown that adding sugar into the food spray ingredients helps to ARREST predatory insects in the crop, by providing a temporary, high energy food source for a few days if prey numbers drop. The recipe therefore includes the yeast ingredient as an attractant and sugar to keep the predators in the crop for longer, if prey numbers temporarily fall. Also, to some extent the dissolved sugar helps as a sticker so the food spray is not easily washed off the plants after rain.
41
Chap.2A
has collaborated. Brief guidance on experimenting with different recipes is given in
Preparing and applying the food spray
only describe ingredients and recipes used by Robert and PAN partners with whom he
The method for preparing food spray from waste or “spent” brewers’ yeast is very simple: basically mixing it and diluting it in water, then filtering to remove the bulk of the solid material and using the remaining liquid, which now contains tiny yeasty
The ‘recipe’ used in the Ethiopian project trials for the yeast-based treatment was as follows: applying the food spray
Chap.2A Preparing and
particles, as the food spray.
Quantities sufficient to apply one yeast-based food spray to 1 hectare of cotton Step 1) Mix 1kg of brewery yeast waste (or if the yeast is in solution use 1 litre of the yeast solution) in a bucket with 5 litres of water to make your basic food spray ‘concentrate’ Step 2) Carefully filter out the solids, using a fine kitchen sieve or a piece of muslin cloth Step 3) Add approx. 50-60 grams of household solid soap, cut into small pieces, to the remaining liquid, plus 1kg sugar The soap is added as a ‘sticking agent’, because it helps the spray stick to the cotton foliage. Soap also contains salts and fatty acids which act as a selective pesticide for small, soft-bodied, rather static insects, e.g. aphids and other sucking bugs, spider mites, and their eggs. Soap-based material is sometimes sold commercially as insecticidal soaps and these are compatible with IPM and organic practices. The soap compounds act on contact and must be applied directly to the insect to be effective, by physically disrupting the insect’s skin (cuticle) or blocking its breathing holes (spiracles). Beware that frequent application of soapy solutions over a short period can damage the crop by drying out the leaves.
42
MAIZE-BASED RECIPE As the Benin food spray trials and farmer training progressed, PAN UK’s partner OBEPAB and the farmers felt it was too difficult to reliably get hold of brewery waste in the volumes they needed for all the trained farmers. With Robert’s guidance, they
alternative. The preparation method for the maize-based food spray comprises more steps, is more labour-intensive and takes considerably longer (3 days) than the yeast-based recipe to end up with the final product. It requires the maize to start partial fermentation in order to work, via (i) the predator attractant odour from the fermenting grain, and (ii) helping to mask the volatile chemical signals released by cotton plants naturally, which are attractive to plant-feeding pests. Quantities sufficient to apply one maize-based food spray to 1 hectare of cotton A) Preparation of “Benin Food Product” Step 1) Prepare and clean maize, using 4kg maize kernels for each hectare’s worth of spray required Step 2) Boil 10-15 litres water separately per 4kg batch of maize Step 3) Add boiling water to maize in a bucket and soak for 24 hours in a dark place Step 4) Use a sieve or fine meshed cloth to separate the soaked maize from the water Step 5) Crush and finely grind the soaked maize kernels using a hand-powered mortar or other equipment Step 6) Add 8-10 litres cold water to the crushed maize and leave for 48 hours Step 7) Filter out the crushed kernels using a sieve, then spread out and dry this solid mass in the sun. You are aiming to produce a coarse, dried powder. This has become known as ‘Benin Food Product’ (BFP). NOTE: there will be unavoidable wastage and loss of some of the maize during Steps 1-7. On average, the ‘conversion rate’ from raw maize kernels to dried BFP powder is 2 to 1, i.e. you need to process 4kg of raw maize to end up with 2kg of BFP powder for use on 1 ha.
43
Chap.2A
northern cotton zones of Benin, hence the move to maize-based food spray as an
Preparing and applying the food spray
therefore looked for ingredients which were more readily available in the remote,
Step 8) The sun-dried powder is then ready for diluting with water as a food spray solution. B) Preparation of “Benin Food Product” food spray
water to make your basic BFP ‘concentrate’ Step 10) Carefully filter out the solids, using a fine kitchen sieve or a piece of applying the food spray
Chap.2A Preparing and
Step 9) Mix 2 kg of dried ‘Benin Food Product’ powder in a bucket with 5 litres of
muslin cloth Step 11) Add approx. 50-60g of household solid soap, cut into small pieces, to the remaining liquid, plus dissolve in 1kg sugar
NOTE: If pouring food spray concentrate directly into a knapsack sprayer for dilution with water in the spray tank, make sure that the sprayer was not contaminated with insecticide from earlier use.
Training session on the preparation of the Benin Food Product spray ingredients. Credit: PAN Ethiopia.
44
2.1.2 Adapting the recipe quantities according to the field situation Robert’s experience has shown that it makes sense to make adjustments to the food spray ingredients, volumes used and dose rate, according to the individual field situation of predator and pest balance. There are no hard and fast ‘rules’ about how to do this and it is largely a matter of gaining experience, along with careful field monitoring. Here we
Volume of yeast or maize-based ingredients: The correct rate used for the commercial Environfeast ® product in Australia was 2.5kg per ha. During the trials in Benin we looked at various rates and found that anywhere between 1-2kg (or in solution 1-2 litres) of either the yeast-based or maize-based ‘product’ will work to attract predators in.
Robert Recommends: Robert’s advice is that if your predator to pest balance is nearing the unfavourable level of more than two pests for every predator (Predator to Pest ratio between 0.45-0.50, see section 2.5 in Chap. 2B) you can use the 1kg rate but if it is less favourable (i.e. below 0.45 Predators per Pest) then you need to use the higher rate of 2kg per ha.
The idea of the food spray is to cover the leaves of the cotton plants and attract more predators in before the pest arrives. In the beginning (early season), you will need more odour in your cotton crop to get more attraction effect. So if you apply 2kg for dilution in a 15 litre knapsack, the food spray concentration is high, with a powerful odour plume and you are arresting attracted predators with the added sugar. The next food spray is to cover the new leaves and ‘top up’ the food spray on the older leaves (cumulative effect of the doses) so you may not need a very high dose to do this and 1kg of food spray product should be enough, unless your Predator to Pest balance is very unhealthy. If the Predator to Pest ratio is below 0.45, you can repeat the 2kg rate used in the initial spray of the season.
45
Chap.2A
make.
Preparing and applying the food spray
provide some basic guidance on the situations you may face and the adjustments you can
Need for and volume of sugar for emergency food supply: If your monitoring shows that you have pests in your field already, you need only to attract the predatory insects into your crop and when they find this prey they will stay and feed on it. However, if you have no or very limited numbers of prey then you need to add an arrestant in the form of sugar to provide a temporary food source for the natural enemies. Within a few days there will be some pest eggs laid or new adults emerging or flying in, for the predators to feed on so you just need to keep them going on the emergency food until applying the food spray
Chap.2A Preparing and
This situation can occur if predators have been very effective and eaten most of the prey.
this happens. You can add 1kg of sugar into the food spray mix at step 3 in the yeastbased recipe or step 11 in the maize-based recipe. Experience shows that 1 kg sugar per ha is generally enough. The more sugar you add, the longer you may keep the predators in the crop IF there are few pests for them to prey on. Adding more sugar starts to increase the cost of your food spray. There is no point in adding more than 2kg max in the food spray mix.
NOTE: for your first food spray of the season, at 4-6 true leaf stage of the cotton, there may be very few or no pests for predators to feed on. You want to attract the predators in so they are ‘ready and waiting’ for when the first pests appear, so you will definitely need to add sugar into this first, crop stagebased food spray application. If you don’t, you run the risk your invited predator guests will soon get hungry and move elsewhere to look for food!
Robert Recommends: In general, for a beginner user of the food spray method, Robert’s advice is to use the higher rates of food spray product (i.e. 2kg per ha) until you gain experience.
46
2.1.3 Pros and cons of the different recipes and FAQs' Table 2A.1 below presents the advantages and disadvantages of using the yeast-based versus the maize-based recipe. Farmers and support organisations planning to use the food spray method need to discuss these and the issues arising in the Frequently Asked Questions and think carefully about which makes most sense for their particular situation.
Yeast-based using
Maize-based using BFP
characteristics
brewery waste
recipe
Quick to prepare from
YES. Can be made up
NO. Requires 48 hours+
the raw materials?
within a couple of hours
preparation
Simple method, once
YES.
YES.
YES, if obtained for free or
PARTLY, especially if
a minimal ‘fee’ (but maybe
farmers grow their own
some transport cost)
maize anyway
Easy for smallholders to
NO, unless part of a
YES.
obtain?
project or farmer
farmers have been trained? Low cost?
association that can get supplies direct from the brewery Raw material can be
YES, up to a month. Do not
YES, up to a month.
stored for a few weeks?
add sugar when the yeast is
Sugar is added when
in storage. Sugar is added
recipe is ready to be
when recipe is ready to be
sprayed out.
sprayed out.
Easy to use in the
PARTLY, as long as solid
PARTLY, as long as solid
knapsack sprayer?
material is carefully filtered
material is carefully filtered
out of the food spray
out of the food spray
solution
solution
YES.
YES.
Works well to attract predators into my crop?
47
Chap.2A
Desirable
Preparing and applying the food spray
Table 2A.1 Pros and cons of yeast-based and maize-based food spray recipes
applying the food spray
Chap.2A Preparing and
Works well to keep
NO. Requires sugar or
NO. Requires sugar or
predators feeding in the
other ‘arrestant’ ingredient to
other ‘arrestant’ ingredient to
crop if pest food supply
be added OR more frequent
be added OR more frequent
drops temporarily?
application
application
Needs a sticking agent
PARTLY. Not essential
PARTLY. Not essential
added to the solution?
but adding soap will make
but adding soap will make
it stick longer to foliage
it stick longer to foliage
after rain.
after rain.
Can be stored as ready-
NO, not for more than a few
NO, not for more than a few
made food spray
hours
hours
solution?
Robert Recommends: For large farms, PAN UK and Robert Mensah strongly recommend using the yeast-based product. This waste should be easily available, for free or very low cost, from breweries. It can be stored for some time, so farms can have it ready for turning into the yeast-based food spray as soon as needed. This will also help address the concerns of large farm managers about the labour time and cost for grinding maize for large area application.
The table shows clearly that the yeast-based recipe has more advantages than the maizebased BFP, IF made using brewers’ waste that can be obtained very cheaply and easily. However, availability and easy accessibility is a very important consideration for smallholders. For large farms, labour time and cost of preparing BFP in the volumes needed, whether by mechanised or hand grinding of the maize, may be their most important consideration. The time and labour (and labour cost, if the farmer is not using their own or family member labour) for preparing BFP should not be underestimated, nor the fact that you cannot suddenly make up food spray solution if you have an urgent need - it will take you at least 3 days before you have a solution ready to spray it, or more if you need to obtain the maize too. However, there are ways to reduce labour time and cost of BFP preparation or to organise this differently, (see FAQ below).
48
2.1.4 Food spray preparation costs, compared with insecticides This is an important consideration for any cotton project thinking about using the food spray method. Costs will, of course, vary according to national and local prices for agrochemicals, raw ingredients for the food spray recipes and cost of labour. As an example, Boxes 2A.1 and 2A.2 give estimates for labour time and cost of the maize-based BFP food spray for a
same farm or a neighbouring one.
Box 2A.1. BFP food spray preparation time and cost estimate for smallholders in Ethiopia To make 4kg of dried food spray powder required for one round of food spray application on 1 hectare needs APPROX 6 HOURS LABOUR in: cleaning maize; boiling water for soaking; soaking maize over 24 hours; filtering out, then grinding soaked maize; then soaking again, for 48 hours; then filtering, spreading out and sun drying filtrate till dry.
Input
Item
Unit Cost
Ingredients
8kg maize (to produce 4kg
5 ETB per kg
Total Cost 40
BFP) 2kg sugar
16 ETB per kg
250g household soap
7 ETB per 250g bar
7
79
Subtotal Labour
32
pounding soaked maize
[5 ETB per kg]
40
by hand Subtotal Labour
40
Total food spray preparation costs for BFP for one application on one hectare In July 2015, 1 US$ = 20.5 Ethiopian Birr (ETB)
Source: Ethiopia project field log book (unpublished)
49
119 ETB
Chap.2A
We give a comparison with the 2015 season insecticide application regime, either from the
Preparing and applying the food spray
smallholder and a large farm, respectively, using data from PAN Ethiopia’s 2015 field trials.
applying the food spray
Chap.2A Preparing and
Costs of BFP preparation compared with insecticide purchase for smallholders The smallholder farm in the example above applied just one round of food spray to their trial plot in 2015, with a preparation cost therefore of 119 ETB (approx. US$6) if they needed to pay somebody to grind the maize (or 81 ETB if they used their own labour). Most farmers trained in the Farmer Field School (FFS) project used their own labour, at zero cash outlay cost, although they did highlight that food spray preparation is very time consuming. To give a comparison with insecticide costs, an untrained smallholder in the same village, but using pesticides, in 2015 applied three rounds of malathion 50% emulsifiable concentrate (EC) product in his chemical treatment plots, as part of the same trial. This product cost 160 ETB per litre, applied at 2 litres per ha in each round, totalling his pesticide input cost of 960 ETB (approx.US$47). The BFP input cost, as prepared by the FFS farmer in this example, is therefore around one tenth of the cost of the insecticide application regime used by a neighbouring smallholder growing conventional cotton. Bear in mind, however, that FFS farmers in other villages needed to apply two or three rounds of food spray in the same season, according to their pest and natural enemy balance, so the savings in pest management costs, while still significant, may not be as dramatic as in this example.
Box 2A.2. BFP food spray preparation time and cost estimate for large farms in Ethiopia To make 4kg of dried food spray powder for one hectare: same labour tasks and time required as for smallholder example, using the same traditional hand-pounded mortar method
Input
Item
Unit Cost
Ingredients
8kg maize (to produce
5 ETB per kg
Total Cost 40
4kg BFP) 2kg sugar
16 ETB per kg
250g household soap
7 ETB per 250g bar
Subtotal Labour
32 7
79 pounding soaked maize
[5 ETB per kg]
40
by hand Subtotal Labour
40
Total food spray preparation costs for BFP for one application on one hectare In July 2015, 1 US$ = 20.5 Ethiopian Birr (ETB)
Source: Ethiopia project field log book (unpublished)
50
119 ETB
Costs of BFP preparation compared with insecticide purchase for large farms The large farm in the example applied two rounds of food spray to their trial plots in 2015, with a preparation cost therefore of 238 ETB (approx. US$12). To give a comparison with insecticide costs, the same large farm in 2015 used two applications of endosulfan 25% ultra low volume (ULV) product in the chemical treatment plots, as part of the same trial.
$34). The BFP input cost is therefore around one third of the cost of the typical insecticides used in the same farm’s large scale conventional cotton. Another large farm also participated in the trials, applying three rounds of food spray to their IPM trial plots, compared with four rounds of the same endosulfan insecticide product, applied at very similar dose rates to the first farm. On the second farm, their BFS input cost per hectare was therefore 357 ETB, compared with 1,267 ETB for the endosulfan input cost, again around one third of the cost of the chemical method.
Costs of yeast-based food spray compared with insecticide purchase For large farms or for groups of smallholders, costs will depend on whether brewers’ waste yeast is obtained for free or a small sum, plus any transport needed to collect it. Of course, any transport costs for any insecticides used should also be included in the comparison. However, in most cases, the yeast-based food spray is likely to be considerably cheaper than insecticides.
Cheap and readily available local ingredients used for pest management methods in pesticide-free cotton, Ethiopia. Credit: PAN UK.
51
Chap.2A
3 litres per ha in the second, totalling a pesticide input cost of 696.69 ETB (approx.US
Preparing and applying the food spray
This product cost 126.67 ETB per litre, applied at 2.5 litres per ha in the first round, then at
2.1.5
Question 1: How could you make the maize grinding less applying the food spray
Chap.2A Preparing and
FAQs on food spray preparation laborious?
Answer: There are several options. Good training, education and also forming farmer groups to mass produce the dried powder will all help. Option 1: A mechanised grinding machine. It may be possible for a large farm or a smallholder farmer group to invest in or find donor funding for some kind of handdriven, electrical or diesel-powered grinding equipment. This will add to the initial cost of using food sprays but over time can be worthwhile in the time and labour saved. There will also need to be regular and careful cleaning and maintenance of the equipment. Option 2: Bulk grinding as an income-generating enterprise. A second option is to organise grinding in bulk, as part of a mini-enterprise to produce Benin Food Product at local level, perhaps for a growers’ co-operative or a few neighbouring village groups. Dedicated and trained local people can make BFP powder and sell this to cotton farmers, to make a small profit. The bulk grinding could use mechanised equipment. OBEPAB has successful experience in setting up women’s income generation groups in several villages in the cotton growing zones in Benin to produce cottageindustry neem seed extract, sold at modest cost to local farmer co-operative members. They were able to obtain diesel-powered grinding mills for the women’s groups through donor funding and the women not only grind neem seed and maize for pest control purposes but also provide a local milling service for maize and other cereals. Everybody benefits from these services: The women’s group members benefit from the income generated Cotton farmers benefit from either saving time on preparing their own pest control products (neem seed extract, and maize-based food spray) or buying ready-made products from the mill Other milling service users, often women, benefit from the time saved in preparation of household food and drink products using home-grown or locally grown cereals
52
Question 2: Can you prepare BFP spray solution some days before spraying? How long will the solution stay fresh and active after made up?
based recipe because the yeast or maize ‘dough’ will ferment in the solution, making it hard to pass through the spray equipment nozzle. But you can store the dry ingredients for some weeks: dry, powdered yeast can be stored for over 28 days, as can dry BFP powder.
Question 3: How easy is it to obtain the brewery waste yeast?
Answer: This should be fairly easy, IF the project or farmers’ group contacts a local or national brewery in advance. The brewers’ yeast is a by-product of beer and the brewers usually just throw it away. Fermenting yeast can be a powerful water contaminant so explain that you are helping them get rid of a problem waste product for free! Robert’s experience in Tanzania was that the brewery was keen to give its waste yeast solution to farmers free, maybe because the staff did not know it could be put to valuable use! In the first two years’ trials in Ethiopia, yeast was obtained for free from St George’s Brewery in Addis Ababa by PAN Ethiopia’s Director. Useful Tip: You need to arrange with breweries long before the cotton season commences so you can make sure supplies will be ready when you need them. It’s worth investing time in making personal contacts with different brewery companies and maybe a little negotiation! It’s probably unrealistic for farmers to approach breweries direct, unless there is one locally, and maybe they already supply grain to it.
53
Chap.2A
This won’t work well with either the maize-based or the yeast-
Preparing and applying the food spray
Answer: No.
Question 4: Could you use waste liquid from any existing Answer: Maybe. This could probably work as well as the maize food product, especially for smallholders, who do not need to handle large quantities. You would need to filter out any large particles to avoid nozzle blockage. You would applying the food spray
Chap.2A Preparing and
domestic processing of fermented maize food/ drink?
probably need to experiment with dose rate as it might be more, or less, concentrated than the BFP maize content of the standard food spray. Check that the recipe and processing has not introduced any materials or flavourings that could repel predatory insects. Find out if it contains any sugary or protein content which would provide some level of predator emergency food supply (arrestant). Liquid or semi-solid waste left from other fermented cereals products (e.g. using sorghum, millet, teff, rice) in theory should also work but experiment and compare their effectiveness with BFP. Consider any costs, labour time,
Question 5: Using the Benin Food Spray method, can farmers use the liquid left after the soaked and fermenting maize is filtered out (in Step 7) for grinding and drying?
Answer: This waste liquid will contain some food spray odour and it can be worth applying to cotton rows. You can dissolve the ground food in the liquid and top it up with normal water. After that, filter the solution into the knapsack and spray. But bear in mind that the concentration will not be as high as the final spray product at Step 10, so it’s best used as a ‘top up”. Don’t rely on this weak solution for your first spray of the season.
54
2.2 How you apply the food spray 2.2.1 Equipment Food spray solution can be applied in any standard spray equipment designed for
solid food spray material as carefully as possible from the liquid so that the sprayer nozzle does not get blocked. As the remaining very fine particles of food spray in solution may still be fermenting during spraying it is essential to clean thoroughly the nozzle, tube or lance and spray tank immediately after spraying is finished. Any yeasty or maize ‘dough’ material left inside the sprayer equipment can quickly harden and start clogging up nozzles, filters and openings the next time the sprayer is used, hence the need for careful and timely cleaning after use. Most of the food spray projects in Africa to date have used ordinary knapsack sprayers. In Australia, Envirofeast® and similar food spray products were applied by tractor-mounted boom sprayers using 3 cone nozzles per 100cm spacing, with one nozzle at the top of the crop canopy and two nozzles aimed at both sides of the canopy. Important Note: For conventional farmers using the food spray as part of an IPM programme in which they also apply pesticides, it is essential to use separate spray equipment for the food spray. It is extremely difficult to remove all traces of pesticide residues from most sprayers, even with the industry recommended ‘triple rinse’ technique. Many smallholders using pesticides in developing countries are rather unlikely to be washing their spray equipment out to the standard recommended under Good Agricultural Practice and may well have continual presence of pesticide residues in their kit. If pesticide- contaminated equipment is used to apply the food spray, the solution may well contain traces of pesticide at levels which could harm natural enemies attracted in by the food spray odours. If the contamination is by pungent pesticide products, the smell could mask the food spray odours. Either way, the food spray effectiveness in stimulating extra biological control by predatory insects will be reduced. NEVER APPLY FOOD SPRAY IN EQUIPMENT THAT HAS BEEN USED TO APPLY PESTICIDES (WHETHER INSECTICIDES, FUNGICIDES, HERBICIDES OR OTHERS). Good quality spray equipment is also important. There are many cheap but very poor quality knapsack sprayers available in farming areas in developing countries, often originating from China. These do not spray very well and are not designed to last long. It is a false economy to buy these ’20 dollar’ sprayers. Likewise, investing in a decent household sieve or buying several metres of muslin cloth of fine mesh makes sense for the filtering process when making up the food spray solution. Projects and farmer groups can probably obtain these at reduced price if they buy in bulk from distributors in the larger towns.
55
applying the food spray
product is diluted in water. As mentioned already, it is very important to filter out the
Chap.2A Preparing and
pesticide application where the liquid, granular, powder or EC (emulsifiable concentrate)
2.2.2 Dose rates The standard dose rate tested and confirmed as effective by Robert for both the yeastbased and BFP powder, as used in Benin and Ethiopia, is:
A maximum dose rate of 4kg food spray product can be used if you need beneficial insects to come in very quickly to wait for pests. The 2 kg dose rate is usually fine but you applying the food spray
Chap.2A Preparing and
1-2kg of food spray ‘product’, diluted in 20 litres of water, per hectare
may have to apply another spray in situations when more pests arrive and infestation levels are too high for the beneficial insects to manage. Also if you want to deter egg laying by bollworm female months, then you may have to increase the dose rate as the crop grows and the foliage to be covered expands in area. To this solution, both soap as a sticker and sugar as an arrestant can be added (see quantities in section 2.1.1). As for any synthetic pesticide application, the volume of dilution water will increase, according to crop growth stage and plant height, in order to achieve good coverage as the plants grow. The dose rate of food spray product remains the same, regardless of volume of water, i.e. 2-4kg per hectare. This means that the first food spray, at 4-6 true leaf stage, is more concentrated than later in the season (when sprays are being used as top up of the newly developed leaves) when it is diluted in a larger volume of water. It is important to use this high initial concentration early in the season, when there may be very few natural enemies foraging in the cotton crop because it is not yet an attractive ‘home’ for them. Your aim is to attract them in from surrounding vegetation, which may be many metres away, and you need a strong odour plume to achieve this, by using the high concentration of food product. Later in the season, the larger crop canopy, with pests and other insects arriving and breeding all the time, will automatically be more attractive to predatory insects and it is not so important to have a highly concentrated odour plume. Your subsequent food sprays are more of a ‘top up’ or ‘refresh’ than the initial ‘invitation in’. The high concentration of 4kg per 20 litres water is the minimum concentration for the first, early season application.
APPLICATION METHOD For applying food spray with a standard knapsack sprayer, the best technique is to walk along every other row, i.e. alternate rows, spraying plants to left and right. Wind direction should be taken into account if it is windy. As with applying synthetic pesticides, it’s important to try and get thorough coverage of the plants, including leaf undersides and 56
Application of Benin Food Spray Product to cotton plants. Credit: R Mensah.
inside the crop canopy, where most of the pests live. Make sure that the food spray solution is wetting plants from top to bottom and not just landing on the top of the plants. In early season, when the cotton is first starting to form squares and flowers, you want to ensure maximum protection of the plant’s most valuable fruiting branches, which are the bottom five (i.e. the first produced). The bolls from these branches are usually the highest yielding (see Chap. 3, on good cultural practices) so you aim to
technique.
Robert Recommends: Robert recommends to spray walking backwards with the knapsack sprayer - this slows the operator down and controls his/her speed. You can also see if you’ve properly covered plants and avoid disturbing sprayed plants. PAN Ethiopia have trained farmers to use this backwards spraying technique in their 2015 FFS season- it may require a little practice, with just water in the tank. You can add a coloured dye (e.g. food colouring) into the spray tank to see if you are achieving good coverage of the crop.
Organic cotton farmer sprays food supplement to attract beneficial insects, instead of using insecticide. Benin cotton zone. Credit: OBEPAB.
57
Chap.2A
applied at the correct time, at relatively high concentration and with effective spraying
Preparing and applying the food spray
achieve very effective natural pest control from predator action by getting food spray
Question 1: Do I need to spray the entire field each time I applying the food spray
Chap.2A Preparing and
FAQs apply the food spray? Should I target the spray where there are more pests?
Answer: You don’t use a ‘spot’ treatment approach with the food spray, because you want to attract in predators throughout the field. If you have a particular problem pest that occurs in clusters or ‘hot spots’, you may also want to carry out some more targeted control using a different IPM method (see Chap. 3). However, it is possible to apply banded or alternative row food spray early in the season. Research has shown that banded application increases the predator populations similar to the result from spraying the entire cotton crop but reducing the cost by 33-50%. This banded spray technique could be useful for large farms which have a lot of crop to spray quickly and want to reduce application volumes, time and costs, especially if they are using the maize-based recipe. For smallholders banded or alternate row spraying is not really needed since most seem to manage with preparing the volumes needed for their small plots and the cost is not an issue.
Robert Recommends: Robert’s recommendation for large farms using tractor-mounted boom sprays is to make the first spray as a 33% band at 4-6 true-leaf stage and increase the band width to 50% as the crop grows. Spraying alternate rows is another good option.
58
Question 2: How do you alter the dose rate or volume applied according to crop growth stage?
Answer: As the crop grows the volume of water needs to change to get good
However, if you have high bollworm pressure at certain times and you want to also mask the odour to reduce bollworm egg laying then you need a higher concentration as the crop grows in size. This guidance holds true even if you are adding soap as an insecticidal ingredient or neem to kill larvae you target in the critical pest attack zone (up to 4-5 nodes below the terminal bud of the cotton plant).
Question 3: How do you avoid nozzle blockage problems?
Answer: Carefully filtering the solid matter out of the food spray solution, using a fine sieve or cotton muslin, BEFORE you put it into the spray tank is
good and will minimize blockage. Also, farmers can use nozzles with a larger opening tip, known as full cone tip nozzles.
59
Chap.2A
Your first spray aims to cover the plant’s base leaves at the early season growth stage. The next spray tops up the old leaves and covers the new leaves. If you use the 1 or 2 kg food spray per ha standard dose rate this works to attract predators. If you use the same standard dose rate per hectare throughout the season the initial food spray applications when the cotton plants are smaller will be more concentrated in food spray product per total volume of water applied than the later applications where the water volume is high. This is important as you need concentrated food spray application to first attract the predators into the crop, thereafter any food spray applied is a “top up� spray to maintain the natural enemies in and around the field.
Preparing and applying the food spray
coverage. The change in water volume is the best way to apply the food spray product. The dose rate is can vary from a low concentration of 1kg food spray product per hectare up to a very high rate of 4kg per hectare (for an emergency situation where predator numbers are very low and also when you want to deter bollworm egg laying).
Question 4: Do you need to use and wear Personal Answer: Not really because, unlike synthetic pesticides, you are not dealing with a toxic product designed to kill or harm and therefore requiring the highest applying the food spray
Chap.2A Preparing and
Protective Equipment when applying food sprays?
level of protection for those handling the insecticide. In fact, you can theoretically eat the ingredients and drink the liquid! However, it makes sense to take some basic precautions when preparing and using food sprays. When using yeastbased recipes, avoid breathing fermented yeasts into your lungs, which can give you breathing difficulties. When dealing with the BFP powder at Step 10, you don’t want to get it in your eyes or nose as fine particles of any material can pose a minor hazard to your respiratory tract. The Personal Protective Equipment (PPE) issue is more about setting a good, visual example – it is probably not a good idea for IPM projects with farmers, who may continue to use some synthetic pesticides, to show, for example, photos of people using a knapsack sprayer in a field without any protective clothing! Some of the botanical extracts used as repellents by organic and IPM farmers can be harmful, including irritant to skin, eyes and mouth, and some basic protection should be used when preparing and spraying these. It makes sense for farmers to use some form of gloves, long trousers, long-sleeved shirt, closed shoes or boots, and a head covering when spraying food solution. But it would not be a good idea to wear PPE used for pesticide application, when spraying food spray, in case of any contamination risk which could affect the natural enemies.
60
Sources of information This chapter has been compiled from unpublished data from PAN UK’s Ethiopian cotton IPM training project (see Chap. 4) and using expert inputs provided by Dr Robert Mensah to PAN UK during 2015-2016.
applying the food spray
Chap.2A Preparing and
61
Chapter 2 Using the food spray method in practice 2B. Field monitoring, decision making and habitat management
monitoring, decision making and habitat management
Chap.2B Field
2.3
Understanding about the balance between pests and natural enemies
2.3.1 The rationale behind the Predator to Pest ratio As mentioned in the FAQs in Chapter 1.3, Robert’s research in Australia, Benin and China (Xinjiang Province) and elsewhere has consistently shown that if there is AT LEAST ONE PREDATOR FOR EVERY TWO PESTS in the cotton crop, at any given date, this should deliver enough natural enemy action to prevent the pests from getting out of control within the next few days. Data from three seasons of trials in Ethiopia in small and large farms during 2013-2015 is also reinforcing this conclusion about the required level of balance between natural enemies and their pest prey. This Predator to Pest balance can be written as: o
1 Predator: 2 Pests, or
o
as a ratio of 0.5 Predators per Pest
NOTE: it is not helpful to talk in terms of ratios and fractions with most cotton farmers (or even some extension agents), unless they have done maths at school and enjoyed it! It is better to use the term ‘balance’ and describe it as the farmer needing to make sure that there is at least one predator for every two pests counted in the crop. This ‘healthy balance level’ is what the farmer is aiming for in order to make good use of natural control processes and avoid or reduce the need to apply pesticides. If you have more than one predator per two pests, i.e. the balance is maybe around one to one, or even a higher number of predators to pests, then you should have a very healthy current level of natural biological control.
62
This ratio of 1 Predator: 2 Pests is not a magic number. It is based on scientific research conducted in different locations, different cotton cropping systems and over numerous seasons but it is an approximation and a general ‘rule of thumb’ only – it may not hold true in all cases. Good farmer decision making on pest management will also take account of: ¬ the broader crop health – are the cotton plants looking healthy or not? What about cotton plant diseases, any nutritional deficiencies or stress factors (drought or water logging)? ¬ are the cotton plants retaining their fruits (squares, flowers, bolls) and not dropping them on the ground?
few days? ¬ are there any major pests arriving in large numbers or expected soon? ¬ what might happen to the natural enemies currently feeding in the crop? Are they reproducing? Can you see any larval stages? Learning about the cotton plant’s natural shedding of some buds, flowers and bolls and the crop’s ability to compensate for a certain level of damage is an important part of IPM knowledge. Farmers need to understand the difference between natural, normal shedding and pest-caused damage and learn to identify the symptoms in the field. Achieving good yields involves assessing and ensuring adequate fruit retention at the first positions on the 5 basal nodes (the first fruiting branches produced). As the plant grows you need fruit retention on the 4-5 nodes below the terminal bud. Robert has helped to train smallholders in Benin and Ethiopia on simple techniques for assessing fruit retention, with a ‘rule of thumb’ to aim for delivering adequate pest control function to achieve 60% and above fruit retention after squaring stage on the fruiting branches so that the Predator to Pest balance will work better for the farmer. This involves assessing fruit retention on each sampling date, as well as the counting of insects. It is beyond the scope of this manual to provide guidance on how to do this, as is it only makes sense via practical demonstration in the field and building confidence through experience. Other IPM aspects are discussed in brief in Chapter 3 in the broader context of cotton crop health for effective IPM and how to conduct a Cotton Agroecosystem Analysis.
63
Chap.2B
to favour more pests, or not? How might these conditions change over the next
Field monitoring, decision making and habitat management
¬ are the current growing conditions (e.g. soil moisture level) and weather likely
2.3.2 A constantly changing balance requires frequent monitoring
monitoring, decision making and habitat management
Chap.2B Field
It is very important that farmers and the field agents who work with them and conduct training on the food spray method understand that this balance between natural enemies and pests is constantly changing. Weather, cotton growth stage and growing conditions, actions of the farmer and his/her neighbours and other factors can all affect whether pests start becoming more or less numerous and whether natural enemy levels increase or decrease. This is why farmers need to be vigilant and take time to go into their cotton fields and COUNT INSECTS EVERY THREE TO FIVE DAYS, so they can check whether the balance is healthy or not. If not, and the pests are starting to seriously outnumber the predators, it is time for another food spray and possibly some other IPM actions (see section 2.5 below about decision making based on the counts data from field monitoring).
64
2.4
Field monitoring to check on the Predator to Pest balance
Regular field monitoring, to observe and keep track of the levels of pests and natural enemies present in the crop, is an essential part of using the food spray method. Clearly, to do this the farmer needs to be able to identify the different types of insects and other arthropods (e.g. spiders) commonly found in the cotton plants and learn which are the ‘good’ (beneficial) and ‘bad’ (pest) ones. Farmer training needs are discussed in Chapter 4 and some useful resources listed under Further Reading. The farmer needs to check his or her crop very frequently, about twice per week. This
time goes on. Every time a farmer checks the cotton field, he or she needs to record the number of pest insects and beneficial insects (focusing on common predator groups). Below we give a very simple method of recording, devised for use by smallholders, which does not even require pen and paper. This monitoring method may seem time-consuming and difficult for smallholders to carry out, especially those with little schooling. Of course, they need training and some practice to learn the skill but experiences in Benin, Ethiopia, Tanzania and China prove that trained smallholders can do it well enough to make effective use of the food spray method, checking the current balance between predators and pests and deciding when another food spray may be necessary (or other pest control action). Some may even record the data in their own notebooks, or get their school student children to help them. In Farmer Field School training, the farmers work in small groups of 5-8 people, to learn the monitoring technique, with practice in weekly sessions. By the end of the season, or earlier, most have become competent and confident to do it on their own farms, as well as becoming familiar with the commonly encountered major pests and key natural enemy groups, in their larval and adult stages.
65
Chap.2B
crop in terms of pests, natural enemies and crop damage and how these are changing as
Field monitoring, decision making and habitat management
frequency of monitoring will help the farmer observe and assess what is happening in the
2.4.1 Monitoring pests and beneficial insects: sampling techniques It would be impossible for a farmer to find the time to count all the pests and natural enemies in even a couple of rows in each cotton field. Monitoring therefore involves observing and counting in a small sample of cotton plants in the field. The idea is to take samples in different parts of the field at the same time, rather than just from one area, which might have more or fewer insects than the ‘average’ across the field. If you sample only at one spot, you can seriously under or overestimate your number of pests or natural enemies. Nevertheless, in sampling for pests and beneficial insects, farmers should make sure to sample in at least one area near the edge of the field because cotton pest insects usually start invading and attacking
monitoring, decision making and habitat management
Chap.2B Field
the crops from the edges of field. Farmers should check these areas often as the crop starts to grow. It is good practice to do a quick visual check along the field edges, in addition to the sample areas, especially at times of peak bollworm moth arrivals or other major pests which can suddenly cause outbreaks. Two types of sampling techniques can be used by farmers to make an estimate of the balance between pests and predators in the crop on a particular monitoring date. They are: (1) visual sampling and (2) ‘beat sheet’ or ‘shake plants’ sampling, described below. Whichever technique you are using, you need to observe and count insects from three separate sampling ‘sites’ in the field, on every monitoring day. The sampling ‘site’ used with smallholders and with trained staff is a one metre length of cotton row. The number of plants in this row will depend on the density (spacing distance) you planted at, or thinned seedlings to achieve. It doesn’t matter if your sampling metre row has 5, 10 or 15 plants – the important thing is to be consistent in your particular field, so you are counting insects over more or less the same number of plants each time. To monitor a smallholder-size field on a specific date, the farmer will therefore observe on three, separate one metre sampling rows, spread randomly across the field in order to ‘pick up’ some of the natural variation in pest and natural enemy levels in different parts of the field. For large farms, with fields of 20 hectares or larger, it is best to sub-divide the field into smaller plots for sampling in each.
66
VISUAL SAMPLING TECHNIQUE This involves checking each cotton plant within each one metre ‘sample row’ of cotton plants, as measured with a one metre ruler or a stick cut to the correct 100cm length. You need to observe the whole plant, including squares (flower buds), flowers and bolls, carefully checking the terminals (end buds), leaves, stems, bracts, squares or capsules, flowers and bolls. Then record all the pests and beneficial insects observed in a note book. Annex I gives a simple insect recording sheet template for counts of ‘farmers’ friends’ (beneficials) and ‘farmers’ enemies' (pests).
What you can see: Visual sampling is effective for sampling all insects that are easily visible to the eye. This includes all lepidopteran or caterpillar pests (Helicoverpa species or boll or budworms, rough bollworm, etc.) and also sucking pests (aphids, thrips, brown mirid bug nymphs and adults, green vegetable bugs, cotton stainer bugs) as well as predatory insects, such as lady bird and other predatory beetles, lacewings, spiders, hoverflies, predatory bugs.
Results of pest and beneficials monitoring in a field, showing numbers in each of 3 sample metre rows. Credit: R Mensah.
67
Chap.2B
When to use: Visual sampling is the more effective technique early in the season, when the cotton plants are small, well spaced and can be observed easily and quickly. Also, there will not be large numbers of either pests or natural enemies to count at this stage so it does not take too long to examine and record from each plant in each one metre ‘sampling row’
Field monitoring, decision making and habitat management
A simpler recording method for farmers with low literacy is to represent “pests” using small stones and “beneficials” using maize seeds. Have a small bag of suitable stones and maize seeds ready before you start observing the plants.
BEAT SHEET OR SHAKE PLANT TECHNIQUE
monitoring, decision making and habitat management
Chap.2B Field
In ‘beat sheet’ or ‘shake plant’ sampling, use your metre rule or stick to shake the plants at least 5 times, to dislodge insects in the foliage onto a mat or piece of cloth at least one metre long and 50cm wide, laid on the ground beneath the plants within the metre ‘row’. As most insects are darkish and fairly small, it is easier to spot them if you use a white or light coloured piece of sheet. Count the dislodged insects quickly (before they might ‘escape’) and record the number of pests as stones and beneficials as maize seeds. It is best to do this counting after the 5 shakes, or else some mobile insects may fly away. In shaking the plants, it is essential to dislodge insects from the base, middle and top of the plant. Avoid vigorous shaking that may damage the plant. When to use: In mid to late season, as the cotton crop gets taller and denser (i.e. crops at flowering and boll setting stage), the shake plant method is more effective and quicker than the visual sampling technique. You are unlikely to dislodge all the insects from large plants but you should be getting a consistent and fairly representative sample of what is in each plant and that is good enough for your estimate. What you can see: Shake plant sampling is good for all predators, as well as aphids, mirids, green vegetable bugs, cotton stainer bugs and all sucking and big insects. It may not dislodge pest eggs or very small bollworm larvae hidden away in the square or boll. NOTE: You will NOT see bollworm larvae already feeding inside bolls but you are too late to control these with the predators attracted by food sprays and would need a different IPM control method.
Magnifying lenses help farmers get to know pests and natural enemies, FFS training session, Benin. Credit: OBEPAB.
FFS trainee farmers discussing after cotton crop observation and insect scouting. Credit: PAN Ethiopia.
68
2.4.2
FAQs about sampling and recording Question 1: Does it matter which day of the week you sample or what time of day?
Answer: Time of day is important. It’s best to sample fairly early in the morning, between 07.00-10.00am. This is because natural enemies tend to be
tend to move into shade and hide during the hottest part of the day and do not come out to the top of the foliage to hunt or feed again until it gets cooler in the late afternoon, evening or night. It’s also more comfortable for the person monitoring to do this work before it gets too hot. If you sample during the full heat of the day and strong sunlight, you may miss spotting many of the natural enemies present and underestimate the level of natural enemies present. Day of the week is not important, as long as you are monitoring twice a week, on average, over the full season, from shortly after the date you applied the first food spray at 4-6 true leaf stage until when you start picking. It’s not a disaster if you have to miss a few days for some unavoidable reason.
Question 2: Is it OK to do the monitoring just weekly in each field?
Answer: Not if you want to make the food spray method work properly! Monitoring twice per week is essential if you are testing the method, so you can track trends as they occur and you don’t miss when bollworm eggs or young larvae numbers are increasing above the ‘healthy balance’ (0.5 ratio). However, it’s harder for some smallholder farmers to do this so observing weekly is acceptable BUT if the pest side of the equation starts to rise above ‘double the number of pests to natural enemies’, farmers should really go and check again within 2-3 days. NOTE: It only takes 7 days at 25oC for a bollworm to hatch out from an egg and moult through to 2nd instar stage so you can miss the crucial time to bring in more predators if you don’t monitor every 3-5 days. Once bollworm larvae reach 2nd instar larval stage, they are already starting to penetrate bolls to cause damage, and from 4th instar they become too large for most insect predators to attack (see Chapter 5 for more details).
69
Chap.2B
feeding early morning in exposed parts of the foliage but after 11.00am they will
Field monitoring, decision making and habitat management
more sensitive to high temperature than many pests. Many beneficials will be
Question 3: Should you train farmers to record the different bollworm stages or ignore the larger stages which will not be preyed on by the predatory insects? What about eggs?
Answer: Gaining control of bollworm pests at the lifecycle stages of eggs, very small and small (1st-3rd instar) larvae is essential, as the larvae very soon grow up to a stage where you may lose control. You then end up with very few
monitoring, decision making and habitat management
Chap.2B Field
options able to reach them inside the bolls and control them, even with very toxic and persistent insecticides, such as organochlorines (endosulfan), synthetic pyrethroids, carbamate, organophosphates, etc. Medium and large (4-6th instar) stage larvae are hard to kill with most synthetic insecticides! Farmers therefore really need to be observing bollworm eggs and the very small and small larval stages in their twice weekly monitoring. Farmers should be able to see these very small and small larvae in their checks. This requires training and practice, also for many field staff, to gain experience to carry this out well. Cheap hand lenses are very useful to help with observing bollworm eggs and very small insects. Egg counting is not 100% essential but you will achieve better control of bollworms (at periods when higher egg lays occur and when very small and small larvae are present), to enable you to fine tune the timing of your food spray applications more accurately and effectively and probably deliver higher cotton yields if you do monitor egg numbers. If IPM farmers are keen to avoid use of all synthetic insecticides, they really need to take the time and effort to include bollworm eggs in their sampling. Other pest moth species may lay large, obvious egg masses, which can easily be spotted. Observers need to be able to distinguish bollworm eggs from the eggs of important predators too. Field guides are available. For the larger stage (4-6th instar) bollworm larvae, you do NOT include these in your pest counts (because your predatory insects will not be able to control them). BUT their presence and incidence level is important information for broader decision making beyond food spray application need, so it’s worth recording when and where you see them or the damage they are causing (holes in bolls, deformed flowers, dropping fruits, etc.). If there are many, you will need to think about appropriate, emergency actions.
70
2.5
Simple decision tools for smallholders
In this section we briefly describe how to calculate the predator-to-pest balance, using the data collected in the field monitoring, and then how to use this information for decision making, in the context of cotton smallholders.
beneficial insects and stones to represent the number of pests counted during a field monitoring session. For every beneficial insect found, a maize seed is kept by the person checking, while for every pest found, a stone is kept. Putting these into separate trouser pockets is an easy way to ‘store the data’ while you are sampling. Some people find it easier to have one person observing and counting insects, and another to do the recording. This certainly makes sense when monitoring for trial purposes when the recorder will be taking written notes. During training, farmers will learn to do both observing and counting activities in small groups or with a family member or relative. After the completion of sampling all three, separate metre lengths of cotton per field, all the maize seeds ‘recorded’ are counted up from the three sampling sites and totalled. The same is done for all the stones ‘recorded’ and you now have your current date’s balance of Predators to Pests for that field.
EXAMPLE: you might have observed 5 +3 + 11 natural enemies = 19 total and 7 + 2 + 0 pests = 9 total, making a balance of 19 Predators to 9 Pests.
In this case, there are far more predators than pests and the field has a very healthy balance, well above the level of ‘no more than double the number of pests to predators’. With this healthy balance of natural enemies, there is no need to apply more food spray yet or to take other pest control action as natural biological control should be working well.
71
Chap.2B
In section 2.4.1 above, we described how to use maize seeds to represent the number of
Field monitoring, decision making and habitat management
2.5.1 Calculating the balance of Predators to Pests
2.5.2 Making decisions based on the Predator to Pest balance Now you start the assessment of your current situation of pests and their natural control agents, based on your Predator to Pest balance figure , according to the following decision making process Scenario A: More natural enemies than pests. If the number of maize seeds is higher than the number of stones, the beneficial insects outnumber the pests, and therefore the natural biological control system is functioning well. DECISION: There is no need for food spray treatments, or any additional pest control, at least until you monitor again.
monitoring, decision making and habitat management
Chap.2B Field
Scenario B: Pest numbers are more than double the numbers of natural enemies. However, if the stones outnumber the maize seeds more than two-fold, the pests are winning and you definitely need more biological control! DECISION: The farmer should make a food spray application as soon as possible within the next 2-3 days, to bring more predators into the crop. Scenario C: Equal numbers of pests and natural enemies. This is quite an unusual situation when the number of maize seeds is exactly equal to the number of stones. There is natural biological control going on in the field well within the ‘healthy balance’ level BUT which will increase next – the pests or the predators? If the pest increases first then your balance may become unfavourable in your next count; but if predator numbers increase then the balance should remain favourable! It depends on many factors. DECISION: No need to apply any treatment to the crop but the farmer should re-check the crop within 3 days to see what the trend is (predators up or down?) and then make a final decision. Scenario D: More pests than predators but still within the ‘healthy balance’ level. The field has more than one Predator to every two Pests but the pests might soon be winning. DECISION: You need to also look at fruit damage and loss levels in the crop to help make the best informed decision. The farmer can do this by checking whether:
(i)
the number of fruits (squares and bolls) on a small sample of cotton plants are reducing/falling off (due to pest attack)
(ii) he/she is seeing more holes in any dropped (fallen) fruits If there is a worrying level of fruit loss or damage, then it is time for another food spray. Adding neem extract into your next food spray is one extra IPM option which will also help to reduce pest numbers until natural enemy action can build back up again. It is beyond the scope of this manual to provide detailed guidance on how to assess the cotton crop for fruiting potential or identify whether any loss of fruiting parts is part of natural shedding or due to pest attack. Some guidance can be found in the cotton IPM resources listed under Useful Reading.
72
For large farms and in research trials and with more experienced FFS graduate farmers, a slightly more sophisticated decision making process will be better, as described in Chapter 4. This would include assessment of bollworm eggs and larval size and the decision making would also consider which additional IPM methods could be brought into play, beyond a further food spray application, depending on which methods are available, which work best for certain pests and at certain crop stages. Some additional IPM methods, e.g. biopesticides, can be applied at the same time as a further food spray. You would also reflect on whether any previous food spray applications have been successful, or not, and why. This more sophisticated decision making will be useful in IPM systems. The advice is to try to avoid synthetic insecticides completely or for as long as possible as
Chap.2B
Field monitoring, decision making and habitat management
the season progresses.
FFS participants examine cotton seedlings for pests and natural enemies, Chano Mille village, Ethiopia. Credit: PAN UK.
73
FAQs Question 1: So, how many food sprays might you need to apply in a season? And when might you need to use extra IPM methods?
monitoring, decision making and habitat management
Chap.2B Field
Answer: This depends entirely on what happens in your field – see section 1.3 FAQ 11 in Chapter 1 for the many different factors which can influence the precise balance between pests and natural enemies at any one time. There is no such thing as a ‘typical’ food spray season, because each field and each year is different. Many conventional cotton farmers who rely on insecticides as their dominant method for pest control may make between 6-12 applications per season, or even more if their local situation and poor pesticide practice is triggering pest resurgence and resistance and they have wiped out any useful natural control. The situation since 2013 in much of northern India with major outbreaks of whitefly, especially on B.t. cotton varieties, is a good example, with desperate farmers resorting to cocktails of different insecticides applied more than once a week. There is little hope for these farmers’ cotton growing prospects unless they get support to learn or return to basic IPM principles. Farmers using the food spray method properly, in combination with other good IPM methods, should not reach such a state of ‘crisis’ and may only need to make a handful of food spray applications. Box 2B.1 gives an example from eight FFS villages in Ethiopia, along with comments from the FFS trainers on the possible reasons for the differences in food spray frequency.
74
Box 2B.1. Food spray applications made in FFS demo plots in southern Ethiopia 1st food spray
2nd food spray
Elgo
07 May
15 June
15 July
K/Shelle
06 May
15 June
G/Kanmacha
08 May
03 June
K/Shara
10 May
18 June
15 July
K/Mulato
11 May
22 June
18 July
S/Mella
06 May
16 June
C/Mille
16 May
18 June
10 July
K/Barana
14 May
22 Jun
24 July
3rd food spray
07 August
21 August
Three of the eight FFS sites only needed to make the first food spray, i.e. at the 4-6 true leaf stage. Thereafter, monitoring showed a consistently healthy balance of natural enemies to pests so these sites did not need to make any other food spray applications. The FFS facilitators noted that these sites did not drop below the One Predator to Two Pests ratio and all had surrounding areas good for natural enemy habitat. In two sites, the FFS groups ended up making food spray applications three times over the season. Facilitators reckoned this was because of local weather conditions, the presence of ‘ratoon’ cotton nearby (cotton plants left from the previous season, which serve as a breeding site for bollworm and other pests), plus some other favoured host crops for bollworm were present, e.g. haricot bean. All these factors tend to make pest numbers higher, plus these sites were at some distance to areas of natural vegetation, home to natural enemies. Note: Data from the 2015 season in the Arba Minch area, which was not a particularly high pressure year for African bollworm.
75
Chap.2B
Date planted
Field monitoring, decision making and habitat management
FFS Village
2.6
Making the habitat more favourable for natural enemies
As outlined in Chapter 1, habitat manipulation is one of the components of the food spray method. Intercropping cotton with other companion crops is a tactic that can be used to help manage pests as part of an IPM strategy, suitable for organic farmers too. Planting ‘trap crops’, which are more attractive to key pests at certain times than the cotton plants
monitoring, decision making and habitat management
Chap.2B Field
are, is another very useful tactic for managing habitats.
2.6.1 The aims of managing the field habitat using trap crops Using trap crops and enhancing border vegetation to encourage more natural enemies is relatively simple and inexpensive. What the farmer aims to achieve by making these small adaptations to the field layout and vegetation is to: divert pest pressure away from the main crop, especially egg-laying bollworm moths provide a refuge among taller, denser and earlier sown plants for natural enemies (and other beneficial insects) to live happily, close to the cotton plants attract the nectar-feeding stages of certain natural enemies (adult lacewings, adult hoverflies and many adult parasitic wasps) by sowing or encouraging useful flowering plants in field borders Trap crops can be used to either prevent the target pests from reaching the main cotton crop or concentrate these pests, usually bollworms, in a certain part of the field where the population can be controlled directly (preferably using physical rather than chemical methods). Many work equally well in encouraging more natural enemies to live within and around the cotton field so should also be considered as valuable ‘refuge crops’.
76
2.6.2 Which trap crops to use For generalist plant-eating pests (including some, but not all, bollworm species), which will happily eat a wide range of crops and wild plants, there are many options farmers can choose as their trap crops. Maize, sorghum, pigeon pea and sunflower are probably the most common choices. The ‘secret’ is to choose a crop that will definitely be preferred by the pest at a stage when the farmer really needs to protect his or her cotton plants. It is good to try out different options to see which work best in your particular situation (see Chapter 4).
during the period of squaring and boll formation. The best time to sow the trap crops will depend on the crop and varieties used and local growing conditions. For example, in Ethiopia’s Southern Rift Valley zone, the PAN project recommends that local sorghum varieties need to be sown earlier than the cotton as they are slow growing. If maize is used, sow it at the same time as cotton but not earlier because it matures fast and will start to dry before the cotton starts boll formation, which may divert pests into the cotton plants at the critical stage. The main aim of the trap crop is as a pest management tool but smallholders may often be able to harvest a decent amount from it, usually for household use, so it is not a waste of time or space or cost. For larger farms, the cost of ‘sacrificing’ a little cotton land is often more than compensated by the contribution to improved biological and ecological pest control that the trap crop delivers, resulting in lower expenditure on direct pest control inputs needed and producing higher yields.
Two rows of maize planted as a trap crop and natural enemy habitat in smallholder cotton FFS field, Ethiopia. Credit: PAN UK.
77
Chap.2B
reach their most attractive stage at the right time for ‘pulling’ the pest away from the cotton
Field monitoring, decision making and habitat management
Useful Tip: The key to effective trap cropping is to make sure that the trap crop plants
2.6.3. How to plant trap crops Trap crops can be sown as part of field borders or as bands (strips) within the cotton field. Many smallholder farmers traditionally plant a few food crops (tomato, pepper, etc.) scattered throughout their cotton field. There is nothing wrong with this but it usually works better as a trap crop to plant in a distinct block or band.
monitoring, decision making and habitat management
Chap.2B Field
EXAMPLE: In Benin, research by OBEPAB and the organic farmers found that planting a strip crop of cereal worked well, with two or three rows of sorghum or maize between every 8-10 rows of cotton. Farmers were able to get some usable grain from the cereals.
Intercropping cotton crops with a trap crop of sorghum in IPM cotton, Benin. Credit: R Mensah.
78
Rows of sunflowers planted among cotton as a trap crop for pests and refuge for natural enemies. Credit: OBEPAB.
Chap.2B
Field monitoring, decision making and habitat management
Useful Tip: When using maize as a trap crop or natural enemy refuge border, you need to prevent the maize (which grows quicker and denser than cotton) from shading the cotton plants too much, because many pests are attracted to shadier areas. Planting a close border of maize around a small cotton plot may also end up ‘barricading’ the pests inside the plot, rather than your aim of encouraging them into the maize. Advance planning is important, to make sure you have seed for your chosen crop available at the right time and to work out how much seed you need, suitable planting density and where you want to sow it, in relation to your cotton plantings and field rotations for the new season. Take care with field layouts and plan them in relation to crop plantings on your other fields and on neighbouring farms. If you have planted your cotton late, you risk receiving an invasion of pests from neighbouring maize fields when these are harvested. The pests ‘ejected’ from the maize fields will soon home in on the fresh, green foliage of the late sown cotton and you may get serious pest levels in your mid to late cotton. Timely planting of cotton as well as maize or sorghum is a very important part of IPM tactics to make sure that the trap crops continue to be attractive season long (see Chapter 3).
79
Chapter 3
Integrating food sprays as part of organic or IPM strategies In this chapter we discuss how the food spray method can best be implemented as part of a broader pest and crop management system, whether under an IPM strategy based on ecological principles or in fully organic systems. Although maximising the contribution from natural enemies living in and around the crop is one of the important ecological principles relevant to IPM and organic production, it is not the only one. Progressive farmers will make the best use of available biological and ecological processes and interactions in factors which encourage pests, diseases and weeds. When additional pest control is sprays as part of organic or IPM strategies
Chap.3 Intergrating food
their fields, above and below ground, to grow a healthy cotton crop and to minimise the needed, there is a wide range of methods which can be used, without resorting to spraying HHPs. It is beyond the scope of this Trainers’ Guide to discuss in detail the ecological principles of IPM and organic pest management or to describe the many IPM methods used in cotton systems but you can find references for useful resources under Further Reading. This Chapter looks briefly at: ¬ important IPM principles for cotton and for integration with the food spray method ¬ the importance of good cultural practices and field sanitation ¬ when and how to make use of other IPM methods ¬ suitable IPM methods for bollworm or other key pests, including botanical extracts (semiochemicals), biopesticides, trapping and other techniques
80
3.1
IPM principles and their relevance to using the food spray method
There are many different definitions of Integrated Pest Management and these reflect different opinions about how much crop protection should rely, or not, on pesticide use. PAN UK supports the definition used in the International Code of Conduct on Pesticide Management of the Food & Agriculture Organisation (FAO) and the World Health Organisation:
Integrated Pest Management (IPM) means the careful consideration of all available pest control techniques and subsequent integration of appropriate measures that
human health and the environment. IPM emphasises the growth of a healthy crop with the least possible disruption to agro-ecosystems and encourages natural pest control mechanisms. (FAO/WHO Pesticide Code of Conduct, revised version, 2014)
'Pest' is used as an umbrella term for any problematic living organism affecting the crop. This means not just insect pests, but also cotton diseases, weeds and vertebrate pests (birds, rodents) where these cause problems.
81
Chap.3
interventions to levels that are economically justified and reduce or minimise risks to
Intergrating food sprays as part of organic or IPM strategies
discourage the development of pest populations and keep pesticides and other
3.1.1 Principles of good crop husbandry for effective IPM To manage crops profitably, and without needing to resort to Highly Hazardous Pesticides, involves not only maximising the natural biological control services but also carrying out good husbandry practices that ensure a healthy and resilient crop. Strong, healthy plants are better able to withstand pest and disease attack, as well as adverse growing conditions. This means paying attention to aspects of soil health, water supply and the broader farm environment and choice and sequencing of crops. Effective IPM involves not just management of pests, diseases and weeds but thinking about all the environmental factors and agronomic practices that affect how the crop grows to produce acceptable yields. Box 3.1 provides a list of integrated management practices, from an extension guide for West African smallholder agriculture, which covers most of the
sprays as part of organic or IPM strategies
Chap.3 Intergrating food
aspects of good crop husbandry.
Box 3.1 Good practices in Integrated Pest and Crop Management for smallholders 1. Obtain and plant good planting materials 2. Select fertile soils and suitable planting sites 3. Adopt good nursery practices 4. Adopt appropriate planting distances and patterns 5. Plant at appropriate times so crop growth coincides with low pest and disease incidence 6. Practice crop rotation 7. Adopt good soil management practices 8. Adopt suitable water management practices 9. Do regular weed management 10. Visit fields regularly [to monitor crop growth, pests and natural enemies] 11. Maintain high levels of sanitation in the fields 12. Manage pests and diseases efficiently 13. Enhance the build-up of natural enemies and beneficials 14. Minimise the application of chemical pesticides 15. Adopt good harvesting methods 16. Adopt good, clean storage systems
Source: From the useful Integrated Pest Management Extension series, Guide 1. Principles of IPM: Growing Healthy Crops, compiled by Nigerian IPM expert Prof. Anthony Youdeowei, a Trustee of PAN UK.
82
The Farmer Field School movement interprets the FAO IPM definition and crop husbandry basics in a way that is shorter, more farmer-friendly and relates nicely to the skills that FFS training programmes aim to develop with farmer groups: FFS Principle 1) Grow a healthy crop FFS Principle 2) Conserve natural enemies FFS Principle 3) Observe crops regularly FFS Principle 4) Farmers become experts in crop management
Chap.3
83
Intergrating food sprays as part of organic or IPM strategies
Dr Mensah explaining about a healthy/ productive cotton plant and fruit retention assessment. Credit: PAN Ethiopia.
3.1.2 IPM principles for cotton The IPM principles above hold for all crops and cropping systems, although some aspects will be more important than others in specific crops. In cotton systems, the aim is to manage insect and mite pests, diseases and weeds by integrating a range of IPM tools in order to prevent them from reaching levels which start to hurt the farmer economically. This does not mean eliminating every pest insect or unwanted weed plant or disease-causing organism! Total elimination would not only be impossible but also cost the farmer far more to deliver than the revenue obtained from the cotton harvest. It is essential for cotton farmers to understand that the aim is to manage, not exterminate, pests. Many cotton farmer groups and projects also aim to reduce or phase out synthetic insecticide use completely, whilst maintaining yields and profitability. Growing cotton using sprays as part of organic or IPM strategies
Chap.3 Intergrating food
IPM to achieve higher yields will require the following management activities: • Growing a healthy cotton crop, from site and seed selection to picking • Keeping regular track of trends in insect numbers (field monitoring) • Preserving or conserving beneficial insects for pest management • Using trap crops effectively to ‘share the burden’ of pest problems in cotton crops • Keeping track of cotton fruiting retention and damage ( via plant ‘mapping’ of flowers and boll development, retention and pest attack levels) • Managing crops and weeds that are hosts to pests of cotton For cotton farmers unable to immediately phase out insecticides, good understanding and skills related to pesticide use will be important too: ¬ Selecting less toxic pesticides (‘softer’ pesticides) which cause minimum harm to natural enemies and other beneficial organisms (e.g. pollinators, earthworms, soil bacteria) ¬ Handling and applying pesticides very carefully to reduce exposure of humans, non-target plants and animals, soil and water ¬ Following national or local insecticide resistance management guidelines
84
3.2
The importance of good cultural practices and field sanitation
Growing a healthy crop starts with: selecting a good field or site choosing a suitable crop variety for the location preparing a good seed bed for the crop, whether sown direct or in a nursery bed For cotton, it’s best to avoid fields with too many trees because shading of the cotton plants may lead to reduced crop growth and yields. The trees may also harbour cotton pests, particularly Helicoverpa bollworm species and sucking pests. To encourage good seed germination and seedling growth, land preparation for cotton sowing should make a firm, slightly raised and well-shaped row bed. This helps avoid water logging and good drainage
cotton plant compensating for some early loss of buds and bolls by producing later fruiting branches). As many cotton pests arrive at specific times in the growing season, try not to plant too late beyond the planting window for the location or you may attract pests from earlier sown neighbours’ fields when their cotton becomes less favourable.
Avoid over-enthusiastic applications of nitrogen fertiliser: It is important to get the balance right between too much and too little water and nitrogen. Too much nitrogen, usually from excessive application of cheap, urea-based fertiliser above local recommended levels, can cause rapid cotton growth which can directly provoke increased pest problems in cotton. This is because extra nitrogen causes a flush of juicy, tender, green foliage, which attracts many plant-feeding insects into the crop, especially bollworms, sucking pests like aphids and whitefly. Clean fields thoroughly after harvest: Cotton plants left in the field after picking may not die but can re-sprout some weeks or months later (known as “ratoon” cotton, as cotton is a perennial, not an annual, plant). ‘Ratoon’ cotton provides a hiding place for pests and the perfect breeding site for the next generation of some bollworm species (and boll weevils in the Americas). To prevent the previous season’s cotton fields turning into “bollworm factories”, all bare cotton stalks and any living plants should be removed from the field (for use as fuel, animal fodder or composted), grazed in the field or ploughed back into the soil as soon as practical after the last picking round. Ploughing of the field post-harvest also helps to reduce bollworms pupae in the soil, as they are exposed to heat, sunlight and predators.
85
Chap.3
suits the local climate and soils and has some ability to tolerate insect damage (through the
Intergrating food sprays as part of organic or IPM strategies
reduces the likelihood of diseases at seedling stage. It is best to plant a cotton variety that
Weed regularly: Weeds provide a hiding place for both insect pests and beneficials on cotton farms. However, the presence of too many weeds, especially of plant species favoured by pests such as bollworm or mealybugs, can generate a lot of pest management problems in cotton fields. Therefore, it is essential to clear weeds in cotton fields and on field borders, by hoeing or tractor or ox-driven equipment.
sprays as part of organic or IPM strategies
Chap.3 Intergrating food
3.3
When and how to make use of other IPM methods
It is misleading to give farmers or others the impression that use of the food spray alone will solve all pest management problems. It will not! There are no ‘magic bullets’ in IPM strategies which continue some pesticide use, nor in agroecological or organic systems which do without any synthetic pesticides. The best strategies will combine a range of different methods or tactics: ¬ preventative ones (e.g. good choice of crop variety, good rotations, good field hygiene) ¬ methods that encourage and conserve natural enemies (including the three components of the food spray method) and possibly adding extra biological control ¬ direct intervention methods when the first two tactics do not deliver adequate control of a particular pest or disease in a specific site and season To make these tactics work well, farmer training in ecological principles and IPM methods and regular field monitoring is essential for informed decision making. Each farmer’s situation is unique and the growing conditions and levels of pests and natural enemies will vary every season. It is not possible therefore to make blanket recommendations for which IPM methods cotton farmers should use, even within a particular region of the country. Cotton sector organisations need to support experimentation, learning and experience sharing with farmer groups to help farmers to develop the skills and knowledge to find out what works best for their own farms. Ecologically informed IPM and organic strategies should be robust (based on good science and documented field experiences) but also flexible so that farmers can adapt their ‘basket’ of tools when needed. For smallholders, using the food spray method components as the biological control foundation for their pest management strategy has been shown to work well in the context of organic production in Benin, West Africa (where conventional smallholders apply
86
insecticides mainly on a calendarised basis dictated by the cotton companies). It has been proven in the Ethiopian context too, where smallholders used to apply modest levels of insecticides, but where in recent seasons, low prices for cotton discouraged use of expensive agrochemical inputs and many smallholders have changed to an almost ‘organic by default’ strategy. NOTE: in both the West and East African smallholder projects, farmers are also employing good cultural practices and some other IPM methods, mainly use of neem seed extract. For large farms, good cultural practices and careful field sanitation are equally, if not more, important as for smallholders because they operate over a much wider area. Poor management of cotton plants post-harvest, for example, (in the worst case, plants left abandoned for months after picking) can generate serious bollworm problems in the following season for the farm and neighbouring fields. When implementing the three food spray method components, farm managers will, in most cases, always need to make other
extracts, biopesticides, some form of trapping, or use of softer IPM-compatible newer insecticides, all on a threshold or other decision-making basis per individual field. Options will depend to some extent on which alternative products are available on national markets. For developing an effective IPM strategy that does not rely on HHP use, large farms can start with the food spray method as the foundation for building good natural control and then add further interventions as needed and appropriate, trying out different methods and combinations (see Chapter 5). Reducing reliance on insecticides and avoiding pest resistance problems By using the food spray method, within an integrated and ecologically sensible crop management approach, farmers can reduce their reliance on insecticides and maybe eliminate it in some cropping systems. Preferring non-chemical methods, wherever possible, for managing problem insects is one of the best ways to avoid the dangers of key pests developing resistance to commonly used insecticides. Using the food spray method will help farmers make their cotton production more resilient, more sustainable and more profitable in the medium term than continued reliance on chemical tactics.
87
Chap.3
range of direct control methods is possible, whether use of neem or other botanical
Intergrating food sprays as part of organic or IPM strategies
pest control interventions at some stage, especially if they are aiming for high yields. A
3.4
Suitable direct control methods for bollworm or other key pests
This section gives a brief description of some direct control methods which can be useful, for IPM or organic cotton farmers, to give readers an idea of the range of options. Most of these are developed as commercial products but not all maybe available to farmers in a given country. Some can be produced in either ‘home-made’ or cottage industry level versions, possibly distributed via farmer co-operatives, public sector agencies or very small private enterprises. We cannot make any general remarks on costs or availability as
sprays as part of organic or IPM strategies
Chap.3 Intergrating food
these will vary hugely between countries.
Observing pheromone traps for bollworm in organic cotton field, Benin. Credit: OBEPAB.
88
3.4.1 Botanical extracts and commercial preparations Neem products: Probably the most commonly used botanical method is use of products from the neem tree Azadirachta indica, which grows widely throughout the tropics. Farmers can make their own neem seed extract from collected berries (as is done by the organic farmers in OBEPAB’s programme in Benin, for example) or in some countries, notably India, different nationally manufactured neem products are available in the market. Neem foliage and seeds contain substances that work as insect semiochemicals chemical signals that alter the behaviour of the insect when it detects them by taste or smell. Preparations based on neem have more than one mode of action to manage cotton pests and can act as: repellents; anti-feedants; deterrents to egg laying; as well as direct toxicity effects. Since neem trees can be readily found (or planted, if not) and the home-made
useful role as one of the many possible IPM methods, there are some disadvantages to using neem preparations too often or at too high concentration: o
Neem odour acts as an anti-feedant and it can compete with, or mask, the food spray odour
o
Neem products can sometimes kill pests but they can also kill certain natural enemies or disrupt their reproduction
o
Levels, composition and effectiveness of the azadirachtin active ingredients in neem preparations vary hugely. It’s very hard to get a consistent performance and this is why farmers often report that some seasons they seem to get good results with neem, but not in others
Because neem can negatively affect natural enemies it’s not a good idea to make neem sprays the foundation of an organic or zero-pesticide strategy. Its best use is as a backup tool or when an emergency clean-up is needed IF you cannot get adequate control from the food spray method alone. Data from the Benin trials showed that where neem was included as an ingredient with the food spray, those plots tended to have fewer natural enemies than plots where only the food spray was applied, probably because some of the predators were being repelled or harmed. Neem preparations used as a separate, emergency intervention can be applied at a full rate/dose. If you want to utilize the other, non-lethal modes of action of neem, to deter pests from feeding, egg laying or approaching the crop, preparations are better applied at a reduced rate (1/2 or 1/3 of full dose) to minimize any harmful impact on natural enemies or their foraging behaviour. Neem seed extract can be added into a food spray solution, for this purpose, at reduced dose rate, to help reduce pest infestations or feeding.
89
Chap.3
smallholder use, including in cotton IPM and organic programmes. Whilst neem can play a
Intergrating food sprays as part of organic or IPM strategies
preparations are cheap and easy to make, neem products have been widely promoted for
Other botanical preparations and products: There is an enormous range of plant species with confirmed repellent, antifeedant or toxic properties (see PAN
Robert recommends that if
Germany’s OISAT database and other
bollworm larvae are observed
resources listed in Useful Reading). Beware
on the crops and the Predator
some plants, such as tobacco, which are toxic
to Pest ratio drops below the
to humans too!
favourable level of 0.50, then a
More botanicals are becoming more available as commercial products, with the growth in organic farming and concerns to reduce reliance on harmful pesticides. For example, sprays as part of organic or IPM strategies
Sero X® is a new plant-based, semiochemical
Chap.3 Intergrating food
Robert Recommends:
product developed by Dr Robert Mensah and his team in the ACRI Biopesticides & IPM research group, based on extracts from the
food spray + neem mixture should be used. This should (i) reduce the number of larvae and (ii) attract some predators onto the cotton crop. There is no need to use neem with a food spray if there are only a few bollworm larvae present.
butterfly pea Clitoria terneata, a tropical legume. Robert had noticed its unusually low levels of pest presence when experimenting with butterfly pea as a trap crop. Sero X® has been commercialized since 2015 by Innovate Ag Pty Ltd in Australia as a tool for Australian cotton farmers. Application on cotton crops can deter pest egg laying and larval/nymphal feeding as well as causing direct mortality to larvae and nymphs of cotton pests. The product has no negative effect on beneficial insects.
Poor post-harvest management of cotton on a large farm, leaving plants to resprout as ‘ratoon’ cotton, Ethiopia. Credit: PAN UK.
90
3.4.2 Biopesticides There are numerous biological pesticide products available for control of specific cotton pests, based on specialist bacteria, fungi or viruses which cause fatal disease to certain insects (see Box 3.2 below). B.t biopesticides are based on the Bacillus thuringiensis bacterium, and products suitable for cotton bollworms or leaf-feeding caterpillars are made from strains of the bacterium originally found infecting these caterpillar species. Most B.t. products contain the toxin from the bacterium, and not the living organism, When caterpillars feed on the B.t. toxin it gives them symptoms of “sore throat”, preventing their feeding and resulting in starvation and eventual death of the insect. B.t. products developed for caterpillars should not harm other insect pests or natural enemies. Another group of biopesticides useful for cotton pests is based on the Nuclear Polyhedrosis Virus (NPV), using strains of this virus disease collected from African bollworm or other bollworm species. NPV products are available commercially and, in
The advantages of using living microbial natural enemies, formulated in commercial or cottage industry products, are: It is almost impossible for cotton pests to develop resistance to live biopesticides, because the microbes can evolve to ‘keep up’ with the more genetically tolerant pest individuals in the population Farmers can gain valuable second or third generation biocontrol effects, as the microbes applied in the live biopesticide infect their target pest hosts, kill them and multiply, to release new infective stages into the crop micro-environment.
Box 3.2 Examples of biopesticides used in cotton production In Benin, some organic cotton farmers working with OBEPAB make use of a locally manufactured African bollworm NPV viral biopesticide. In China, many farmers apply B.t. biopesticides, produced by national manufacturers in industrial volumes, at the peak of 2nd generation bollworm egg laying. In India, 3 applications of Helicoverpa NPV biopesticide onto leaves and fruits at 7th and 12th weeks after sowing is one option for direct control of small larval stages of this bollworm.
91
Chap.3
contain the living virus and therefore can be considered as true biological control agents.
Intergrating food sprays as part of organic or IPM strategies
some countries, produced in cottage industry versions too. These NPV products do
However, there are some shortcomings of using biopesticides, which farmers need to be aware of: ¬ Unlike synthetic insecticides, biopesticides contain living microbes. These can be easily harmed by unfavourable conditions, especially high temperature and UV light, and are best applied early in the morning or late afternoon when the sun goes down. ¬ Biopesticides don’t have the same shelf-life as insecticides. They need to be transported and stored carefully, some require cool conditions, and they often need to be used within a period of days (if cottage industry produced) or weeks (if commercial products). ¬ Quality of biopesticide products varies a lot, especially the less
sprays as part of organic or IPM strategies
Chap.3 Intergrating food
sophisticated, locally manufactured or cottage industry versions. In some countries, there are some very poor quality or totally ineffective products on the market. Cotton organisations can train farmers to understand how biopesticides can be used effectively and to support them to access good quality products by sourcing from reputable organisations and running simple quality control and field tests to find out which products work best.
Cotton plants left in the field after harvest become a breeding site for bollworms and other pests, if not removed. Smallholder cotton, Ethiopia. Credit: PAN UK.
92
3.4.3 Using light traps and pheromone traps Light trapping: Many flying insects are readily attracted to light sources at night. This behaviour has been exploited to lure and trap key cotton pests, especially bollworm adults (both males and females) and pheromone traps (only female adults). Putting light bulbs emitting light at low wavelength into cotton fields in the evening and night will attract many adult bollworm moths at their peak flying periods. The trap containing light bulb can be powered by battery, solar power panels, kerosene, other oils or even candles, in suitable containers. Light trapping can catch considerable numbers and prevent these individuals from mating and thereby reduce pest egg laying activity. Traps can also be useful in the IPM principle of regular monitoring, to help farmers pinpoint dates when moths are flying and to inform decision making on direct control interventions. Most ordinary lamps will, unfortunately, trap quite a few other insects, including some
moths and sucking pests than natural enemies. For example, solar-powered Zapper® light models are in use by some Australian growers. With guidance from Robert Mensah, PAN Ethiopia began trying out the Zapper® light in 2015 with two large farms involved in the food spray trials project. However, these lamps are rather delicate and require operators to be trained in using and maintaining the equipment. The lamps will need ‘calibrating’ to see what works best in each large farm’s context. Since 2012, OBEPAB in Benin has been refining the organic pest management strategies, testing additional non-chemical methods which can be useful. These include light trapping, using simple, cheap lamps available locally, employed at peak moth flight periods, to reduce egg laying. Pheromone trapping: The female moths of individual bollworm species release unique communication chemicals, known as sex pheromones, to attract male moths for mating. These pheromones have been studied and developed into commercial lures, specific to each major bollworm species and which therefore do not trap non-target insects. Placed in suitable commercial or home-made traps, most types have a dispenser to release the female’s sex pheromone over several days, attracting the males which are trapped on sticky surfaces. Pheromone traps can seem to catch considerable numbers of pests, but they usually only make a small contribution to the total control actions needed, by reducing the number of males available for mating. They can work well as an additional tool to the food spray method. As with light traps, pheromone traps also serve a useful function as monitoring tools, to identify peak bollworm adult arrival and mating periods. Product quality can vary so the same sourcing and quality control considerations apply as for biopesticides.
93
Chap.3
low wavelength lights, which are much more selective and attract far more bollworm
Intergrating food sprays as part of organic or IPM strategies
beneficial ones. New lamps designed for pest control purposes are now available, using
Training is also needed to make sure farmers know when to put traps out, the suitable density for trap stations, which specific pest they will attract and what to do with the information from trap counts.
Cotton stalks piled at field edge for use as fuel, Ethiopia. Credit: PAN UK.
94
3.4.4 Other methods There are other options for cotton pest control which do not involve harmful broadspectrum pesticides, including products depositing pest-repellent physical coatings on crop foliage, pest suffocating substances (e.g. insecticidal soaps) and the use of petroleum spray oils. Petroleum spray oil (PSOs): These are now one of the major components of IPM in cotton in Australia. Specially formulated PSOs for pest control are known to suppress egg laying of pests such as Helicoverpa bollworms, mites, aphids, mirid bugs, whiteflies and thrips through the process of hiding or masking the attractive volatile chemical signals released by the cotton plant. The oils can also cause insect eggs to abort. However, the most widely known mode of action of PSOs against insect pests is by blocking insect spiracles (breathing holes), causing suffocation. The oils can also penetrate and destroy the insect’s fatty tissues and can directly kill the insects on contact. In addition, the highly volatile oil components can also act as fumigants.
Less toxic and more selective insecticides: Information on the effects of many common pesticide active ingredients on key natural enemy groups is available (see Useful Reading). There are also some newer generation insecticides on the market which are far less toxic to natural enemies and other non-target organisms than the more widely used broad-spectrum products based on organophosphate, carbamate, organochlorine or synthetic pyrethroid chemical ‘families’. Some of these disrupt the insect moulting and metamorphosis processes from egg to larva to pupa, which means they should not harm adult predators or parasitoids. Others are based on chemical active ingredients which are consumed mainly by plant tissue feeding or sap sucking pests and which will not expose as many predatory insects to their toxic effects. NOTE: even so-called ‘softer’ or ‘IPM compatible’ insecticides may cause some harm to certain natural enemies. If these types of insecticide are used as part of an IPM strategy, take care NOT to apply them early in the season when it is important to establish a healthy population of natural enemies in the cotton crop. Early season pest insects very rarely require direct control by any means IF natural enemies can be seen foraging AND the crop is healthy AND managed with good cultural practices. Less toxic synthetic insecticides should only be used as a last resort and limited to emergency interventions in mid to late season, if and when non-chemical methods have failed to keep particular pests from reaching problematic/damaging levels.
95
Sources of Information The International Code of Conduct on Pesticide Management. Food & Agriculture Organisation (FAO) and World Health Organisation (WHO), 2014 version. Available via: http://www.fao.org/ agriculture/crops/thematic-sitemap/theme/pests/code/en/ Integrated Pest Management Extension series, Guide 1. Principles of IPM: Growing Healthy Crops. Anthony Youdeowei (2002) Ministry of Food & Agriculture, Plant Protection & Regulatory Services Directorate, Ghana, and German Development Cooperation. Farmer Field Schools for IPM: refresh your memory. Website of Thailand FFS programme, with resources relevant for other countries. Via: http://ffs.ipm-info.org/http://www.fao.org/farmer-field-
sprays as part of organic or IPM strategies
Chap.3 Intergrating food
schools/en/
96
Useful Reading Information on pesticide effects on natural enemies
Information on the effects of many commonly used insecticides in cotton on five different groups of beneficial insects and spiders is given in the COTTON PEST MANAGEMENT GUIDE 2015–16 for Australian growers. See Table 2 Impact of insecticides at planting or as seed treatments on key beneficial groups in cotton, pp.7-9. Via: www.cottoninfo.net.au Another source of information is the Pesticide Properties Database (sometimes known as FOOTPRINT) of the University of Hertfordshire, UK. Under the Ecotoxicology section for each active ingredient, there is information (where available) on toxicity effects on one or more beneficial arthropods, under the row entries Other arthropod (1) and Other arthropod (2), derived from standard acute toxicity testing. These may refer to the parasitic wasp of aphids Aphidius rhopalosiphi, the predatory mite Typhlodromus pyri or the lacewing Chrysopa carnea
Information on IPM methods Integrated Production and Pest Management Programme in Africa. Farmer Field School approach. Section of FAO website with guidance resources and experiences. Via: http://www.fao.org/ agriculture/ippm/programme/ffs-approach/en/ Field Guide to Non- chemical Pest Management in Cotton Production. On-line Information Service for Agriculture in the Tropics (OISAT). PAN Germany, 2005. Via: http://www.oisat.org/downloads/ field_guide_cotton.pdf Organic Cotton Crop Guide. A manual for practitioners in the tropics. Eyhorn, F et al., 2005. Research Institute for Organic Agriculture, FiBL, Switzerland. Via: https:// www.sustainabilityxchange.info/es/documents/organic-cotton-crop-guide Robert Mensah*, David Leach, Alison Young, Nick Watts & Peter Glennie (2015) Development of Clitoria ternatea as a biopesticide for cotton pest management: assessment of product effect on Helicoverpa spp. and their natural enemies. Entomologia Experimentalis et Applicata 1–15. Robert Mensah, Christopher Moore, Nick Watts, Myrna A. Deseo, Peter Glennie & Angela Pitt (2014). Discovery and development of a new semiochemical biopesticide for cotton pest management: assessment of extract effects on the cotton pest Helicoverpa spp. Entomologia Experimentalis et Applicata 152 1–15.
97
Chap.3
sitem.herts.ac.uk/aeru/ppdb/en/atoz.htm
Intergrating food sprays as part of organic or IPM strategies
and either give an assessment of mortality effect or lethal rate 50 data. Via: http://
Chapter 4
Ethiopian case studies on testing the food spray method and farmer training This chapter aims to give readers more insights into how to try out the food spray method with farmers, including aspects of demonstration and farmer training. By describing in some detail the activities, results and farmer uptake from the three year project in Ethiopia, we hope it gives you a better understanding of how to put the method into practice and the kind of results you may find in terms of yields and net profits. We include data from PAN Ethiopia’s Farmer Field School (FFS) training project with almost 2,000 smallholders and the associated pilot demonstration trials with two large cotton estates, all in the Arba Minch area in the studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Southern Ethiopian Rift Valley. The chapter also describes some weaknesses in the field trial designs and layout, as well as several difficulties encountered in setting up robust trials and assessing the results. We hope that highlighting these shortcomings will help readers avoid making the same mistakes and learn from the experiences.
98
4.1
Activities with smallholders
4.1.1 Smallholder farmer training and demonstration via Farmer Field Schools Under the sustainable cotton project run by PAN Ethiopia and PAN UK during 2013-2015, (funded by UK donor TRAID, see Useful Reading), smallholder farmers were trained on IPM principles and practices using the Farmer Field School (FFS) learning methodology. The season long training was given once a week for three hours per village, covering the usual FFS topics of growing a healthy crop, from land preparation to harvest, good agronomic practices and learning how to identify and monitor pest and beneficial insects. Box 4.1 summarises the FFS curriculum content in the 2015 season. The project was fortunate to benefit from two experienced cotton agronomists who had taken part in an earlier cotton FFS IPM pilot project in the same area, run by FAO in 2006. These two agronomists were already convinced and expert in cotton IPM using reduced or zero pesticides and in FFS methods and were hired by PAN Ethiopia to lead the FFS activities. With other PAN Ethiopia staff, they trained 31 agricultural extension agents from the local Bureau of Agriculture (BoA) and 4 crop protection
available to host and help facilitate new FFS groups in their villages by serving as lead farmers and mentors. The project therefore started with several competent technical staff and farmers with considerable experience and motivation in cotton IPM and interested to explore new options for managing pests without Highly Hazardous Pesticides. The FFS training and demonstration started in three villages in the first season (2013) with 90 farmers participating (30 per village), selected by PAN Ethiopia staff with the help of the zonal and district BoA staff. Financial support from the JJ Charitable Trust (who had helped fund the development of the food spray method in Benin) enabled PAN UK to transfer the Benin experience with food sprays and test the method under Ethiopian conditions. The project also aimed to introduce the food spray method successfully used with organic cotton smallholders in Benin, both with the Ethiopian FFS groups and with any large farms interested. Two experienced field agents from OBEPAB in Benin therefore visited Ethiopia to facilitate a two week training course for 20 field agents (including PAN Ethiopia staff), Plant Health Clinic and farmer participants on how to prepare and apply food spray in cotton fields.
99
Chap.4
subsequent seasons. Several FFS graduate farmers from the 2006 training programme were
Ethiopian case studies on testing the food spray method and farmer training
staff from the Arba Minch Plant Health Clinic to support and expand the FFS work in
Box 4.1. FFS curriculum used in 8 village farmer learning groups, 2015 season
Session
Content
01
Introduction- farmers introduce each other and meet facilitators Decide time and day or weekly meetings, suitable place Facilitators introduce IPM/FFS
02
Land preparation; crop calendar; seed quality
03
Sowing, spacing, plant population Impact of chemicals on biodiversity and humans Health and agroecological solutions
04
Observation, data collection, AESA chart preparation & presentation Drawing conclusions & making recommendations
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Food spray preparation & application Gap filling, replanting 05
Observation, data collection, AESA chart preparation & presentation Drawing conclusions & making recommendations Food spray preparation & application Impact of chemicals on biodiversity and humans Health and agroecological solutions
06
Observation, data collection, AESA chart preparation & presentation Drawing conclusions & making recommendations Thinning Weeds & weeding Irrigation Insect zoo: life cycle of beneficial insects & pests
07
Insect zoo: life cycle of beneficial insects & pests
08
Soils & soil water holding capacity
09
Soils & soil water holding capacity
10
Plants/crop water requirements
11
Plants/crop water requirements
100
13
Sucking & chewing insect pests (aphids, whitefly, jassids, bollworms)
14
Sucking & chewing insect pests
15
Session 14 continues
16
Session 14 continues
17
Watershed management: soil & water conservation, conservation of physical structures, area closure, afforestation, drainage system
18
Session 17 continues
19
Session 17 continues
20
Session 17 continues
21
Compost preparation & application
22
Compost preparation & application
23
Post-harvest methods, lint quality & stainer bug damage
24
Lint quality, picking, storage & yield data Source: Project field logbook (unpublished)
An essential part of the FFS learning process is for farmers to learn how to conduct Agroecosystem Analysis (AESA) in their fields in order to be able to make better informed decisions on when and how to manage insect pests, crop diseases, weeds and to carry out good crop husbandry in nutrient, soil and water management. AESA is based on careful, weekly observation of pests, natural enemies, crop health, symptoms of pest damage or disease, and reflecting on weather and growing conditions in the FFS IPM demo plot and comparing these factors with observation in a nearby plot under farmers’ usual practices. Annex II provides guidance on how Cotton Ecosystem Analysis (CESA) is done in cotton FFS training. The FFS farmers learnt early in the training how to identify major cotton pests and learn about their important natural enemies, thus already providing them with the basic field monitoring skills to be able to count pests and natural enemies for decision making about the food spray method. The FFS programme conducted 20 weekly sessions in each village, with CESA data collected in 19 sessions. The FFS training continued in the second year in the same 3 villages, involving 120 more farmers and repeating the same demonstration trials of the food spray method as in 2013. At the end of 2014, PAN Ethiopia trained over 200 FFS graduates as Lead FFS farmers to help expand the FFS programme to 6 more villages in the third year to reach 2,000 smallholder farmers in 2015. 101
Chap.4
Conclusions & discussion on special topics from sessions 5-11
Ethiopian case studies on testing the food spray method and farmer training
12
4.1.2 Food spray trial treatments and lay-out In 2013 and 2014 seasons, trials with the food spray method were carried out in the host farmer’s FFS learning plot in each of three villages. PAN Ethiopia and their BoA counterparts were keen to compare the yeast-based and maize-based recipes and to look at the effect of including neem seed extract in the food spray mixture. All food spray treatments contained sugar as an arrestant and soap as a sticker. They therefore devised a trial design with six treatments: T1 = Benin Food Spray Product, BFP (maize-based) T2 = BFP + neem seed extract T3 = Ethiopian Food Product, EFP (brewers’ waste yeast) T4 = EFP + neem seed extract T5 = Neem seed extract only
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
T6 = Unsprayed control The trial layout was a standard randomised block design with three replications of each treatment (18 sub-plots in total) on plots of approximately 2,000 metres squared, with each replicate sub-plot measuring 6m x 6.5m, containing 7 rows of cotton, sown at a seed rate of 20kg per ha. Maize borders of 4 rows were planted around the entire trial plot, as part of the habitat manipulation component, one side sown on the same day as the cotton and the other sides when the cotton reached two true leaf stage. Due to some misunderstandings in the initial training by the Beninese field agents, the first food spray treatment was not applied based on crop growth stage (when cotton seedlings reach 4-6 true leaf stage) but based on field monitoring of the Predator to Pest balance. This meant that the first food spray was applied considerably later than recommended. However, the data collected showed that in both seasons natural enemies outnumbered pests early in the season. Table 4.1 summarises food spray applications made at two sites in 2014 in terms of days after planting. Trials at the third FFS site had to be abandoned due to serious drought and, unlike the other two sites, the fields at that site were not able to access seasonal streams for irrigation and the cotton crop was lost. At both successful trial sites, only two food sprays were needed during the entire season, as monitoring showed a healthy balance of natural enemies to pests for most observation dates.
102
Table 4.1. Food spray application frequency and timing at two FFS demonstration sites in 2014 (DAP = days after planting) FFS site
Sowing date
1st food spray
2nd food spray
Shelle Mella
15 Apr
02 Jun (47 DAP) 20 Aug (78 DAP)
-
Chano Mille
07 May
13 Jun (37 DAP) 25 Jul (79 DAP)
-
3rd food spray
Source: Project field logbook (unpublished)
Food spray trial results from the 2013 season had given encouraging first year results with all food spray treatment variations. Details are given in the peer-reviewed paper authored by the PAN Ethiopia team with Robert Mensah (see Amera et al. in press under Sources). The repeat trials in 2014 showed excellent results in terms of yields achieved at two of the three FFS sites (Table 4.2) while the third site suffered major drought and the trials had to be abandoned.
Treatments
Project sites Shella Mella FFS
Chano Mille FFS
T1 Benin Food spray Product (BFP) @ 4 litres per ha
1,600
1,495
T2 BFP + neem seed extract @ 4 litres BFP + 4 litres neem per ha
1,639
1,581
T3 Ethiopian Food spray (EFP) @ 4 litres per ha
1,612
1,519
T4 EFP + neem @ 4 litres BFP + 4 litres neem per ha
1,625
1,543
T5 Neem alone @ 4 litres per ha
1,459
1,425
T6 Unsprayed control
12.26
11.22
Source: adapted from Amera et al. (in press). NOTE: details of standard deviations and statistical analysis of significant differences between treatments are given in the paper.
103
Chap.4
2014 (in kg seed cotton per hectare equivalent)
Ethiopian case studies on testing the food spray method and farmer training
Table 4.2. Treatments and averaged yields from food spray trials at two trial sites in
To put these yield figures in context, untrained smallholders in Arba Minch district were producing between 1,200-1,500kg seed cotton per hectare, with the higher yields in villages with better access to wet season streams or permanent wetlands for irrigation by hand dug channels. The FFS demo sites with the food spray treatment were therefore outperforming the local average yields. Treatment and lay-out adapted in 3rd season trials: In the project expansion stage in 2015, FFS demo plots were conducted at eight villages (six new FFS groups and two existing groups) for farmer participants to compare the food spray method with their current practice (mainly without use of agrochemicals). The original aim was to improve on design and lay-out weaknesses identified in the first two seasons (see 4.3.2 below). To make the method more accessible to local smallholder farmers, only the maize-based food spray recipe was used, as farmers were not able to access brewery yeast. The neem seed extract treatment was excluded, partly to standardise with food spray trials on the large farms and also because it was hard for farmers to source neem seed in their areas. Larger trial plots were used, with treatment plots of 374m2 in order to reduce the level of food spray odour drifting into the control plots from the food spray treatment. Each treatment plot was surrounded by a maize border of 8 rows, to provide refuge for natural studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
enemies and serve as a trap crop, and a path, increasing the separation distance between food sprayed, chemical sprayed and unsprayed plots to 10m. The team aimed to achieve partial replication by comparing pairs of food spray and unsprayed plots hosted in fields of three farmers in each of the 8 villages, as field agents considered it too challenging to set up and monitor fully replicated random block designs on 24 different farms. In the end, even the paired plots proved difficult to organise, due to insufficient human resources and logistical constraints. The food sprayed and unsprayed plots at each FFS site therefore only served for demonstration purposes and could not be analysed formally. In all three seasons, it had proved impossible to set up a comparison of smallholder pesticide practice side by side with the food spray demo plots and under the same agronomic and growing conditions because (i) FFS farmers did not want to use insecticides at all, as this could jeopardise their chances of gaining organic certification (one of the aims of the TRAID project) and (ii) so few smallholders were still using pesticides with low cotton prices since 2012 discouraging use. PAN Ethiopia were able, however, to persuade three smallholders in two villages, who were not part of the FFS group and who were applying insecticides, to allow the field team to monitor pest and natural enemy numbers on a plot in their field and to document their pesticide application in 2014 and 2015 seasons. This data gave a rough comparison, although these untrained farmers were using a different cotton variety (and which might have been a lower quality seed) and not carrying out the same level of good cotton husbandry practices as in the FFS demonstration plots – factors which needed to be borne in mind when comparing yield data.
104
4.1.3 Monitoring of pests and natural enemies Getting to know local pests and their key natural enemies via AESA: The weekly FFS field monitoring sessions helped farmers and field agents become familiar with the range of insect pests occurring in the cotton crop and the most commonly encountered natural enemy groups. With the Lead Field Agents, the FFS groups documented major and minor pests and natural enemies observed at the five cotton crop growth stages, contributing useful local knowledge for cotton pest management (Table 4.3). Ladybird beetles (Coccinellid family), lacewings (Chrysopa family) and hoverflies (Syrphid family) were the most commonly encountered natural enemies, similar to the results from 2013, and they were concluded by PAN Ethiopia and Arba Minch Plant Health Clinic to be the key predators to attract and conserve in IPM or organic cotton in the Arba Minch area. FFS participants were able to recognise eggs, larvae and adult stages of ladybirds and green lacewings by the end of a full season’s training, larval and adult hoverflies and adults of the other natural enemies, as well as some easily observed pollinators, including wild honey bees. They became familiar with the major and minor pests and learnt which ones cause chewing damage, which suck sap or pierce bolls and buds and which cause rasping and sucking damage to foliage. Sucking pests were the main problem pests,
Chap.4
Ethiopian case studies on testing the food spray method and farmer training
followed by bollworms.
105
Table 4.3. Good and bad insects documented in FFS field monitoring in 2014 season Crop stage
Seedling
Good Insects
Bad Insects
Major
Minor
Major
Minor
Ladybird beetles
Spiders
Flea beetles
Bugs
Sawflies
Ants
Jassids
Whiteflies
Praying mantis
Aphids Leafworm
Squaring
Ladybird beetles
Spiders
Flea beetles
Bugs
Lacewings
Ants
Jassids
Stainers
Hoverflies
Praying mantis
Aphids
Thrips
Whiteflies
Cotton semi-looper
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
African bollworm Flowering
Ladybird beetles
Spiders
Jassids
Flea beetles
Lacewings
Ants
Aphids
Bugs
Hoverflies
Sawflies
Whiteflies
Stainers
African bollworm Spiny bollworm Bolling
Ladybird beetles
Spiders
Jassids
Flea beetles
Lacewings
Ants
Aphids
Bugs
Hoverflies
Praying mantis
Whiteflies Stainers Mealybugs
Source: Project field logbook (unpublished)
106
Box 4.2 summarises the pest and natural enemies ‘story’ from the food spray demonstration plot in one new FFS village in the 2015 and compares with the situation in the field of a non-FFS farmer in the same village using insecticides.
Box 4.2 Genta Kanchama village experience with food spray and chemical
In the food sprayed plot, pests outnumbered natural enemies on 6 of 9 observation sessions but often not much above a ratio of 1:1. Just one food spray was applied in the demo plot, on 3rd July (= 64 days after planting). By six days later, natural enemy numbers were double the numbers of (reduced) pests. In unsprayed control plots, pests outnumbered beneficials in 8 of 14 sessions. In the chemical treatment field on a different farm, the team only started records at boll formation. Pests were present in higher numbers than natural enemies. The team noted also that most natural enemies recorded were ants, and only a few were ladybirds, lacewings or hoverflies (the key predators of cotton pests). The insecticide
adults, presumably killed by the insecticide spray applied earlier. There was clearly some immigration of predators from surrounding vegetation because the beat sheet and visual counts showed 45 natural enemies and 42 pests on that date. The team concluded that the farmer would have benefitted from another 100 predators in the plot if he had not sprayed! Observations later that month continued to record numerous dead ladybirds and lacewing larvae, while there were high numbers of aphids and other sucking pests.
107
Chap.4
On the 13 Aug session, the team observed 50 dead ladybird larvae and 51 dead
Ethiopian case studies on testing the food spray method and farmer training
using farmer applied three malathion treatments on 22 Jun, 07 Jul and 27 Jul 2015.
4.1.4 Some summary results from FFS demo plots Raw yield data from the three food spray trial sites in the first year showed varying results and no consistent patterns. The highest yielding treatment was neem seed extract alone at Shella Mella FFS, the maize-based Ethiopian food spray alone at Chano Mille FFS and Ethiopian food spray with neem at Faragossa. At each site, there was not a large difference among any of the five experimental treatments, but the unsprayed plot tended to yield less than others. A crude first economic assessment was made on the trial data at Shelle Mella village in 2013, as this was the only site to make an approximate comparison with smallholder conventional chemical use in a field of an untrained farmer nearby. Table 4.4 gives the yield data, cotton revenues, productions costs for pest management and fertiliser and net margins for food spray only, neem only, unsprayed and insecticide treatments. The neem treatment yielded best, although not significantly different from the two food spray treatments, whilst the insecticide treatment clearly cost the most. In terms of net margin
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
(‘profit’), the neem treatment was a little higher than the food spray treatments.
Table 4.4. Yields, costs and economic returns of food spray, neem, insecticide and unsprayed treatments at Shella Mella village in 2013. Treatment
Seed cotton yield (Kg/ha)
Seed cotton price (ETB/Kg)a
Total revenue from seed cotton (ETB)
Total pest control and fertilizer cost (ETB)
Net margin (ETB)
Benin food product (BFP)
1833.30 ± 88.19 a
10
18,333
85
18,418
Ethiopian food product (EFP)
1866.70 ± 66.67 a
10
18,667
25
18,642
Neem alone
2000.00 ± 57.74 a
10
20,000
640
19,360
1300.00 ± 57.74 c
10
13000
0
13,000
1633.30 ± 66.67 b
10
16333
1395b
14,938
Unsprayed (control) Conventional*
Sig. difference
P < 0.001
Source: Amera et al. (in press) * Plot located on a separate farm 400m from the FFS demo plots. a The price of seed cotton was 10 Ethiopian birr ETB (US$1 = 19 ETB) in 2013. The price was the same for all the types because the food spray cotton was not sold with an organic premium. b Pest control cost for the conventional cotton was inclusive of the costs of fertilizers that were not used in the cotton grown with the use of food spray. The yields of conventional cotton were collected from the smallholders in the study areas.
108
Table 4.5 gives the yield results, pest control costs and net margin (‘profit’) from the 2014 season trials at the two completed FFS demo sites in that season. This time, the yield results for both Shella Mella and Chano Mille sites were similar. Both sites found the lowest yields were with the unsprayed controls. The highest yielding treatment at both sites was the maize-based Benin Food Product with neem. Statistical analysis showed that the treatments which included food spray (whether yeast or maize based recipe) yielded significantly more than the neem seed extract only treatment (representing a common pest management method of organic cotton smallholders). The food spray and neem treatments all yielded significantly better than the unsprayed control plots. Taking pest management costs, yield and net margins into consideration, the most profitable treatment at both sites was, in fact, the Ethiopian Food Product (yeast-based) because it was lower cost than the other three food spray treatments, although it should be noted that the project obtained the brewers’ waste for free for the FFS training purposes. There wasn’t a clear benefit from adding neem seed extract to the food spray because it increased the cost of production without any significant increase in seed cotton yields or net margins.
Chap.4
Ethiopian case studies on testing the food spray method and farmer training
Farmers explain about the food spray and other activities at FFS open day. Credit: PAN Ethiopia.
109
Table 4.5. Yields and net margins of food spray trial treatments at Shella Mella and Chano Mille FFS sites in 2014 season
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Treatment
Shella Mella FFS demo site
Chano Mille FFS demo site
Seed cotton yield (kg/ha)
Net margin in ETB* (Pest control costs)
Seed cotton yield (kg/ha)
Net margin in ETB (Pest control costs)
maize-based Benin food product
1,600.4 ± 82.04a
15,919 ETB (85)
1,495.0 ± 20.70a
14,865 ETB (85)
BFP + neem extract
1,639.3 ± 71.08a
15,668 ETB (725)
1,581.0 ± 74.65a
15,085 ETB (725)
Ethiopia food product
1,615.6 ± 85.32a
16,131 ETB (25)
1,519.3 ± 71.72a
15,168 ETB (25)
EFP + neem extract
1,625.0 ± 83.19a
15,625 ETB (665)
1,543.2 ± 56.31a
14,767 ETB (665)
Neem extract only
1,459.0 ± 103.23b
13,950 ETB (640)
1,425.4 ± 74.65b
13,614 ETB (640)
Unsprayed control
1,226.5 ± 23.68c
12,265 ETB (0)
1,122.3± 103.52c
11,223 ETB (0)
Sig. difference
P < 0.008
P > 0.0013
*
Source: Amera et al. (in press) The price of seed cotton was 10 Ethiopian birr (ETB) US$1 = 19 ETB
110
In the 2015 season, food spray trials were conducted at eight FFS villages but without any formal replication. At two of these sites, a rough comparison was made with conventional chemical smallholders in the same village, to gain an idea of yields, costs and net revenue of the Benin Food Product, unsprayed and insecticide treatments (Table 4.6.) At both sites, the food sprayed plots yielded better than the unsprayed ones, which yielded more than the insecticide-treated ones. The net revenues were highest for the food sprayed treatments, even though the production costs were higher than the unsprayed or insecticide treated plots. Care should be taken in interpreting these results, though, as the conventional smallholders were not part of the FFS, had not received training in good agronomic practices and might have used lower quality seed of a different variety from that planted on the FFS demo plots for the food sprayed and unsprayed treatments. Clearly, good cultural practices play an important part in delivering good yields and profits and the differences in yields and net margins should not be attributed to the food spray use alone.
Site
Treatments
Genta Kanchama
Kolla Mulato
Seed cotton yield (Kg/ha)
Seed cotton price (ETB/Kg)a
Total revenue from seed cotton (ETB)
Total production cost (ETB)
Net revenue (ETB))
Maize-based Benin Food Spray
4,385
15
65,775
9,650
56,126
Conventional/Insecticide
1,497
15
22,460
4,832
17,627
Untreated
3,262
15
48,930
7,324
41,606
Maize-based Benin Food Spray
2,380
15
35,696
5,688
30,007
Conventional/Insecticide
1,497
15
22,460
4,567
17,893
Untreated
1,979
15
29,679
4,757
24, 922
Source: Atalo Belay et al, May 2016. Report for Darwin Initiative on Pesticide Impacts on Biodiversity in Ethiopia & Agroecological Solutions.
111
Chap.4
smallholder plots at Genta Kanchama and Kolla Mulato villages in 2015.
Ethiopian case studies on testing the food spray method and farmer training
Table 4.6. Yields, costs and profits of food spray, unsprayed and insecticide treatment in
4.1.5 Smallholder uptake of food spray method and IPM practices An annual FFS Open Day was held at one participating farmer’s field towards the end of each season, with FFS participants and field agents explaining to invited guests how to prepare the food sprays, showing visitors different natural enemies collected from the field that morning and presenting the results they had obtained with the demo trials and the FFS learning process. These Open Days served as a powerful channel for outreach to farmers and other stakeholders. The technical managers from two large farms invited to attend the 2013 Open Day were enthused by the food spray results in the three FFS sites and, as a result, agreed to offer small plots to serve as IPM trial sites in the following seasons, to see how well the method might work in large scale cotton. Over 200 people attended the 2014 Open Day, with guests from federal government agencies, staff from district and zonal BoA offices, people from large cotton farms and crop protection researchers, guests from district level farmers’ associations and Farmer Training Centres, and untrained farmers from neighbouring villages taking part, as well as FFS graduates.
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Smallholder take up of the food spray method To assess the impact of the IPM training activities on farmers’ practices, PAN Ethiopia compile field records from follower farmers in October 2015, along with interviews to collect testimonials and personal feedback, and conducted an impact survey of a sample of 72 FFS graduates, follower farmers and 26 untrained smallholders in February 2016. Around 12% of untrained smallholders reported using pesticides in 2015 (down from around 25% in the baseline survey conducted in 2013 of similar untrained farmers in the area). Among trained farmers surveyed in 2016, only 3% reported using pesticides and these were farmers who had only attended three or fewer FFS sessions. All farmers surveyed who attended a full season reported stopping use following their training. A majority (63%) of FFS and follower farmers surveyed said they had made use of food sprays and 74% were doing some form of counting pests and natural enemies. Field records from 1,612 follower farmers, however, indicated that uptake of food spray was 25% or lower. PAN Ethiopia field agents suggested that this lower take up rate was probably because (a) follower farmers did not receive a full season’s FFS training and therefore did not fully appreciate the value of using food sprays and (b) many reported that the preparation of the maize-based recipe was very time consuming. In contrast, many FFS graduates clearly found it worthwhile to spend the time in food spray preparation, although in some cases they had benefitted from receiving pre-prepared Benin Food Product powder during training. End of project reflections by the PAN Ethiopia field agents and BoA staff with farmers suggest that most learner FFS participants are keen to use the food spray straight away but they mainly copy the date of application from what is done on the FFS demo plot, rather than monitoring their own fields. More experienced farmers, i.e. those that have
112
gone through a full season of FFS direct training, will generally observe their fields carefully. While only a few trained farmers will do the full beat-sheet scouting as done in the FFS training sessions, most will do some checking of natural enemy presence and numbers, even if they don’t write this down. Over the three years of the project, trained farmers who do use the food spray method reported they have generally needed to apply one or two sprays during a season, sometimes three. Follower farmers do not report as high take up of the method as full FFS graduates, mainly due to perceptions about the time needed for preparation and/or problems encountered with nozzle blockages. However, when the team provided farmers with already prepared product they were much keener to use it! Access to knapsack sprayers (manual pump or pressurised) has not been a constraint to adoption in this part of Ethiopia as some smallholders have their own, others can borrow from friends, or they can rent one fairly cheaply (US$2-3 per day). Anecdotally, trained farmers report that some of their neighbours or relatives are beginning to use the food spray, or show interest. Visitor farmers attending the FFS Field Day or dissemination events organised by FFS Lead Farmers are keen to use the method and have requested training.
had learnt in the IPM training (including use of manure, compost and good cultural practices, as well as use of the food spray method). Figure 4.1 summarises yields and trends for untrained and FFS trained smallholders and follower farmers. Many FFS graduates had been able to plant better quality seed of a Deltapine variety bred for local conditions and distributed at a discount by PAN Ethiopia, while untrained farmers tended to buy seed from local traders, often re-saved for several seasons, and therefore of lower viability and quality than the fresh seed provided via the FFS project. Those farmers with three years’ FFS experience and who had taken part in a full season direct training FFS (compared with ‘follower’ farmers who only received partial and less direct training via Lead FFS Farmers) reported excellent yields, often 50-100% higher than before training, especially in villages with more suitable cotton growing conditions. Box 4.3. provides some testimonial information from members of the two longest standing FFS groups.
113
Chap.4
FFS farmers generally reported a very good increase in yields by taking up practices they
Ethiopian case studies on testing the food spray method and farmer training
Benefits from adopting IPM cotton practices
Fig. 4.1 Trends in average annual yield 2012-2015 reported by trained and untrained farmers in Arba Minch project area. Yield expressed in quintals (100kg) seed cotton per
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
ha
Source: Unpublished project reports. The ‘no training’ data came from a survey of farmers in Arba Minch in February 2016. The ‘PAN trained’ group data comes from field records taken from participating farmers over the course of the project, while the figure for 2012 comes from a baseline survey before FFS training.
114
Box 4.3. Farmer testimonials of the benefits of FFS training on IPM Chano Mille FFS group: Mr Menza Myle is a smallholder farmer involved in IPM training since an earlier FFS cotton project in 2006 run by FAO. He has been an enthusiastic user and promoter of the food spray method since he hosted the village FFS learning site on his farm in 2013. In 2014, he harvested yields of 2,240kg seed cotton per hectare, using IPM practices and the food spray for pest management.
Shelle Mella FFS group: Farmer 1 stopped using pesticides in 2012 and would not go back. â&#x20AC;&#x2DC;We are farmers but we are experts now. We are confident to use and develop these IPM techniques.â&#x20AC;&#x2122; He described going to social gatherings to persuade his friends to join in IPM / organic cotton and said that beekeeping is coming back after some years of decline. Farmer 2 was quite sceptical at first and tried IPM on just a small plot to see how it would work. He is now convinced and has not used pesticides since 2013.
helped them to form a cooperative and to access better seed. They are working to produce their own seed next year. They have also negotiated some land from the local village administration on which they plan to build a store. In the interim, the project has rented storage for them for the next couple of months. This will help them to wait for cotton prices to rise and negotiate a better price.
115
Chap.4
(10-15 birr/kg in 2014, compared to 1.5birr/kg a few years ago). The project has
Ethiopian case studies on testing the food spray method and farmer training
The group reported getting record yields and securing much better prices for their crop
4.2
Activities with large farms
4.2.1 Large farm demonstration and basic training via IPM pilot trials Pilot IPM trials of the food spray method were carried out on one farm (farm A) located 3km from Arba Minch town in 2014, following the same six treatments (replicated three times) and lay-out design as the FFS demo plots but on a larger area of around 4,000m2, with replicate sub-plots of 8m x 13m, each containing 9 rows of cotton. A crude comparison was made with conventional chemical practices on another large farm (farm B) over 23km away. Each farm owns over 1,000ha land, most of which is cultivated, under cotton, maize or other annual crops, as well as some fruit trees. PAN Ethiopia and their BoA counterparts conducted training for farm A’s technical manager and some field staff on pest and natural enemy monitoring, decision making using the Predator to Prey ratio and on how to prepare and apply the two food spray recipes, although the field monitoring was carried out by PAN Ethiopia staff. In 2015, food spray trials were conducted on farms A and B, along the same simplified
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
treatments as in the FFS 2015 demo plots, using only the maize-based recipe and on a larger area, with larger sub-plot sizes (174m2 and 144m2 for each replicate on farms A and B respectively), with maize borders 10m wide. The lay-out this time included a conventional chemical treatment within the trial area, as well as a comparison with each farm’s main cotton fields. Both farms use some form of pest scouting and assessment of economic thresholds to help with spray timing decisions on their main fields. The trial area therefore comprised three treatments, each replicated three times: T1= Food spray using BFP T2= Chemical treatment (insecticide applications, of the same active ingredient, dose rate and application date as the regime on the farm’s main fields) T3 = Unsprayed control The field monitoring was done in a more consistent manner, in order to generate data for standard statistical analysis and which would reveal the direct impacts of pesticide use on target (i.e. pest) and non-target (natural enemy) invertebrates, compared to untreated and food sprayed cotton. Specific objectives for the detailed field monitoring on the large farms were to: • Collect robust data on arthropod diversity in untreated, food sprayed and conventionally grown (pesticide treated) cotton • Evaluate the ecotoxicological impacts of pesticides use on invertebrate diversity • Compare relative abundance of major pests and natural enemies occurring in untreated, food sprayed and conventionally grown cotton • Compare the cotton yield from the food sprayed and conventionally grown cotton
116
Monitoring was done by the PAN Ethiopia Lead Field Agents and the agronomic management decisions of the IPM trial area was also under their direction, while the farm manager decided on the crop and pest management for the main fields. The field agents also collected general cotton agronomic data and on the maize borders, planted as a trap crop and natural enemy refuge and to serve to reduce insecticide drift (Box 4.4.).
Box 4.4. Cotton and maize agronomic parameters observed for each plot Date of planting; Date of emergence; Plant population (density) Date of initial squaring; Date of 50% squaring; No. squares per plant at 5 plant average Date of initial flowering; Date of 50% flowering; No. flowers per plant
Plant height; No. leaves, branches, nodes Date of 1st, 2nd, 3rd pickings Recording of natural enemies, pests, weeds, diseases & others Cultural practices conducted Boll weight, fibre length, strength Yields Data collection on maize: Date of planting; Date of emergence; Plant population Date of tasselling & pollen shedding, silking & maturity Source: Project field logbook (unpublished)
117
Chap.4
Date of initial boll opening; Date of 50% opening
Ethiopian case studies on testing the food spray method and farmer training
Date of initial boll formation; Date of 50% bolls; No. bolls per plant
4.2.2 Monitoring of pests and natural enemies The information presented in this section helps to tell the â&#x20AC;&#x2DC;storyâ&#x20AC;&#x2122; of pest and predator trends in food sprayed and unsprayed treatments in farm A trial plots in the 2014 season, showing examples of the comments written by the PAN Ethiopia field agents conducting the monitoring. Observation sessions were made every 3-4 days over the growing season, totalling 21 observation dates. Data is presented (Table 4.7) from only the maizebased BFP treatment and the unsprayed control, as examples of the numbers observed
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
and crop health status, and on 8 selected observation dates.
Examining cotton foliage for pests and natural enemies as part of IPM training, Benin cotton zone. Credit: OBEPAB.
118
Table 4.7. Insect monitoring observations from IPM trial site on farm A, for
selected dates in 2014.
Crop stage and date
Treatment
Natural enemies counted
Pests counted
Predator to Prey ratio
Comments
Thinning
Food spray
21
7
3:1
Crop looks good but some weeds present.NE numbers higher than pests.
30 May
Unsprayed
29
14
2.07
Initial squaring Food spray
4
3
1.33
06 Jun
Unsprayed
23
8
2.86
30% squaring Food spray
25
16
1.56
23 Jun
Unsprayed
24
21
1.14
Initial boll formation
Food spray
38
43
0.88
Unsprayed
28
29
0.97
Food spray
56
9
6.22
Unsprayed
51
39
1.31
Food spray
50
31
1.61
Unsprayed
91
24
3.79
Food spray
69
65
1.06
Unsprayed
47
44
1.07
Food spray
25
10
2.5
Unsprayed
31
21
1.48
20 Jul 25% boll formation
Fruiting body performance is less, pierced squares are observed. Beneficial insects in case of surrounding pesticide application [on farmâ&#x20AC;&#x2122;s main fields] are not active and less in number than pests so 1st FOOD SPRAY IS NEEDED. Fruiting bodies in better condition plus NE numbers higher than pests after 1syt food spray applied on 14 Jul. Pest numbers reduced considerably. Plant health is good and next irrigation done. NE numbers remain higher than pests so no food spray needed.
01 Aug 50% boll formation 20 Aug
10% boll opening 03 Sep
Plant vegetative growth looks good, weeds have been cleared & latest irrigation done. NE numbers higher than pests so no food spray needed. 44 pollinators recorded in both treatment plots. Rainfall affects boll loss, some rotten bolls observed, & lint grade. NEs still higher than pests but most observed are spiders & ants. Few ladybirds seen because aphids now rare. Fewer pollinators now present due to few flowers plus insecticide spray on same day in neighbouring main field. Source: Project field logbook (unpublished)
119
Chap.4
10% boll formation
Plant growth performance good & beneficial more numerous than pests so that food spray is not necessary.
Ethiopian case studies on testing the food spray method and farmer training
07 Jul
Plant growth & branches in better condition than last week. NEs more numerous than pests but bollworm larvae observed & some pierced squares seen, so follow closely.
4.2.3 Results from large farms The IPM trial plot conducted on farm A in 2014 showed surprisingly high yields compared with averages from this and another large farm’s main fields under conventional insecticide management. The average yield across the six food spray, neem and unsprayed treatment plots in the small IPM research site was 2,050kg seed cotton per hectare, compared with 1,200kg on the main fields of the farm and with 1,650kg average yields from farm B in the same season. This very large difference, of almost double the yield on the IPM trial block averaged across all treatments, could be due to: ¬
differences in agronomic practices
¬
better care was taken on the experimental plots (managed by the PAN Ethiopia team) than the main fields
¬
the large farm was using saved seeds from the 2013 production seasons, while the seeds used in the IPM plots were first generation seeds obtained from the Ethiopian cotton research centre
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
The sites are also located in different places, with possible differences in the agro-ecology. Different management practices could also affect other ecosystem services, for example, the IPM treatments could have encouraged more beneficial soil microorganisms which can contribute to soil health and a healthier crop. Only one food spray was needed on the food spray treatment plots at farm A, far less than the 5 food sprays anticipated in the trial workplan. As in the FFS demo plots in the same season, the reasons could be due to very timely planting, cultural practices well done, experienced field agents monitoring and conducting the trials and favourable weather conditions. These factors did NOT apply to the farm’s main fields, except the weather. Results from the two large farms’ 2015 trials employing the simplified and improved trial design enabled the team to get more detailed and better insights. Table 4.8 gives the treatment dates and frequency of food sprays and insecticide applications made on farms A and B. More food sprays were made than in the IPM trial in 2014, with two sprays on farm A and three on farm B. Table 4.9 describes the details of the insecticide treatments, as decided by the farm management.
120
Table 4.8. Application dates for food sprays and insecticide sprays on IPM trial plots on two large farms in 2015
st
nd
Trial site
1 application
2
Farm A food spray plot (T1)
1st food spray:
2nd food spray:
18 Jul
06 Aug
st
nd
application
Farm A chemical spray plot + main field (T2)
1 insecticide:
2
08 Aug
08 Aug
Farm B food spray plot (T1)
1 food spray:
2
08 Jul
31 Aug
Farm B chemical spray plot + main field (T2)
st
st
nd
nd
rd
3 application
th
4 application
insecticide:
food spray:
1 insecticide:
2
21 Jul
13 Aug
rd
3 food spray: 13 Sep
insecticide:
rd
th
3 insecticide:
4 insecticide:
29 Aug
02 Sep
Source: Project field logbook (unpublished)
Chap.4
Ethiopian case studies on testing the food spray method and farmer training
Table 4.9. Insecticide use by two large farms on their cotton crops production in the 2015 season. Site
Pesticide and formulation
Active ingredient (Insecticide group)
Application frequency/seas on
Applicati on method
Dose litres/ha
a.i. applied in kg/ha per season
Farm A
Endosulfan 25% ULV
Endosulfan 250g/l (Organochlorine)
2
ULVA*
2.5
1.25
Farm B
Ethiosulfan 25%ULV
Endosulfan 250g/l (Organochlorine)
3
ULVA
2.5
2.5
*ULVA: Ultra Low Volume Application, using a battery-operated sprayer
Source: Atalo Belay et al, May 2016. Report for Darwin Initiative on Pesticide Impacts on Biodiversity in Ethiopia & Agroecological Solutions.
121
4.2.4 Economic assessment and impact in large farms An economic assessment was made for the treatments at the two farms, considering yields, production costs and net revenues (Table 4.10). The highest yield and the highest profit was obtained from the food spray treatment at farm A, although there were not major differences between all three treatments. At farm B, the insecticide treated plot yielded most, but with slightly lower costs, the highest profit was from the food sprayed treatment, while the unsprayed plot performed very poorly at this site.
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Table 4.10. Yields, costs and net revenues of cotton grown in food sprayed, unsprayed and insecticide-treated plots at two large farms in 2015.
Farm
Treatments
Farm A
Food spray
2,126
Conventional/Insecticide
Farm B
Seed cotton yield (Kg/ha)
Seed cotton price (ETB/Kg)a
Total revenue from seed cotton (ETB)
Total production cost (ETB)b
Net revenue (ETB)
15
31,896
8,306
23,590
2,016
15
30,173
8,592
21,581
Untreated
1,954
15
29,310
7,805
21,505
Food spray
4,259
15
63,888
12,562
51,326
Conventional/Insecticide
4,329
15
64,931
13,611
51,320
Untreated
1,042
15
15, 626
11,804
3,822
Source: Atalo Belay et al, May 2016. Report for Darwin Initiative on Pesticide Impacts on Biodiversity in Ethiopia & Agroecological Solutions. a The price of seed cotton was 15 Ethiopian Birr (ETB) (U$1=22 ETB) in 2015. b Production cost was inclusive of pest management costs, labour costs and materials
122
The project team and the farm managers were impressed, nevertheless, that the trials showed that the food spray method could work in the context of large scale cotton in Arba Minch to deliver yields as good as or better than the farms’ current conventional pest management and with similar or better net revenue. Average yields from the farms’ main fields were only around 1,100kg seed cotton in farm A and 1,000kg in farm B. The possible reasons for the much higher yields in the IPM trial treatments were: •
all IPM trial plots under same good cultural practices as the ‘IPM’ plot using food spray
•
possibility of some food spray odour reaching non-food sprayed plots in the IPM trial area (although this risk was probably considerably lower than in the small and closely spaced plots in 2014)
•
different agronomic practices and different cotton seed on the farms’ main fields
•
IPM trial sites possibly closer to nearest natural vegetation serving as a refuge or source of natural enemies
Previously the crop protection staff did not take natural enemies into account at all, only conducting a very basic pest scouting. Both large farms reduced pesticide use frequency on their main fields in 2015, compared with the previous season, but it is hard to say whether this was a direct result of their 2013 and 2014 experiences observing food spray plots or other factors. Ten years ago large cotton farms were spraying 8 times per season but overall use has dropped more recently, with lower cotton prices and farm managers mentioned problems in 2015 in obtaining pesticides in bulk from the nearby formulation factory. Both farms have discussed the feasibility of preparing the maize-based food spray for large scale use, because of the labour cost for grinding maize. Some large farms in the area are also using molasses traps for bollworms, promoted by one major cotton standard. These catch both natural enemies and pests, however (probably working on same attractant principle as food spray) and may not be as suitable as other non-chemical IPM methods using light and pheromone traps.
123
Chap.4
keen to use the method on all the farm’s cotton in 2016 and also on vegetable crops.
Ethiopian case studies on testing the food spray method and farmer training
With very good results in yield from food sprayed plots in 2015 farm A’s manager was
4.3
Main findings and lessons learned
4.3.1 Main findings from the Ethiopian trials 2013-2015 Robert Mensah analysed the data from the trials in 2013 and 2014 which had been collected in a form that could be analysed statistically and helped prepare accurate economic assessments, as described above, and discussed the findings with PAN UK and the Ethiopian team. Having visited the trial sites twice, he is enthused about the results and convinced that the method can work for large farms in the Ethiopian context, as well as for smallholders in organic or IPM systems. His technical conclusion is that the results show that applying food spray products can boost the densities of beneficial insects (particularly predatory insects) that are useful for managing pests in cotton fields. The use of the Benin and Ethiopian food products alone increased the abundance of beneficial insects that were able to naturally reduce the
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
number of pests, resulting in higher cotton yields and higher gross returns to smallholders. The main beneficial insects recorded in the food-spray-treated plots were predatory insects, especially species of ladybirds, lacewings and hoverflies, and also spiders (unlikely to be attracted by the food spray). Looking at the detailed scientific results on density of pest and natural enemy groups (see the scientific paper co-authored by Robert, now in press), it seemed that adding neem extract to the food spray reduced the number of predatory insects per metre to levels below those observed with applications of food spray products alone. Despite this probable neem-related reduction in the number of predatory insects, the numbers of predators per metre in the plots treated with food products plus neem were the same as those in the unsprayed plots, and significantly higher than in the plots treated with neem alone. Predatory insects attracted to the food sprayed areas proved sufficient to maintain pest numbers below the economic threshold level, resulting in higher crop yields and better net margins for the farmers, compared with those for conventional insecticide-managed fields. Applying food spray at the early stage of cotton growth (before the build-up of insect pests) definitely helped to increase the number of predatory insects, shifted the predatorto-prey ratio in favour of natural enemies of the pests, resulting in effective biological control of cotton pests. This result is very similar to the conclusions from Robertâ&#x20AC;&#x2122;s earlier work in Australia and the Benin research and subsequent field experience from OBEPAB working with organic smallholders (see papers authored by Mensah, listed under Useful Reading).
124
The Ethiopian trials confirm that food spray products can be affordable and effective lowinput technologies that can be promoted as alternatives to synthetic pesticides in the cotton production context of Arba Minch. For the large farm systems, the food spray method, including habitat management and avoidance of broad-spectrum HHP insecticides, will probably work best in combination with other non-chemical techniques, such as light traps, pheromones and biopesticides that are already in use in other IPM programmes elsewhere. The Ethiopian team is conducting further IPM trials with the large farms in 2016.
Chap.4
Ethiopian case studies on testing the food spray method and farmer training
125
4.3.2. Lessons learned The importance of full and accurate initial training on using the food spray method: It had been intended to bring Robert Mensah to Ethiopia for expert guidance and evaluation of the first season demo trials but this was not possible until the second season. Robert found that the Ethiopian field agents still had considerable uncertainties about the food spray method and its scientific basis and the trials they had set up to try out the food sprays in FFS demo plots in the 2013 and 2014 seasons had several weaknesses: ¬ rather complicated, with 6 different treatments ¬ no chemical control comparison at the same trial sites ¬ small replicate sub-plots too close together to avoid ‘treatment overlap’ from the food spray odour plume reaching some or all of the replicates of neem-only and no spray treatments ¬ first food spray was not applied at the recommended crop stage of 4-6 true
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
leaves, but based on Predator: Prey ratio assessment The same weaknesses applied to the IPM trial site on large farm A in 2014, although the sub-plots were a little larger than in the FFS demo sites. These weaknesses were likely caused by some confusion and interpretation issues with the Beninese trainers, as their guidance had to be translated from French to English and then into Amharic and/or local farmers’ language. The only detailed written guidance on using the food spray method was in French too, based only on the Benin context, hence one of the reasons for compiling this detailed and updated guidance in the form of this trainers’ manual. Also, it would have been much better if the Ethiopian team had liaised with Robert on their trial objectives, design and lay-out in advance of setting up the trial plots and planting the cotton. Potential weaknesses could have been identified and remedied before the trials were started. Adequate hands-on practice is needed for field monitoring and decision making on food spray applications: Unfortunately, the cotton in the FFS demo sites in the first year was planted late and was therefore still at early season stage during the initial food spray training course. It would have been more appropriate for the hands-on practice to have taken place when the crop was flowering and fruiting, i.e. the main pest attack stages. Even with some project staff already familiar with all the cotton pests and some of the natural enemies present in Ethiopian cotton, more practice in identification and monitoring, especially of egg stages would have been good, with feedback and mentoring from somebody expert in identifying these and familiar with the food spray method.
126
The importance of timely and suitable data entry of field monitoring records: This aspect proved very problematic, as the detailed data, while carefully collected and recorded on paper for each treatment and each replicate on every monitoring session, was not then entered into an electronic format which could allow assessment and statistical analysis. Field agents were not confident enough in computer skills to enter the data into spreadsheets and tried to assess it â&#x20AC;&#x2DC;manuallyâ&#x20AC;&#x2122;, using averages across treatments, which is not appropriate. The insect count data then needed to be entered electronically later, extracting the individual replicate figures, and with external help to analyse the data for significant differences and to generate graphical descriptions of the trends over time and between treatments. The process would be improved by setting up customised spreadsheet templates for the exact trial design and lay-out (different plot sizes at different sites) by somebody familiar with spreadsheets and who understands the trial objectives and basic statistical requirements. Excellent cotton production and farmer motivation results were obtained from these three years testing the food spray method in different sites and farm scales, in terms of natural enemy attraction, yields and economic benefits. These were achieved, despite difficulties in trial design, implementation and data analysis. Closer and more frequent
127
Chap.4
future.
Ethiopian case studies on testing the food spray method and farmer training
technical support from food spray experts, especially at planning stages, would help in the
Sources of Information A final report on In-crop pests and natural enemies monitoring in an IPM & conventional cotton plots and an out-crop biodiversity monitoring in agroecosystems and semi-natural forest areas, Arba Minch, Southern Ethiopia. Atalo Belay, Yilma Dellelegn and Tadesse Amera, Pesticide Action Nexus Association, Ethiopia. Report for Darwin Initiative on Pesticide Impacts on Biodiversity in Ethiopia & Agroecological Solutions (project DI 1952), May 2016.
Amera, T, Mensah, RK and Belay, A. (in press) Integrated pest management in a cotton-growing area in the Southern Rift Valley region of Ethiopia: Development and application of a supplementary food spray product to manage pests and beneficial insects. International Journal of
studies on testing the food spray method and farmer training
Chap.4 Ethiopian case
Pest Management
128
Useful Reading A new approach to tackling pesticide dependency and improving livelihoods in Africa. PAN UK project web pages, Oct. 2014. Via: http://www.pan-uk.org/projects/pan-uk-project-sharing-newapproaches-to-tackle-pesticide-dependency-and-improve-livelihoods-in-afr Innovative food spray shows results in non-pesticide cotton production in Ethiopia. PAN UK project web pages, Oct. 2014. Via: http://www.pan-uk.org/projects/pan-uk-project-innovative-foodspray-technology-produces-higher-yields-in-pilot-of-non-pesticide-co Tackling pesticide impacts on biodiversity in the Ethiopian Rift Valley. PAN UK project web pages, Oct. 2014. Via: http://www.pan-uk.org/projects/pan-uk-project-tackling-pesticide-impacts-onbiodiversity-in-the-ethiopian-rift-valley
Mensah, RK. (1996) Suppression of Helicoverpa spp. (Lepidoptera: Noctuidae) Oviposition by Use of the Natural Enemy Food Supplement EnvirofeastÂŽ. Australian Journal of Entomology 35 (4) 323â&#x20AC;&#x201C;329 DOI: 10.1111/j.1440-6055.1996.tb01412.x Mensah, RK. (2002) Development of an integrated pest management programme for cotton. Part
Mensah, RK. (2002) Development of an integrated pest management programme for cotton. Part 2: Integration of a lucerne/cotton interplant system, food supplement sprays with biological and synthetic insecticides. International Journal of Pest Management 48(2) 95-105 DOI:10.1080/09670870110095386 Mensah, RK, Vodouhe, DS, Sanfillippo, D, Assogba, G and Monday, P. (2012) Increasing organic cotton production in Benin West Africa with a supplementary food spray product to manage pests and beneficial insects. International Journal of Pest Management 58 (1) 53-64 DOI: 10.1080/09670874.2011.645905
129
Chap.4
87-94 DOI:10.1080/09670870110095377
Ethiopian case studies on testing the food spray method and farmer training
1: Establishing and utilizing natural enemies. International Journal of Pest Management 48 (2)
Chapter 5 Testing the food spray methods with farmers The food spray method has only been used with relatively small numbers of farmers in a handful of countries to date. For most cotton extension agents and technical staff the method will be totally new so it makes sense to start by trying it out on a small scale to (a) check that the food spray works to attract predator insects in a particular area or cropping system and (b) become familiar with the techniques and observe how the predator and pest balance (ratio) varies over the season and how it can be used to manage pests on cotton crops in the field. In this chapter we firstly provide basic tips on how to demonstrate and try out the food spray method with farmers, as part of Farmer Field School training or similar learning groups. This is followed by more detailed guidance on testing the method scientifically, from thinking about what you want to test, where and how, to carrying out simple trials on small plots, analysing the results and drawing conclusions. Data from well organised and analysed trials can provide useful evidence to persuade farmers, cotton companies and policy makers to support the food spray method. The guidance covers:
research objectives and aspects to consider in trial treatments and lay-out spray method with farmers
Chap.5 Testing the food
¬ Planning and designing experiments with the food spray method- your
¬ Conducting small trials- what data to collect and how to record it
¬ Tips on analysing the data on pests and natural enemies
¬ Evaluating the economic costs and benefits of using the food spray method
¬ Sharing the results with farmers and other cotton stakeholders
¬ Testing the food spray method in other crops
130
5.1
Trying the food spray method out as part of farmer training
In most Farmer Field School training programmes, facilitators help farmers to learn about IPM methods by setting up season-long comparison plots at the FFS site. These plots on the same farm compare the farmer group’s current pest management practices, whether using synthetic pesticides or not, with IPM practices introduced by the programme. Farmers take part in managing the different plots, collecting agronomic and ecological data during weekly Agroecosystem Analysis (see Chap. 4.1.1) and discussing the results. You can take the same season-long comparison plot approach for demonstrating or trying out how food spray application works, along with the simple method for monitoring of pest and natural enemy numbers (as detailed in Chap. 2B). However, you need to bear in mind that the odour from the plot treated with food spray can travel for many metres. If the Farmer Current Practice plot is close by, then the odour might also be attracting predators into that plot too (see section 5.2.3 for a fuller discussion of this issue), turning it into a ‘very diluted food spray effect’ plot. This will make it harder to draw firm conclusions on the differences in pest and predator numbers between the Farmers’ Practice and Food Sprayed plots. To reduce this problem, try to keep a minimum distance of about 8m between the two comparison plots. In a similar way, if current farmers’ practice is to apply insecticides and the Farmers’ Practice plot is too close to the Food Sprayed plot, then drift from the insecticide may kill natural enemies attracted into the Food Sprayed plot, reducing their natural pest control contribution.
the results statistically. However, if several FFS groups at different sites conduct the same comparison of food sprayed plots with the same farmers’ current practices you can get an indication of whether the results show a consistent trend. In addition to pests and predators, you need to record and compare the yields obtained in the food spray plots as well as in the “farmers’ current practice” field. You may want to try out the trap crop and natural enemy refuge component too. You could include this in the set up for the Food Sprayed comparison plot but the effects on insect behaviour of trap crop plants sown in very small plots might not be the same as in a typical 0.25-0.50ha field of smallholder cotton (see 5.2.3. for details). If current smallholder farmers’ practice is to use insecticides, trying out the food spray method should aim to show how attracting in natural enemies can help control pests and deliver decent yields, without use of broad-spectrum insecticides. FFS exercises using petri dish ‘insect zoos’ will help farmers observe and understand what happens when natural enemies come into contact with pesticides (see FFS training guides listed under Useful Reading). If farmers are using zero agrochemicals, then it will be useful to see if applying food spray and adding trap crop rows can improve pest control and yields.
131
Chap.5
Without any replication (repeated plots of the same treatment) it is not possible to analyse
Testing the food spray method with farmers
FFS comparison plots serve for learning and demonstration, rather than formal testing.
5.2 Trial planning: objectives, lay-out and other design considerations
5.2.1 General issues in planning small, agronomic trials with farmers It is beyond the scope of this manual to go into detail on good research planning and design or suitable methods for carrying out agronomic trials with farmers but see Useful Reading for some resources. What this section aims is to highlight some key issues to think about at the planning stage, BEFORE you start to lay out experimental plots. Conducting small research trials is not difficult but it does require careful planning in advance, making sure that everybody involved, especially the farmer(s) volunteering plots and the trained people who will collect the data, understands and agrees: the study objectives (what you want to find out, the questions you want to ask) the different treatments to test and compare what each treatment comprises the plot layouts, including repeats (replications), and labelling
recorded spray method with farmers
Chap.5 Testing the food
how the experimental plots will be managed and the data collected and
If you want to analyse the results statistically (see section 4.3), you MUST involve a friendly statistician at the planning stage! Find somebody who can guide you on the pros and cons of your proposed lay-out and what the stats will be able to tell you, or not, about any differences you observe in the treatments you want to compare. You will need to explain to her/him in detail about how the food spray method works, your research questions and your proposed treatments and plot management, the precise data to be collected and how you plan to record it.
132
5.2.2 Specific issues in relation to testing the food spray method As discussed in Chapters 1 and 2, the food spray method involves three components: (i) applying food sprays to attract and arrest predators, (ii) manipulating the field habitat to make it more favourable for natural enemies, and (iii) avoiding use of broad-spectrum insecticides and other Highly Hazardous Pesticides which may be harmful to beneficial insects. However, it makes the research process much simpler to manage and analyse and to draw firmer conclusions from the results if you break it down into the separate components for detailed technical assessment on what works and how well it works, in terms of attracting natural enemies in and reducing pest levels and/or pest damage. Most cotton support organisations and farmer groups will probably be most interested in testing the food spray component first to see if it can work in their context, then possibly trying out ways to improve the crop habitat using trap crops. We already know that many HHPs will harm many natural enemies so there is no real need to ‘test’ this BUT raising farmers’ awareness of these negative impacts of commonly used pesticides is vitally important! This is best done, however, through separate discovery learning exercises as part of an FFS or similar IPM training programme (see Useful Reading). Testing different food spray recipes: In terms of testing the food spray itself, do you want to try out different recipes or choose one of the recipes in this manual? What are the pros and cons of the proven recipes in your context? Are there other locally available ingredients you might want to test? If you do want to compare different recipes, it is best
predators into the cotton rows. You might also want to see how well they work to arrest predators when prey levels drop temporarily. Remember that part of the assessment with different recipes is also comparing: o
how easy it will be for farmers to access the ingredients
o
how cheap, easy and quick they are to prepare
o
how easily they are applied through knapsack sprayers (nozzle clogging or other problems?) and cover and stick to the foliage
133
Chap.5
and just compare the effect of different recipes on how well they perform in attracting
Testing the food spray method with farmers
to run some very small ‘look-see’ trials where you try to keep all other factors the same
Trying out ways to manipulate the habitat: This research would probably be a second priority for most people after they have tested the food spray attraction performance. However, if you suspect there are very few natural enemies in the crop surroundings, you may want to experiment with adding crops or other plants as refuges for beneficial insects from the start. For example, in very large monoculture cotton fields, or where cotton is grown in very dry or bare soil conditions where there is almost no green vegetation around in the early season. Your research questions could ask: o
Which locally grown food (or other) crops could work as a trap crop for my key pests?
o
When are they most attractive to the pests and how does this compare with cotton?
o
When would be the best time to sow the trap crop and is the trap crop economical to use?
o
Which trap crops will quickly grow to provide a dense foliage habitat that works as a refuge for natural enemies, especially when the cotton plants are small?
o
What field arrangement(s) of trap crops will work best for local farmers (e.g. 2 or 4 rows between every 8 rows of cotton)?
Good entomologists or IPM practitioners in your country may already have useful worth contacting any organic cotton grower organisations to see what options they are spray method with farmers
Chap.5 Testing the food
experience to share on trap cropping and providing refuge for natural enemies. It is well using for habitat improvement and how well these perform. Useful Tip: donâ&#x20AC;&#x2122;t be tempted to try too many different treatments at once in your preliminary food spray or trap crop trials. This makes management trickier, data collection more time consuming, analysis much more difficult and if you end up with lots of very small plots for the replicates (repetitions) of each treatment very close together, you will find it hard to distinguish clear differences between the treatments (see below). Stick to two or three treatments maximum, along with some form of â&#x20AC;&#x2DC;controlâ&#x20AC;&#x2122; treatment (i.e. unsprayed, or no trap crop present) as your baseline comparison. Agree on which recipes or trap crop arrangements you think may be best and try those out first. You can always do a second set of trials, with different options, if none of the first trial treatments deliver good results. In these small scale trials exploring the ecological performance of the food spray or trap crop in terms of pest management, you need to aim to keep all other growing condition factors as similar as possible in the comparison plots, so that any differences in natural enemy and pest numbers and pest damage levels are more likely to be due to the effect you are testing. For example, make sure the cotton is the same variety, sown at the same time, under the same fertilisation practice, etc. It is also important to ensure that the
134
different treatment plots are on similar soil conditions. If the replicates of your food spray plots are in a waterlogged part of a field, for example, while the unsprayed ones are all in better drained parts, this could affect your results and confuse your interpretation of what the results mean.
Assessing the food spray method as part of an integrated system: Most technical support providers (e.g. local extension services, NGOs, cotton research institutes, technical staff in farmer co-operatives) will also want to find out how well the food spray method (comprising its three components) performs, as part of an IPM strategy, in comparison with farmers’ current practice. This current practice might be high intensity insecticide use on large or small farms, with applications on a calendar basis, or using some form of pest scouting and spraying when economic thresholds are exceeded. It might be organic ‘by default’ production, with smallholders using little or no agrochemicals if they are unable to access or afford them or when current cotton prices and markets make it hard to recoup the expenditure on external inputs. To assess the whole food spray method as part of an integrated strategy, it is best to conduct slightly larger scale comparison trials than the detailed technical ones for the food spray or trap crop options. It makes sense to do this in a second season, after you have studied whether the food spray will work in your context. For these system economic comparison trials, you will certainly want to compare performance of the food spray
Which pest management strategy has the lowest production costs (inputs, services and labour)?
o
Which strategy results in the lowest pest infestation and the highest level of natural enemies?
o
Which strategy is easiest and/or least time consuming for farmers?
o
Which strategy delivers the highest yields?
o
Which strategy delivers the best cotton lint quality?
o
Which strategy results in the highest net income in farmers’ pockets (gross revenue from cotton sales minus production costs)?
o
Which strategy is more likely to be sustainable and environmentally sound?
135
Chap.5
o
Testing the food spray method with farmers
method with the current practice, in terms of:
Clearly, with this kind of cropping systems comparison trial, the agronomic practices, and possibly growing conditions, will be different between the ‘food spray system’ and the ‘current practices system’. What you want to assess is the economics of the different systems, including the differences in agronomic practices (see 4.4). If you already have decent data on pest and natural enemy balance and trends from small scale trials with the food spray alone, you do not need to repeat the effort and time in detailed sampling in these systems. Instead, you can use final yield as a proxy measure of pest control performance but do reflect on the many different factors in the different system agronomic practices that may contribute to any significant differences you document in yields, when you reach the interpretation and conclusion stages. Assessing fruit retention (% retention of squares and bolls in fruiting positions) at least once a week is also a good way to track productivity and pest damage levels as the season progresses.
spray method with farmers
Chap.5 Testing the food
Farmers explaining about the food spray and other FFS processes to visitors at FFS open day. Credit: PAN Ethiopia.
136
5.2.3 Considerations about food spray testing and experimental lay-out How effective natural enemies are in suppressing pests will vary according to which type of natural enemies are involved and the techniques used to enhance them. For example, the IPM components developed by Robert Mensah in the Australian large-scale cotton context (see Chapter 1) may not be the best mix for other situations and each context needs its own biological and ecological characteristics to be assessed. This is why PAN UK invited Robert to help our partners in Benin and Ethiopia trial the food spray method in their particular contexts. This does not mean spending years doing detailed ecological research but it is essential to find out: ¬ which natural enemies are effective controllers of major and minor pests in cotton under local growing conditions and production practices ¬ which natural enemies are attracted into the crop when using food sprays and at what level (density of natural enemies per plot) ¬ whether the natural enemies attracted are able to deliver enough of a pest control contribution to be useful for the farmer (in terms of pest damage reduction, fruit retention or, more practically, yield data) Some of this information may already be available via entomologists or biocontrol experts in national research organisations, so consult them and, if possible, involve them in advising or helping with your research. It is worth carefully designing small-scale trials to
(because natural factors related to location hugely affect growing conditions and insect numbers). Here we provide important guidance on lay-out considerations when testing the performance of the food spray. Avoiding cross-contamination between treatments: It is obvious when comparing an insecticide-treated plot with an unsprayed or an IPM plot, that there is a risk of insecticide drift cross-contaminating the other treatment plots if they are too close. This would make the results confusing and this is why in standard trials using pesticides, most researchers will ensure there is at least a 5-10 metre ‘buffer zone’ separating any insecticide-sprayed plots from those without insecticides. Some may plant a few rows of maize or similar tall plant as an additional, physical barrier to reduce the risk of the non-insecticide plots becoming contaminated. The same cross-contamination risk holds for use of the food spray because the food spray solution releases a powerful odour plume, which can disperse for many metres and be detected by predator insects some distance away. Robert’s recommendation therefore is to separate food sprayed experimental plots several hundred metres away from unsprayed and insecticide comparison plots, to ensure that the odour plume does not interfere with the other treatments and attract more than
137
Chap.5
natural enemy population levels will vary each season) and in at least three sites
Testing the food spray method with farmers
answer these questions, probably repeated in two or three seasons (because pest and
the ‘background’ level of natural enemies into the non-food spray plots. If you have food spray treated plots close to unsprayed, then the latter may end up as ‘dilute food spray’ plots by mistake! In practice this can be difficult, if not impossible, in smallholder fields. In larger farms it is possible but most statisticians will point out that growing conditions in widely separated treatment plots are likely to be different and therefore contribute considerable variability into the analysis, making it harder to see where there are clear, statistically significant differences between treatments. They prefer to have treatment plots fairly close together (along the lines of standard insecticide versus unsprayed plot lay-outs) to make the background conditions as similar as possible and to spread the replicates of each treatment across the range of soil or other variation factors. They will advise the usual random block design (e.g. 3 treatments with 3 replications each = 9 experimental plots, randomly allocated for position in the experimental field), with sufficient repetitions of each treatment to generate robust data which can be analysed by standard statistical methods. Food spray experimenters are therefore faced with a dilemma: how far to separate the treatment plots and their replicates to avoid the food spray odour plume ‘drifting’ into the non-food spray plots while also satisfying the statisticians’ demands for random block layout and minimising background variation? There are no easy answers and, as in much field-based research, you will need to make some compromises. Compromise option a: Standard randomised block layout but ensuring a minimum insecticide trials, with a random block design but trying to maximise the separation spray method with farmers
Chap.5 Testing the food
separation between each plot. The simplest is to lay out the trials similar to standard distance between each replicate plot, so that they are at least 8-10 metres apart. You will not eliminate the risk of the food spray odour reaching replicates of some of the ‘control’ treatments but you can reduce it. More importantly, you are aware of the risk and should consider it carefully when you analyse the data and discuss the results. Compromise option b: Keep the food sprayed plots well distanced from the controls. This is the option taken by Robert in his trials work in Benin, with the chemical treatment comparison plots in a different farm’s field 60 metres away, to avoid any insecticide or food spray odour plume drift. You virtually eliminate the risk of food spray odour affecting the other treatment plots but you then face problems with standard statistical analysis. There are ways around this and Robert has successfully published several papers in international peer-reviewed journals, proving that his trial layout and analysis methods are accepted by other scientists. But it is best to consult with a good statistician, or with Robert himself, on how to do the analysis and interpret the results.
138
Compromise option c: Use very large plots and sample only in the centres. If you have lots of land available, you could set up huge sized plots so that you sample only in the centre of each replicate plot, to avoid the treatment ‘overlap’ problem. To do this you would need each replicate plot for each treatment to contain approximately 15 rows x 25 rows of cotton. Impossible in smallholder cotton and a challenge in most larger farms too. Whichever option you take, conducting the same trial in different places and/or seasons will help you assess if the differences (if any) in pest and natural enemy patterns you observe between treatments show consistent trends and give you more confidence in drawing conclusions from a larger data set, collected under a wider range of conditions. Handling the trap crop lay-out arrangements This is difficult to do in small trials with small plot sizes, when your main focus is assessing the food spray effects, because the trap/refuge plants or rows won’t function in the same way as in the complete field in practical implementation. If you ‘box in’ each replicate plot with a maize border, for example, in small plots the maize may start shading out some of the cotton plants, attracting in more pests than usual, and/or affecting yield. A tight border of maize or other cereals around a small square of cotton plants can result in ‘trapping’ the pests inside your treatment plot, when under full field conditions, they would be freer to choose whether to lay eggs on, or move into, rows of maize or rows of cotton. While maize borders serve some useful function in reducing insecticide drift, they don’t work as a barrier to the food spray odour plume.
do want to include trap crops when you are comparing the whole food spray system with farmers’ current practices in larger scale field trials, because they are a fundamental component of the food spray method.
139
Chap.5
small plot trials where you want to explore the food spray attraction effect. You probably
Testing the food spray method with farmers
Overall, it is simpler and best not to try and include any trap/refuge crop arrangements in
5.2.4 Tips for trials in smallholder and large farms Smallholder trials: You may want to conduct these as part of FFS or other IPM training. Think carefully about what you want to find out and what you want to demonstrate to farmers. It may work better to conduct different experiments or learning exercises for these two different aims. If you are unsure about what might work, it is better to do a simple, preliminary trial, under good scientific management, in which farmers can be involved to some extent, through visits and group discussion on the aims, methods and results, but where the treatments and plots are managed by the training or research organisation. Explain that these are experiments and you don’t know what the results will be. You can do much smaller, non-replicated demonstration exercises applying the food spray on a small plot, to show to farmers that the food spray can attract in natural enemies and training them how to do the smallholder counting and assessment of the balance between Predators and Pests. You would not be able to analyse the results formally. If you do a full food spray trial in a smallholder field, make sure that the farmer fully understands what the treatments are and the need to keep with these throughout the season. Ask her or his permission not only to offer part of their field for the experiment but to agree not to interfere in or suddenly change the crop agronomic management. It is usually best if the support organisation staff manage the lay-out, treatments and data some way, with some appropriate training, so they feel some degree of ownership in the experiment. spray method with farmers
Chap.5 Testing the food
collection though it is possible to involve the farmer (and his or her family members too) in
Don’t confuse the experimental design and analysis by making it too complicated, with too many treatments. Keep a minimum separation distance between plots, preferably at least 8-10 metres to avoid the food spray odour overlap problem. Make sure you have some degree of replication, otherwise you cannot draw any useful conclusions. Keep the farmer training group informed of the trial progress, through visits and/or showing photos of what is happening. Large farm trials: Many of the same methodological considerations will apply to trials on plots in large farms. Be careful about spray drift from conventionally managed fields nearby, especially if using tractor-mounted or aerial equipment, and take this into account when looking at the data. Again, it is best to manage the trial lay-out, treatments and data collection yourself, but involve the farm manager and relevant field staff as much as feasible. By assisting and observing the trial operations, playing some role in the data collection and taking active part in discussing the results and conclusions, farm staff are learning ‘on the job’ and gaining skills and motivation. If the farm hires a technical manager, you may want to present the results personally to the farm owner too and make sure he or she fully understands what has been done and your recommendations based on the results.
140
For developing an effective IPM strategy that does not rely on Highly Hazardous Pesticide (HHP) use, large farms can start with trialling the food spray method as the foundation for building good natural control but make it clear that they will need to add further interventions as needed and appropriate, once they try the method at full field scale. They can perhaps start in the first season with some simple small or medium size, replicated treatment plots comparing Predator to Pest ratios, fruit retention (square and boll counts) and pest damage levels in the food sprayed treatment with their conventional, chemical current practice (whether this is by mainly calendar-based applications or based on pest scouting to see when any relevant economic thresholds for key pests are reached ) to see what difference it makes in natural enemy and pest presence and biological control contribution. The yeast-based recipe will be the easiest and cheapest version of the food spray for them to use. Finding out what is required for the habitat manipulation component could be the next step, in a second or third season. There may be adequate natural enemy abundance in the agroecosystems around the large farms as long as they are not being sprayed too often with harmful insecticides or on too wide an area and there is suitable natural vegetation or unsprayed crops fairly close by to serve as refuge. But these are assumptions you will need to check.
Chap.5
Testing the food spray method with farmers
Demonstration of techniques of preparing Benin Food Spray product. Credit: R Mensah.
141
5.3
Observations, data collection and entry
For trials testing the food spray or exploring trap/refuge crop arrangements, you will be collecting regular data on the numbers of pests and natural enemies in each replicate plot in the different treatments and calculating the Predator to Pest ratio. You will probably also want to assess the crop health, levels of certain pest damage, fruit retention and measure final yield. For the large scale comparisons of the food spray ‘system’ with farmers’ current practices, you will be collecting economic data too, including input costs, labour time required and its costs, yield and revenue and calculating net income (profit). The need for careful and skilled observation and data collection: Whether these trials are in smallholder fields as part of an IPM training programme with farmer groups or on individual, large farms it is essential to collect data carefully and consistently and to record it in a way that it can be easily stored, shared and analysed. Without robust data collection so that results can be assessed clearly and properly, testing could be a waste of
5.3.1 Field observations and insect sampling spray method with farmers
Chap.5 Testing the food
time and effort.
You will need to have a small team of people trained or already skilled in identifying the major and minor pests and in commonly found natural enemy groups. Although it is a nice idea to involve farmers and others in sampling, for robust, scientifically valid assessment you aim to minimise sources of variation which could affect your results. This means keeping the same, small number of trained people to do the insect recording, to reduce ‘observer variation’. If you want to involve farmers with the trials, you could invite them to the trial sites to explain what is going on, you can run parallel training and demonstration exercises so they are learning the observation skills and can take part in the results discussion. Host field farmers and/or their teenage children could perhaps help with data recording on paper in the field. The insect sampling method which Robert used in his field trials in Australia involved using professional entomological kit, using sweep nets, beat sheets, vacuum samplers and visual checks. Most of these insect assessment tools (sweep netting, vacuum sampling) may not be realistic for field trials in most developing country cotton contexts, unless run by technicians or a research institute. It requires hands on training for farmers and even technicians in order not to damage the plant terminals. The visual count and beat sheet methods described for smallholders in Chapter 2 are perfectly adequate for
142
robust trials managed by technical staff but you will need to put more time and care into the sampling effort and consistency. Make sure that sampling is done at approximately the same time on each occasion, e.g. between 07.00 to 10.00am, AND sample each of the replicate plots in all the treatments on the same day – otherwise you are introducing more background variation into your data. This means thinking at the planning stage how much observer time you will need to sample all the plots carefully, who should be involved, transport time to and from the plots and what resources you will need. Both visual and beat sheet sampling is recommended for all food spray trials: For example, visual counts should be used to assess larval stage populations of Helicoverpa bollworm spp., spiny bollworm Earias huegeli, pink spotted bollworm Pectinophora scutigera, cotton tip worm Crocidosema plebeian and cotton semi-looper Anomis flava. All these caterpillar pests can hide within cotton bolls and bud terminals and so cannot be dislodged on to the beat sheet. For sucking pests, such as mirid bugs, green vegetable bugs (Nezara viridula) and cotton stainer bugs (Dysdercus sidae), jassids AND beneficial insects, both visual and beat sheet can be used to sample them. For other sucking pests, such as whiteflies, aphids and mealybugs, these are very hard to count visually using the standard sampling protocol when they become numerous. They are not possible to sample using beat sheet, sweep net or vacuum sampling methods. They can sometimes be dislodged by beating but not always and remain hard to count. For these pests, 5 plants from each treatment replicate should be randomly selected and adults and nymphs on 5 leaves from the 5th node below the terminal of each plant should
and express the number of the individual insects per leaf. If aphids, whiteflies or mealybugs numbers rise rapidly and become too numerous to count, you may need to devise a simple, visual grading/scoring measure (e.g. light, medium and heavy infestation) as a proxy for counting. You will need to convert the scores into some form of number when it comes to data analysis. The number values themselves are not important (e.g. more than 100 could mean a heavy infestation, more than 50 is medium and 20 is low), as long as the field observers and the data entry people are consistent. Sampling protocol: Visual and beat sheet sampling should be done on the entire cotton plant (top, middle and bottom branches, leaves, flowers and fruits) in three, randomly selected one metre lengths of cotton rows in each treatment replicate. There will be approximately 5 cotton plants per metre but this will vary according to the planting density. You need to randomly select three sampling ‘stations’ or ‘rows of one metre length each time you go and sample. You can do this using a random number generator, or by pulling numbered pieces of paper out of a hat. Sampling frequency: It is essential to sample twice per week for the relevant period during the cotton growing season, from 4-6 true leaf stage onward (when you make the
143
Chap.5
and nymphs present. If nymphs are hard to see and be counted, use magnifying glasses
Testing the food spray method with farmers
be counted visually by carefully turning the leaf over and counting the individual adults
first â&#x20AC;&#x2DC;prophylacticâ&#x20AC;&#x2122; food spray in the food spray treatment plots). If you do it less often, you will miss data showing when pests are rising, or natural enemies moving in or out, or starting to bring pest levels down. This will make any significant differences between your treatments harder to identify during analysis. You can be flexible on which days you sample, as long as over the season overall you are sampling every three to four days. Think about the human and time resources to achieve this level of sampling at planning stage- it will mean some sampling at weekends or during holiday periods at certain times. If you preserve collected insects from the beat sheet counting, you can be a bit more relaxed about when these are identified and recorded but donâ&#x20AC;&#x2122;t let it build up to become a
spray method with farmers
Chap.5 Testing the food
mammoth task.
Beat sheet sampling: Identifying and counting dislodged insects on the canvas sheet. Credit: R Mensah.
144
5.3.2 Sampling in relation to food sprayed and control treatments Organising and sampling the food spray treatment: You want to look for differences before and after applying a food spray and compare this with levels of pests and natural enemies in the non-food spray control treatments (either unsprayed and/or a chemical treatment). So it makes sense to do your very first sampling just before you make the first food spray at 4-6 true leaf stage. You will need to sample the same date on your control treatments so that you get an idea of the starting, early season background or baseline natural enemy levels (and their natural variation). You should apply this first food spray to all the replicates for the food spray treatment plots. Your next sample will be three or four days later, when you might start seeing changes in natural enemy numbers. NOTE: there can be several days, or more, of time lag between applying a food spray and when you start to see predators attracted in. Your next food spray should only be applied when your counting has shown that the Predator to Pest ratio has dropped below 0.5 in at least one of your food spray treatment replicates (i.e. more than double the number of pests to natural enemies). You will apply the food spray to all the replicates in the food spray treatment plot at that site. Other trial sites are their own separate world for decision making. Try to organise the food spray application as soon as possible after the sampling date which showed the unfavourable ratio, because that is what you would encourage a farmer to do. If you follow the twice per week sampling protocol, you will sample again between one and four days after the counts-based food spray applications. It doesn’t matter too much when and over
(a) Insecticide chemical control treatment. If you decided to include a conventional chemical treatment in your comparison trial, either as part of the randomised block design, with appropriate replicates and separation to minimise drift, or in separate fields some distance away, you should apply a standard recommended application regime, or copy what is happening in the main fields of the large farm. For smallholder chemical treatment, you can find out and copy a local ‘average’ or ‘typical’ application frequency and active ingredient choice. You will apply these insecticide sprays irrespective of what is going on in the food sprayed treatment plots but you will sample these insecticide-treated plots at least 3 days after insecticide application to count pest and natural enemies on the same dates and in exactly the same way as in the food sprayed plots, but keeping the samples separate and labelled. Over the season, you will end up with some sampling dates fairly soon after an insecticide application and some only several days or even weeks later, so you will get a good idea of what happens to total pest and natural enemy numbers (and most frequently observed particular groups) following insecticide applications and be able to compare this data with the trends in the food sprayed plots.
145
Chap.5
Organising and sampling the ‘control’ treatments:
Testing the food spray method with farmers
the season you will get a representative range of post-spray count data.
(b) Unsprayed control treatment. It is often useful to include an unsprayed treatment, both in conventional cotton and organic contexts. This no-spray treatment will give you the best idea of which natural enemies come into the crop of their own accord when insecticides are not used and at what levels and the trends over time, as well as the pest levels and damage in unsprayed cotton. This no-spray treatment should be replicated, laid out and sampled in the same way and on the same dates as the food sprayed treatment. You can then assess what additional natural enemy types and numbers you attract in when applying food sprays, by comparing data and trends in the food sprayed and unsprayed treatments.
We have discussed throughout this manual the importance of using the food spray method as part of an integrated system with other IPM methods. Nevertheless, you probably donâ&#x20AC;&#x2122;t want to over-complicate small trials to try out the food spray attraction performance by adding in the additional IPM methods at this stage of research. It will be easier to do this later or in larger comparison trials of the food spray in an integrated system, compared with whatever is local, current farmer practice, including the economic
spray method with farmers
Chap.5 Testing the food
assessment.
5.3.3 Data collection and data entry Counting the insects: Visual counts at early stage cotton, when the plants are small and the insect numbers low, can be easily recorded onto paper monitoring sheets direct from the field counting. It is easiest if one or two of the trained team do the observations and call out the names and numbers to a â&#x20AC;&#x2DC;scribeâ&#x20AC;&#x2122; who fills in the appropriate figures in a field monitoring template sheet prepared for this purpose. It may be easiest to have a separate and labelled data recording sheet for each treatment (and for each site, if you are carrying out trials at more than one site). See Annex III for data collection sheet templates for beneficial insects and pests, as used in the Ethiopian trials for hard copy data recording in the field, based on the most commonly observed pest and beneficial groups at the Arba Minch sites. From mid-season onwards, when you get taller plants, with many more insects present, and more fruiting branches and fruits to check, you will start using the beat sheet method, as well as visual inspection of the plants. At this stage, it is probably easier to collect the insect samples from the beat sheets and take these back to the lab or office to separate
146
into groups and count and record these in the cool and shade. Collect in separate plastic bags for pests and natural enemies, labelled by treatment and by replicate plot. Have a suitable container to transport them and don’t let them melt or fry in the sun and become hard to identify! You can also collect into small preserving vials containing alcohol if you prefer.
Checking the balance between pests and natural enemies: Following the first food spray application, the data observation team will need to be checking when any replicate plots in the food spray treatment exceed the unfavourable balance level of ‘more than double the number of pests to natural enemies” (at or below Predator to Pest = 0.5) because this is the decision trigger for another food spray. The field staff can easily see from the raw data they collect when pest numbers are more than double natural enemy numbers in a particular replicate. It is not necessary for them to calculate the ratio in mathematical terms (that is quicker and easier to do in the spreadsheet) but they should, of course, highlight on the sheets when the balance has become unfavourable. A comments box on the sheet for each replicate per sampling date is useful and data observers might like to note relevant information, e.g. “pest numbers rising in replicate C but not yet at the ratio for food spray application”.
Identifying the insects: It is sufficient to group natural enemies into:
Chap.5
Testing the food spray method with farmers
predatory beetles predatory bugs lacewings hoverflies spiders predatory ants With some supervision and practice, field agents can soon learn to distinguish different types of predatory beetles and bugs at Family level, e.g. ladybird beetles, ground and rove beetles; red and blue beetles; green soldier (cantharid) beetles; shield bugs, damsel bugs, assassin bugs, big-eyed bugs. It is not essential to identify these to Genus or Species level, but if you have friendly entomologists to help, that is a bonus. If you consistently find a particular type of one of these groups, that seems to be important in controlling pests, you might want to send preserved samples plus photos of it (live in the field) to a national expert to identify to species level. It’s always good to take lots of clear, close-up photos of the pests and natural enemies you observe, as you can use these in farmer training materials. Don’t forget to take photos of their larval stages, possibly eggs and pupae too if you find these.
147
5.3.4 Recording the data Using standard printed copies of data collection template sheets, written in appropriate local language, will make data collection and recording in the field and in the office much easier. Keep these consistent to make the rather tedious task of data entry easier for the people involved, e.g. decide on a fixed order of names for the main pest species you are likely to observe (e.g. aphids, jassids, whiteflies, African bollworm, pink bollworm, etc.) and stick to the same order for all the sampling dates. Likewise for natural enemies. You can have some blank rows in both pest and natural enemy sections of the recording sheet to allow for ‘Others’ and then write by hand what these are, if you know, or you can record as, for example, ’ unidentified red bug’. To assess the trial data properly, you will need somebody who is familiar with spreadsheets to: ¬ organise the appropriate calculations, e.g. of Predator to Pest Ratios
¬ generate graphs and time-line visual representations of the data
¬ conduct the statistical analysis (either by a statistician or in close liaison with one)
weekly sampling into a spreadsheet set up for this purpose (by somebody who spray method with farmers
Chap.5 Testing the food
But the first step is to enter the raw data, usually recorded on paper, from your twice understands what the trial involves, how many treatments and replicates, etc.) You may have a field agent or clerical staff member to enter this data. It is a rather boring and time consuming task which requires patience and accuracy, so don’t leave it all till the end of the season or do a rushed job because mistakes will creep in and reduce the quality of your data. Get it done carefully every couple of weeks so it doesn’t become too tedious or mount up. The need to record raw data from individual replicates: It is very important to appreciate that the data entry people and the analysts will need the separate counts of pests and natural enemies from each replicate in each treatment for each sampling date, so don’t lump them all together when you record the data on paper. If the data for African bollworms are only recorded as a single total for the three replicate plots in your food sprayed treatment, for example, rather than three separate subtotals, the analyst won’t be able to do the statistics because they cannot ‘see’ the variation between those three replicate plots. But within each replicate you do make a total count from the 3 separate one metre length sampling stations to form one single value, for example, Z predatory beetles observed on date A for plot replicate B in treatment X.
148
5.4
Evaluating the food spray and control treatment
Your aim is to look for and understand any significant differences between the food sprayed and the control treatments (unsprayed and/or insecticide sprayed) in terms of pests and natural enemies numbers in small scale trials studying whether the food spray component works. You can also include yield in your data collection in these trials although it may not make statistical sense to analyse for significant differences because the yield will have many contributing factors and a lot of background variation across plots if these are separated by considerable distances.
5.4.1 Making time-line graphs of pest and natural enemy numbers (density per metre) Before you start with appropriate statistical analysis, guided by somebody with statistics expertise, you can make graphical representations of the data, using the completed spreadsheets. To do this, you want the spreadsheet to convert the raw data entered from your twice weekly sampling for pest numbers per metre and natural enemy numbers per metre into cumulative totals across the season. This cumulative density is what you will later assess for significant differences using suitable
metre) for each treatment. Indicate by arrows when food spray or chemical treatments were applied. It can be informative to do this too for specific key pests and key natural enemy groups you are interested in. Figure 5.1 gives an example from one of the Ethiopian FFS trial sites, showing graphs for ladybird beetle (coccinellids) and lacewing (chrysopa) densities in the six different treatments tested. Note that it is very hard to read when the graph is in black and white so use different colour lines for the different treatments. Understanding the graphical representations: When you graph insect density per metre over the season and indicate with arrows when food sprays (or insecticides) were made, you can get a good idea of how the relative numbers of pests and predators goes up and down and how these are affected by pest management actions. NOTE: you donâ&#x20AC;&#x2122;t always see an immediate increase in natural enemies or a decrease in pest numbers after a food spray application - it can take a week or more for predator levels to build up and start consuming pests. Sometimes you see a rapid increase in natural enemies, i.e. the food spray has probably helped to attract them in,
149
Chap.5
can now generate timeline graphs for total pest and total NE density (numbers per
Testing the food spray method with farmers
statistical methods. NOTE: you do NOT do any stats on the Predator to Pest ratio. You
but it takes them more time to start to bring down pest numbers. You may sometimes see the lines go in the ‘opposite’ direction from what you expect, e.g. natural enemy numbers dropping after a food spray. Pest control performance depends also on what stage key predators are at. For example, many ladybirds could be pupating when you sampled on
spray method with farmers
Chap.5 Testing the food
that date, so it may take some days before they emerge as adults and resume feeding.
Food spray trial plots at Chano Mille FFS demonstration site, Ethiopia. Credit: PAN UK.
It is very hard to just look at the trends in the time-line graphs of pest or predator densities and see which treatments might show significant differences. This is why you need the stats support to do this (see section 4.3.3). The time-line graphs, however, can be useful to tell a ‘visual story’ of what happened to pests and natural enemy levels over the season in a particular treatment and to see if you got a consistent response in pest and natural enemy levels following each food spray or insecticide application.
150
Fig 5.1. Timeline graphs of natural enemy density from one FFS trial site in Ethiopia.
B e n in F o o d s p r a y a lo n e B e n in F o o d s p r a y + N e e m e x t r a c t E t h io p ia F o o d s p r a y a lo n e E t h io p ia F o o d s p r a y + N e e m e x t r a c t
A N o . c o c c in e llid s p e r m e t r e
*
*
N e e m e x t r a c t a lo n e
10
U n t r e a t e d ( c o n t r o l)
*
8
6
*
4
2
5 O ct 2013
19 S ep t 2013
3 S ep t 2013
28 A u g 2013
15 A u g 2013
7 A u g 2013
19 Ju l 2013
16 Ju l 2013
0
B e n in F o o d s p r a y a lo n e B e n in F o o d s p r a y + N e e m e x t r a c t E t h io p ia F o o d s p r a y a lo n e
N e e m e x t r a c t a lo n e U n t r e a t e d ( c o n t r o l)
*
4
*
* 3
2
1
5 O ct 2013
19 S ep t 2013
3 S ep t 2013
28 A u g 2013
15 A u g 2013
7 A u g 2013
19 Ju l 2013
16 Ju l 2013
0
D a te s o f a s s e s s m e n t
Source: Amera et al. (in press). Trial laid out in plots on one smallholder farm at Shelle Mella in Southern Ethiopia Rift Valley, 2013. Lines show ladybird (A) and lacewing (B) density per metre over the season. Arrows indicate dates of treatment application. Error bars indicate standard error of the mean. * indicates significant difference among treatments (level of significance is given in the text).
151
Chap.5
5
Testing the food spray method with farmers
N o . c h ry s o p a s p . p e r m e tre
E t h io p ia F o o d s p r a y + N e e m e x t r a c t
B
5.4.2. How to make use of the Predator to Pest ratio data The Predator to Pest balance is part of the decision making process in the field during your trials and for this, the raw numerical data is sufficient. However, it is very useful to calculate the Predator: Pest ratio in your spreadsheet and to make graphical representations of the trends, highlighting: ¬ when the ratio became unfavourable in the different treatments ¬ when food or insecticide sprays were applied Printing these graphs out and showing them to farmers can be educational so they can follow the trends and (hopefully, if your trials ‘worked’) show what happens to the balance between pests and natural enemies in fields that encourage the latter through food spray attraction and zero pesticide use compared with fields with insecticide spraying. Bear in mind that in many conventional cotton farms, large or small scale, farmers use more than one specific insecticide active ingredient so your analysis is not going to give you the impact of a specific insecticide on a specific pest and/or natural enemy, rather an
spray method with farmers
Chap.5 Testing the food
indication of the overall insecticide ‘burden’ or toxic load.
Records of pest, beneficial insects and fruit retention from the farmers’ observation Credit: PAN Ethiopia.
152
5.4.3 Using the data for statistical analysis For analysis, Robert Mensah has assessed in his research trials the graphical time-lines for insect density described above and the following statistical assessments of significant differences: o
Are there any significant differences between treatments on cumulative density (numbers per metre) over the season? (not on average density and not on Predator: Pest ratio). You can do this for total pests and total natural enemies, also on specific key groups you are interested in.
o
Are there any significant differences in total pest or predator density or of particular groups per treatment at different dates over the season?
The best way to do this is to analyse the data using dates after treatment. You have pretreatment counts, then post treatment counts. You can analyse the data on each sampling date until your next spray. Table 5.1 gives an example from the same Ethiopian FFS trial site and sampling period as the graphs in Figure 1 above but showing the average (mean) number per metre of four different predator groups per sampling date and the range (standard deviation). It is possible to analyse these for significant differences, as has been done in this example (using the raw data for each replicate in each treatment on each sampling date). In this case, for ladybirds and lacewings, both food spray recipes alone attracted in significantly higher numbers than the treatments including neem or the unsprayed control.
Chap.5
Testing the food spray method with farmers
153
Table 5.1. Effect of different treatments on total numbers per metre of four predator groups at Shella Mella from 15 July – 5 October 2013 Treatments
No. per metre per sample date Coccinellids
Lacewings
Spiders
Ants
2.00 ± 0.41a
0.63 ± 0.22 a
2.58 ± 0.50 ac
9.33 ± 2.70 a
Benin Food spray + Neem extract
1.25 ± 0.36 ab
0.13 ± 0.07 b
1.46 ± 0.28 b
4.00 ± 0.99 b
Ethiopia Food spray alone
2.00 ± 0.39 a
0.79 ± 0.28 a
3.42 ± 0.45 a
8.67 ± 2.00 a
Ethiopia Food spray + Neem extract
1.13 ± 0.28 ab
0.25 ± 0.11b
1.38 ± 0.22 b
4.00 ± 0.95 b
Neem extract alone
0.33 ± 0.12 b
0.00 ± 0.00 b
1.08 ± 0.20 b
2.42 ± 0.72 b
Unsprayed (control)
0.91 ± 0.32 ab
0.17 ± 0.08 b
2.17 ± 0.35 bc
4.08 ± 1.08 b
P (ANOVA)
< 0.0002
< 0.0001
< 0.0001
< 0.0001
Benin alone
Food
spray
Source: Amera et al. (in press). Means within a column followed by the same letter are not significantly different (ANOVA with no significant treatment effect (P > 0.05).
spray method with farmers
Chap.5 Testing the food
It is not possible to give more guidance here on appropriate statistical methods as trial layouts, data collection, treatments and research questions will vary. Make sure you consult with a statistically literate person at your trial planning stage and collect and record your data in a format that this person will be able to work with. Don’t try to feed your data into standard stats software packages yourself, unless you really know what you are doing and are confident you have selected the appropriate analytical method for your trial design and questions.
154
5.5
Economic comparisons between integrated food spray systems and farmers’ practice
These are some of the most useful trials in terms of generating data which will help convince farmers and others to change their pest management practices. You will want to collect data and measures between: o
the food spray method (possibly integrated with other IPM methods too)
o
a locally relevant conventional insecticide regime
o
possibly a ‘no spray’ or ‘no agrochemicals’ management system, if smallholders are mainly ‘organic by default’, using their current agronomic practices
To make a decent cost comparison between these systems, you need to record and compare:
Detailed, itemised ‘product’ cost of food spray application (including preparation time)
Cost for number of applications per ha per season at site X
Detailed, itemised cost for insecticide application
Cost for number of applications per ha per season at site X
All other annual production costs
Service costs, e.g. ploughing or equipment hire Input costs, e.g. fertiliser, cotton seed Labour costs
Cotton yield data
Cotton seed in kg per ha
Cotton revenue obtained
Cotton price per kg seed cotton x yield obtained per ha at site X
Net income
Total revenue minus total production costs
155
Chap.5
Measure
Testing the food spray method with farmers
Item
Donâ&#x20AC;&#x2122;t forget to include the preparation, as well as the application time, labour costs if using hired labour and any sprayer rental charges when you are making an economic comparison of use of food sprays in an IPM trial with conventional cotton. These application costs are likely to be very similar whether you are applying food spray or insecticides. IPM farmers still using insecticides will need to obtain separate, uncontaminated spray equipment just for the food spray so there will probably be an initial investment cost to include. It is good practice to document separately all the relevant unit or item costs for the different treatments, in local currency and units, but making sure to include current conversion rates so that people outside your country can understand the data. You can use the costs data to calculate costs and revenue per treatment plot area, as your trials may well be on plots less than one hectare in size. However, to discuss and disseminate the results with stakeholders beyond the project, these need to be converted into per hectare figures. Take care with yield conversions from hand-picked cotton trials on small plots, that when you extrapolate these to hectare equivalents you are not grossly over or underestimating yields. Standard conversions either use Plant population densities x Plot sizes; or Seed cotton lint per particular variety x Seed cotton weight picked. You can also use the number of bolls per metre; seed cotton weight per metre; or conversion factor from seed cotton yield to lint yield. Local cotton agronomists or researchers should be able to advise on a
Having tailor-made template sheets for recording the basic data and values for each spray method with farmers
Chap.5 Testing the food
suitable conversion method.
treatment at each site should help with accurate data collection. It is easy for mistakes to get made at the economic assessment stage with units used, yield and conversion rates or basic data entry. Get somebody to double check all your units, conversion rates and calculations! If yields look amazingly high or low, somebody has probably made a mistake somewhere. As an example, Table 5.2 compares the yields, revenues, total pest control and fertiliser costs and related gross margins from an economic assessment in the second year of food spray trials carried out with smallholders in Benin (see Chap 1.4.2. While the conventional cotton delivered the highest yield, the agrochemical input costs for this treatment were very high too and the highest gross margin was, in fact, from the food spray treated organic cotton.
156
Table 5.2. Economic comparison for organic cotton managed with food spray, with neem and with conventional cotton, Benin trials, 2007 season. Treatment
Seed cotton yield (kg/ha)
Total revenue from lint sales
Total pest control & fertiliser costs
Gross margin in terms of pest control and soil nutrition
Organic cotton managed with Benin Food Product
805 ± 87.77 a
164,220
38,880
125,340 ± 533 a
Organic cotton managed with neem
562 ± 86.38 b
114,648
34,400
80,248 ± 896 b
Conventional insecticide treated cotton
1,145 ± 78.67 c
194,650
105,200
89,450 ± 412 c
Untreated organic cotton control
17 ± 15.67 d
3,468
2,500
968 ± 250 d
Source: adapted from Mensah et al. 2012. Costs in FCFA (US$ = 483 FCFA in 2007 season). Seed cotton price for organic cotton was 204 FCFA/kg and 170 FCFC/kg for conventional cotton. Means within each column followed by the same letter are not significantly different (P> 0.05, Tukey-Kramer multiple comparison test).
Chap.5
Testing the food spray method with farmers
157
5.6
Interpreting trial results and drawing conclusions
Presenting the results for discussion: Once you have completed the graphical representations and the stats analysis, you can sit down with the research team and participating farmers and discuss the findings and reflect on what this means for your joint work. Present the results in a simple manner on flipcharts in as visual a way as possible, so that you can facilitate farmersâ&#x20AC;&#x2122; active participation in discussing what the results mean, the key learning points and possible next steps to take in the following season. Farmers will be most interested in results in terms of yield and costs so make sure to think together about the various natural and man-made factors which could also influence yield results. Donâ&#x20AC;&#x2122;t jump to conclusions based on what you think or hope should happen but base these on the evidence from the field data, bearing in mind any compromises or difficulties encountered in your trial design or conduct. Will these tend to underestimate or over-estimate the food spray effect on natural enemies? Make clear your assumptions when interpreting the results and be ready to consider alternative or other contributing partial explanations for what you observed. Taking a broader approach to evaluation than just economics: The economic comparisons will be of interest to everybody, but donâ&#x20AC;&#x2122;t forget to make a broader evaluation and get participants to think about hidden costs and benefits that are hard to
spray method with farmers
Chap.5 Testing the food
measure in economic terms: o
What are the hidden costs of using HHPs in local conventional cotton systems?
o
Which system helps best to protect human health?
o
Which system helps to conserve biodiversity and valuable ecosystem services of natural pest regulation, pollination, nutrient cycling, healthy soil function, water retention, flood regulation?
o
Which is more likely to be resilient in the face of extreme weather events, climate change?
o
Which will be more likely to still deliver good crops and a profit for the next generation running the farm?
158
Telling others about the findings: You will probably want to present and discuss the trial results with relevant organisations, including farmer groups, extension services, local government agencies, national ministries, researchers, NGOs and cotton companies. These discussions can include looking at the value, costs and benefits of using the food spray method in different cotton systems, further research needs and training aspects. An ‘Open Day’ in the field at the end of the growing season is a good outreach channel, to which you can invite selected guests and organisations you want to influence. Getting trained farmers to present some of their results is a powerful tool for persuading policy makers and other farmers to take notice. Writing scientific reports and papers: If you plan to prepare a scientific paper for publication from your work, reflect honestly and carefully about the shortcomings and compromises taken in your trial designs, treatment choices, data collection and assessment. You should be able to get your manuscript to the level acceptable for an international peer-reviewed journal as long as you: ¬ Explain and justify any weaknesses and necessary trade-offs in the trial design and lay-out (especially regarding the challenges in avoiding food spray odour plume treatment ‘overlap’) ¬ Make clear your assumptions made and how you did the analysis ¬ Write openly about the difficulties of drawing very concrete conclusions
countries is that cotton farmers need to be encouraged by training, demonstration plots and awareness-raising to make the first prophylactic food spray. They should be helped to understand that the method is not about replacing a harmful pesticide with an alternative, safer ‘product’ (the food spray) but involves learning that the crop environment, surrounding shrubs, trees, and other crops in the area to be free from broad-spectrum synthetic insecticides so that these habitats can become a source and refuges for beneficial insects. The habitat manipulation component is not an ‘optional extra’ but an integral part of the biological control enhancement approach. Hence, farmers using food sprays should try to convince their neighbours or owners of adjacent cotton fields to use food sprays too, rather than rely on conventional insecticides. Discuss and plan with farmer groups and cotton support staff which further training needs they have identified on safer, ecologically sound cotton production methods, in order to improve the knowledge and skill base of farmers, project counterparts and field agents. These may include more on techniques for growing a healthy cotton crop; keeping track of insects (monitoring, sampling, plant damage, fruit retention); conserving beneficial insects; making effective pest control decisions; preparation and effective use of food spray products. 159
Chap.5
Promoting the food spray method: Robert Mensah’s experience in Australia and other
Testing the food spray method with farmers
¬ Don’t ‘over-claim’ on any differences observed, especially in yield terms
5.7
Testing the food spray method in other crops
As far as we know, there is no documented research experience in testing the food spray method in crops other than cotton. In Robert’s judgement, there is no theoretical reason why it should not work, if natural enemies are present in the surroundings and can be attracted in at the right time to control problematic pests, by food spray applications and habitat manipulation and avoiding harmful pesticide spraying. Some lead farmers among the Ethiopian smallholders trained since 2013 in the food spray method have reported anecdotally that people have noticed that the maize borders in their food sprayed plots have almost no stalkborer infestation. This could indicate that the food spray is also working to increase natural enemy control on maize but this hypothesis would need to be tested. Several farmers reported that they have tried using food sprays with good results on their vegetable crops, including tomato, but have no quantitative data. PAN Ethiopia and their local Board of Agriculture counterparts are keen to run some proper trials in vegetables so they can find out the best crop stage to apply, which natural enemies attracted and which pests controlled - you can’t just assume it will have the same effects as in cotton. Many FFS ‘open day’ participants and government officers who evaluated the project are interested to expand use to food crops too.
spray method with farmers
Chap.5 Testing the food
Points to consider when planning to test the method on other crops: ¬ Many of the key pests (e.g. African bollworm, aphids) infesting tomato and other crops are the same as those attacking cotton. ¬ There are likely to be many of the same or similar natural enemies in and around vegetable crops. ¬ The same methods may well result in similar positive effects in terms of improved pest control in other crops, as in cotton. It may even work better in other crops than in cotton. Give it a try. ¬ Before you start experimenting with the food spray, it’s best to get a good entomologist to look at the crops, verify which natural enemy groups frequent those crops . ¬ Use the visual counting method to ‘explore’ the natural enemies that visit the crop naturally, in the absence of food spray or of insecticides. ¬ Try the brewers’ yeast recipe first as it works better to arrest, as well as attract natural enemies ¬ To test dose rate, start with the dose used in cotton and then vary the rates if this does not seem effective. 160
An outline plan for testing potential of the food spray method in a vegetable crop could include the following steps and research questions:
Stage 1: Scoping studies Which are the main pests affecting the crop? Are there any minor pests which become major under excessive or frequent application of broad-spectrum insecticides? Which relevant (i.e. useful for the key pests identified) natural enemies are attracted into the vegetable crop when we apply food sprays Is there enough attractive vegetation already or will we need to sow or plant suitable species in field borders, between raised vegetable beds, etc.? Which trap crops might work to â&#x20AC;&#x2DC;pullâ&#x20AC;&#x2122; key pests away from the target crop?
Stage 2: Full trials with smallholders as part of an IPM strategy Try out the food spray methods with a few keen, smallholder collaborators. Try to cover a range of crops and growing conditions, preferably over 2-3 seasons.
enough. Look at ways to introduce or improve the other fundamental IPM principles of growing a healthy vegetable crop and carrying out good cultural practices and field hygiene. Experiment with different options for making the habitat surrounding the vegetable plots more favourable for natural enemies
161
Chap.5
methods wherever possible, for when biological control by natural enemies is not
Testing the food spray method with farmers
Experiment with a variety of complementary IPM methods, preferring non-chemical
Sources of information Amera, T, Mensah, RK and Belay, A. (in press) Integrated pest management in a cotton-growing area in the Southern Rift Valley region of Ethiopia: Development and application of a supplementary food spray product to manage pests and beneficial insects. International Journal of Pest Management Mensah, RK, Vodouhe, DS, Sanfillippo, D, Assogba, G and Monday, P. (2012) Increasing organic cotton production in Benin West Africa with a supplementary food spray product to manage pests and beneficial insects. International Journal of Pest Management 58 (1) 53-64
spray method with farmers
Chap.5 Testing the food
DOI: 10.1080/09670874.2011.645905
162
Useful Reading Learning to Cut the Chemicals in Cotton: Case studies in farmer focused cotton IPM from around the world. PAN UK and CABI Bioscience, 2001. Available from PAN UK. Field guide exercises for IPM in cotton. Vietnam National IPM Programme, 2000. Via: http:// www.vegetableipmasia.org/uploads/files/document/TrainingMaterials/IPM_Cotton.pdf
Chap.5
Testing the food spray method with farmers
163
Chapter 6 Lessons learnt and generating knowledge about the food This chapter serves to sum up the experiences gained from testing and using the food spray method with cotton farmers in Africa and identifies ten key lessons from these experiences. We explore specific contexts in which the methodâ&#x20AC;&#x2122;s three components could provide real benefits for cotton farmers in other developing countries and then look at their relevance in other cropping systems and in agriculture in the developed world. Finally, we encourage readers to share their results and experiences in trying the method in their own
and generating knowledge about the food spray method
Chap.6 Lessons learnt
contexts and offer support on testing, knowledge generation and dissemination.
Participants visiting displayed materials Credit: PAN Ethiopia.
164
6.1
Lessons from experiences in Africa
6.1.1 A viable organic alternative to high-input conventional With almost 10 yearsâ&#x20AC;&#x2122; experience in Benin, the food spray method has now become one of the mainstays of pest management among the 3,000 plus organic smallholders collaborating with PAN partner OBEPAB. Nevertheless, OBEPAB emphasises that the successful uptake of their work in organic cotton cropping systems is due as much to: good training, by staff recruited locally and fluent in local languages; using participatory methods for working with farmers, including attention to women and youth; capacity building for farmer organisations, with open and transparent governance; diversifying crop rotations and looking at improving total farm productivity in the challenging conditions of savannah farming. The three years of practical research and development on adapting the food spray method to the context of smallholders was based on good ecological science and carefully designed and conducted trials. This ecological pest management approach complemented perfectly OBEPABâ&#x20AC;&#x2122;s existing ethos of building on farmersâ&#x20AC;&#x2122; local knowledge and involving farmers as active players in research and helped boost yields to similar levels as those in many conventional farms. By combining all these elements, OBEPAB and its farmer partners have developed a successful and sustainable business model, based on agroecological principles, as an alternative to the paternalistic conventional cotton production model, which continues to rely mainly on calendar-based regimes of up to 8 applications of Highly Hazardous Pesticides per season and does not consider smallholder farmers as capable of understanding or implementing IPM.
Chap.6
Lessons learnt and generating knowledge about the food spray method
165
6.1.2 A new basis for developing profitable organic and IPM cotton in Ethiopia In Ethiopia, when the project began in 2013, organic cotton production was almost nonexistent, either in smallholdings or larger farms, as until then there were no welldeveloped alternative pest management options to conventional chemical control. The experiences in PANâ&#x20AC;&#x2122;s three year FFS IPM training project, including trialling the food spray method, are now stimulating the development of profitable organic cotton production in Arba Minch and generating interest in organic and IPM cotton at national level in policy circles and within the textile private sector. Cotton from FFS trained farmers, with zero use of pesticides, was recently classified as Grade A by the national textile enterprise agency and one of the FFS villages has set up an organic cotton growersâ&#x20AC;&#x2122; cooperative, with support from local government. Organised FFS groups have managed to negotiate better prices from local traders and gain sales contracts at premium prices with textile companies in the capital. PAN Ethiopia is promoting the food spray method as the foundation for biologically-based pest management for high quality and high yielding organic systems suitable for smallholders beyond the Arba Minch area. They aim to persuade more large farms to start on the journey to safer and more sustainable IPM cotton, using the food spray method as the keystone for phasing out use of HHP insecticides, including the persistent organochlorine endosulfan, which is listed on both the Stockholm and Rotterdam Conventions yet remains in widespread use in cotton in Ethiopia, under handling practices which pose high risk to farm workers and non-target fauna. An ecologically sound alternative approach, based on good cultural practices and enhanced biological control, would aim to replace current reliance on chemical control with a range of IPM methods,
and generating knowledge about the food spray method
Chap.6 Lessons learnt
while maintaining or improving yields and profits. Expanding IPM cotton to smallholder and large cotton farms will require not only seasonlong Farmer Field School training to enable farmers and technical managers to gain knowledge and experience in effective use of the food spray method to increase cotton yields but also support to improve profitability by accessing more rewarding and responsible supply chains, such as Better Cotton, Fairtrade and Cotton Made in Africa. PAN UK and PAN Ethiopia will be developing an IPM cotton toolkit for Ethiopia during 2017 to support training of many more extension staff and field agents from the public, NGOs and private sectors to work with farmers on learning how to shift to organic or IPM cotton systems.
166
6.1.3 Ten lessons from testing and using the food spray method with smallholders Lesson 1. The maize-based Benin Food Product recipe is more readily available for smallholders but preparation is time consuming and it cannot be quickly made up for immediate use. However, there should be fairly easy options for mass production for farmer groups using simple, mechanised grinding equipment. The recipe based on waste brewers’ yeast is quicker and easier to prepare and forms a good option for large farms. Lesson 2. The first food spray application should always be made based on crop growth stage and not on the presence of pests or predators. For cotton, a food spray at the 4-6 true leaf stage works best to bring in predators early in the season before the major pests arrive. Lesson 3. Sugar and soap additives and food spray dose rates can be adjusted to meet field-specific conditions, but this requires some experience in using the method over several seasons. For beginners, it is best to use the basic recipes, with sugar and soap added, and apply at the higher dose rate of 2kg food spray ‘concentrate’ per hectare. This will build up enough food spray residues on the leaves to sustain predatory insects. Lesson 4. Field monitoring really needs to be done twice per week, especially during the main pest attack stage from squaring onwards, to enable farmers to make appropriate decisions on when to apply the food spray. This ensures the maximum effectiveness of the food sprays in maintaining a healthy balance of predators to pests. Lesson 5. The habitat management component of the method should not be neglected. For beginners, try the Benin arrangement of 2-3 rows of sorghum or maize planted between every 8-10 rows of cotton (see Chap. 2B 2.6). Lesson 6. It is important for farmers and trainers to understand the ecological basis of the
egg laying on the crop. Lesson 7. Sufficient and good quality training is needed for field agents and farmers on identifying major pests and common natural enemy groups, on field monitoring protocols and on making decisions based on the balance of predators to pests. The simplest version of field monitoring and decision making can be learnt and implemented by poor farmers with low education levels. Lesson 8. The food spray method, especially the food spray itself, is not a magic bullet that will solve all pest problems. In many contexts, the method components will need to be complemented with other IPM methods, preferably non-chemical techniques (biological, physical or cultural controls). Good field sanitation and crop husbandry is an essential part of IPM for any crop.
167
Chap.6
a more favourable balance of ‘farmers’ friends’ to pests, and can also reduce bollworm
Lessons learnt and generating knowledge about the food spray method
three components of the food spray method (see Chap. 1.2) and how these work to create
Lesson 9. The food spray method can help farmers to reduce pest damage and increase yields, at fairly low cost. However, IPM or organic training and implementation is only part of improving farm profitability and smallholder livelihoods. Farmers also need support in group organisation, post-harvest storage and processing, business skills, marketing and linking into more rewarding supply chains. Lesson 10. Try the method for yourself! By documenting and sharing your results and experiences, you will make a valuable contribution to global knowledge about the food
and generating knowledge about the food spray method
Chap.6 Lessons learnt
spray method, especially in crops other than cotton.
Ploughing fields for cotton sowing, smallholder production, Lake Abaya, Ethiopia. Credit: PAN UK.
168
6.2
Expanding use of the food spray method
6.2.1 Relevance to other cotton production areas and systems PAN UK, its partners in Benin and Ethiopia and Dr Robert Mensah all consider that the food spray method has immediate relevance for cotton growers, large or small scale, in many parts of the world. It would be very timely and informative to trial the method, including the components of habitat management and avoidance of broad-spectrum insecticides, in the following contexts, as examples: In northern India and Pakistan cotton systems: as a safer and more sustainable alternative to the cocktail mixtures of HHP insecticides which many farmers have resorted to in recent seasons to combat very damaging whitefly outbreaks. Part of the reason for these outbreaks is excessive and totally inappropriate use of broad-spectrum insecticides, some of which are no longer effective against whitefly, as well as problems related to high whitefly susceptibility of many of the B.t. cotton cultivars available in this region. Some farmers are returning to cultivation of local, desi cultivars of non-B.t. cotton, which seem to be less prone to pest attack â&#x20AC;&#x201C; integrating the food spray method with less susceptible cotton cultivars, good cultural practices and less harmful, other IPM practices (e.g. pheromone traps, biopesticides, semiochemicals for changing pest behaviour, ) could help farmers in India and Pakistan make a significant shift away from reliance on HHPs and on B.t. cotton, while improving yields and profits and the health of those working in cotton fields. In East African cotton systems: cotton is an important crop for smallholders and part of the large farming sector in Ethiopia, Tanzania and Uganda. The food spray method could help improve yields of the many organic cotton cooperatives, as has been the experience
cotton pests in recent years. Integrating the food spray method with improved field hygiene and other cultural control practices to tackle mealybug infestation points could provide a useful solution to this pest management challenge. In West African cotton systems: much of the francophone countriesâ&#x20AC;&#x2122; cotton production remains wedded to outdated calendar spray regimes or more targeted pest control systems based on scouting and economic thresholds. Both are reliant on frequent application of broad-spectrum insecticides, in smallholder and in estate production. Using the food spray method could enable farmers to stop using the most harmful insecticides, as part of moving to more sustainable IPM systems based on ecological principles. With effective farmer training, use of participatory learning and research methods and empowerment of farmer groups, West African cotton supply chains could be transformed into more efficient and prosperous production for all those involved in cotton growing.
169
Chap.6
conventional or IPM sector. In some parts of the region, mealybugs have become serious
Lessons learnt and generating knowledge about the food spray method
in Benin. It also has potential for improving productivity and sustainability in the
Other cotton production areas: there is already interest in the food spray method from technical support organisations working with farmers to produce Better Cotton, in regions as diverse as southern Africa, Turkey and central Asia, and Egypt. In theory, the method has much to offer in these production areas, whether in smallholder lowinput cotton, or IPM systems (with or without B.t. cotton) in larger farms. Could food spray also be used to complement IPM on commercial conventional and B.t. cotton crops in developed countries?
6.2.2 Crops other than cotton To date, PAN UK has received expressions of interest in the food spray method from several organisations working with smallholder horticulture production in developing countries, and also in food staple crops (cereal grains) for food security projects. In theory, the method should be applicable but very little research has been conducted. Subject to funding, PAN UK is planning a number of trials in different crops and cropping systems. Vegetable production: In rural and peri-urban horticulture, smallholders very often rely on very frequent applications of a range of HHPs, whether they are growing for local or export markets. It would be useful to test whether the method could help reduce reliance on chemical control in vegetable cropping and enable IPM methods to replace most or all use of harmful insecticides, with benefits for farmer and consumer health, and farm profitability. These systems are rather different from cotton fields in their surrounding habitats, crop lay-out and husbandry practices. One important question would be whether
and generating knowledge about the food spray method
Chap.6 Lessons learnt
there is adequate natural vegetation to provide a refuge for and sources of natural enemies, and if not, how could growers plant trap crops, field borders or other suitable vegetation? Other questions will be: when should a grower apply food spray onto different horticultural crops?; and what is the most effective predator to prey ratio on these crops to produce economic yields? Cereal and legume staples production: In smallholder production, these crops are often managed with limited or no use of pesticides, especially in cereals, as much is grown for domestic use or sold in local markets at prices that make agrochemical inputs unaffordable. Could the food spray method help increase natural enemy activity in these crops and contribute to better yields? Fruit and other tree crop production: Orchard systems often already have quite diverse natural vegetation in and around the trees, and may already host significant numbers of natural enemies. Could the food spray method be used to help attract predators to pest hot spots or bring them in early in the season to prevent key pests reaching problematic levels? Would it be feasible economically or technically to apply the food spray to tree foliage? 170
6.2.3 Relevance in developed country agriculture The food spray method was originally developed for use by large scale cotton farmers in high input systems in Australia in the 1990s. The value of its three components in enhancing biological control and helping farmers reduce use of harmful broad-spectrum insecticides is very relevant in current contexts where farmers are under pressure from policy makers to reduce pesticide contamination and impacts on non-target organisms and responsible food companies and retailers are looking to reduce pesticide use, risks and residues. Insecticide resistance problems exist and many pesticide products are being withdrawn from the market in Europe, North America and Australasia. Could the food spray method play a role in helping to â&#x20AC;&#x2DC;replaceâ&#x20AC;&#x2122; with biological control some of the pesticides which are coming off the market or face restrictions in use? Could it help reduce pest resistance pressure by providing an effective non-chemical method in the IPM toolkit? Very topical cropping systems in which to trial the method would be in oilseed rape, sunflower and other arable crops attractive to bees, which in Europe are no longer permitted to be seed treated or foliar sprayed with three neonicotinoid active ingredients. Organic and agroecological cropping systems in industrialised countries could also benefit potentially from use of the food spray method, widening the pest management options for farmers who use minimal or zero synthetic pesticides.
Chap.6
Lessons learnt and generating knowledge about the food spray method
171
6.3
Generating new knowledge and sharing experiences
The rationale for this trainersâ&#x20AC;&#x2122; guide is to encourage more people to try out the food spray method in different areas and different cropping systems. PAN UK warmly welcomes any technical reports, news of work in progress, trials results and feedback from farmers, agronomists, extension agents, researchers and food and fibre sector standards, companies and NGOs who are experimenting with the method components. We will host summaries and other relevant documents on a section of our website to make sure that new knowledge, useful experiences and lessons can be shared. Along with Dr Robert Mensah, PAN UK and its partners OBEPAB in Benin and PAN Ethiopia are available to provide technical and training support on a consultancy basis for
and generating knowledge about the food spray method
Chap.6 Lessons learnt
any organisations who would like to trial the food spray method.
172
PAN UK can be contacted via: Dr Stephanie Williamson, Staff Scientist, email: stephanie@pan-uk.org
PAN Ethiopia can be contacted via: Tadesse Amera, Director, e-mail: pan.ethiopia@gmail.com
Dr. Robert Mensah Senior Principal Research Scientist | Biopesticides & IPM | Director, Australian Cotton Research Institute Department of Primary Industries 21888 Kamilaroi Highway | Locked Bag 1000 | Narrabri, NSW 2390 AUSTRALIA Tel: +61 2 67991525 | M: +61 (0)417146305; +61 (0)429992087 Email: robert.mensah@dpi.nsw.gov.au Web: www.dpi.nsw.gov.au
Chap.6
173
Lessons learnt and generating knowledge about the food spray method
Dr. Ir. Davo Simplice VODOUHE, Coordinator, OBEPAB, 02 BP 8033 Cotonou, BENIN. Email: dsvodouhe@yahoo.com Tel: +229 21 35 14 97 / +229 96 69 10 96 wWeb: www.obepab.bj
Annex I Simple template for insect recording for farmer training This template is suitable for use in farmer learning groups or for extension staff learning the basics of recording beneficial and pest insects.
NOTE: There might be more or fewer than 5 plants per metre length, depending on the planting density in the field to be sampled. You can adjust the recording sheet template according to the average number of plants per metre
Annexes (I)
in your site.
174
Plant number (PN)
Farmers’ friends (Beneficials)
Farmers’ enemies (Pests)
1st metre length observed PN1 PN2 PN3 PN4 PN5 Total 2nd metre length observed Plant number (PN)
Farmers’ friends (Beneficials)
Farmers’ enemies (Pests)
PN1 PN2 PN3 PN4 PN5 Total 3rd metre length observed Farmers’ friends (Beneficials)
PN1 PN2 PN3 PN4
175
Farmers’ enemies (Pests)
Annexes (I)
Plant number (PN)
Annex II Conducting Agroecosystem Analysis in Cotton The information in this annex is adapted from the FFS trainers’ guide on Field Guide Exercises for IPM in Cotton of the Vietnam IPM National Programme and aims to give readers of this manual an idea of the regular cotton crop observation and decision making which farmers learn to carry out as part of FFS training. NOTE: AESA is a separate activity from the field monitoring to assess the balance between Predators and Pests for the purposes of using the food spray method. AESA was developed for FFS training in a variety of crops. Nevertheless, AESA contains some elements of observing levels of pests and natural enemies in the field and discussing their population trends and using this information to help make decisions on what pest management actions may be needed. In Farmer Field School training, Agroecosystem Analysis (AESA) is done weekly in subgroups of 5-6 farmers, supported by the FFS facilitators (extension staff or FFS graduate farmers trained to lead FFS training). FFS participants will need considerable support in the first few weekly sessions when this activity is new for them but after several weeks they soon become practiced and skilled. Some sub-groups will be observing in the usual Farmers’ Practice plots (whether managed under conventional chemical control or not) and others will be conducting the analysis in IPM plots. The aims of conducting weekly AESA (or cotton ecosystem analysis, CESA) are to: ¬ Help farmers learn the observation skills and analytical skills to help them make better decisions on pest and cotton crop management in their own fields
Annexes (II)
¬ Enable the learner group to compare the crop health in the Farmers’ Practice versus IPM Practice plots each week and over the season
The results of each sub-group’s field observations are drawn on a large piece of paper. The drawing is then used for discussion (questions for different stages of the cotton crop growth are available) and the results are presented to the other sub-groups. Everyone is encouraged to be involved in the observations, drawing, discussion, and presentation. It takes around 2 hours to carry out the observations, make the drawings and discuss these, however, as farmers gain experience, the time needed will reduce.
176
Materials: (per group) Newsprint, pencil, crayons, marker pen, graphing paper, plastic bags Method for each sub-group: 1. Go to the field. Walk diagonally across the field and randomly choose 20 plants (every 5 meters) on the diagonal. For each plant follow this examination process and record your observations. Each group should do this on their basic experiment plots.
2. Select three leaves from the plant, one taken from the top, one from the middle, and one from the bottom of the plant. Pick or turn the leaf and count the number of jassids (ignore the other sucking pests if not common).
3. Count the total number of fruiting parts. â&#x20AC;˘
4. Open the bracts of each individual fruiting part and record: number of fruiting parts with bollworm damage
â&#x20AC;˘
number of bollworm larvae
â&#x20AC;˘
any predators
5. Note also: Disease: Notice the leaves and stems. Are there any discolorations due to diseases? (Ask the trainer if uncertain). Estimate the percent of the leaf/stem area infected. Record all observations. Weeds: Note the type of weeds in the field and the corresponding density. Other insect pests: Count the number of each type
6. Uproot one cotton plant for drawing.
7. Find a shady place to sit as a group. Each group should sit together in a circle, with pencils, crayons, data collected and the drawing of the field ecosystem from the previous week.
177
Annexes (II)
Natural enemies: Count the number of each type of predator and parasites.
8. Now make a drawing of the agroecosystem observed on newsprint. Everyone should be involved in the drawing. There are several rules for drawing as follows: a. Draw the plant with the correct number of branches. Draw shedding fruiting parts in yellow. If the plant is healthy, color the plant green. If the plant is diseased or lacking nutrients (low in fertilizer) then color the plant yellow. Draw dead or dying leaves in yellow. b. For weeds, draw the approximate density and size of weeds in relation to the size of the cotton plant. Draw the kind of weeds in the field (broad-leaf or grass type) next to the plant. c. For pest population intensity, draw the insect on the right side of the plant but in the area (top, middle or bottom of the plant) where usually found. Write the number of each next to the insect and then add to get their total and the average per plant. The data can also be summarized in a table on the right side. d. For natural enemy population intensity, draw the insects and spiders as found in the field on the left side of the plant. Write the average number of natural enemies and their local names next to the drawing. e. If the week was mostly sunny, add a sun. If the week was mostly sunny and cloudy all day for most of the week, put a sun partly covered by dark clouds. If the week was cloudy all day for most of the week, put just dark clouds. f. If the field was fertilized, then place a picture of a hand throwing N's, P's or K's into the field depending on the type of fertilizer used. g. If insecticides were used in the field, show sprays with a nozzle and write the
Annexes (II)
type of chemical coming out of the nozzle.
178
9. Below the drawing, provide space for general information, observations and recommendations. a. General information includes the age of the plant, type of insecticide applied, variety planted, fertilizer used. b. Observations include the general situation in the field such as water situation, density of weeds, presence of other pests and natural enemies seen but not found in the sample plant. c. After the small group analysis, their recommendation for the week can be written.
10. Now discuss the questions relevant for the growth stage of the cotton crop observed.
11. Each group should present their agroecosystem analysis to the complete FFS group.
12. A final group decision is made on how to manage the Farmers Practice and IPM FFS plots in the following week, based on discussion of the 7 steps in the table below.
Annexes (II)
179
Summary table of AESA observations, discussion questions and type of actions to consider for crop management or FFS learning
Steps
What to observe
What to ask - discuss
Actions
1
Weather
Rainy? Dry?
1. Do we need to water?
Trends in weather
2. Preparation of beds?
Dry/wet season
3. Disease management?
Effects on crop 2
Crop condition
Age of crop:
1. Needs fertilizer?
Seedling
2. Needs watering?
Veg. growth
3. Fungicides?
Flowering
4. Special topic?
Fruiting Colour of leaves Leafspots? Diseases?
3
Field condition
Soil structure:
1. Hand weeding?
Hard?
2. Soil aeration?
Wet?
Annexes (II)
Weeds present?
4
Herbivores
What herbivores?
1. Carry out an ‘insect zoo’ exercise to understand pest life cycle
Population? 2. Special topic Are they damaging?
5
Natural enemies (and
What NE? Population?
1. Insect zoo 2. Special topic
neutrals)
6
Activities in
Do neighbours spray?
180
Compare with FFS Farmers’
Example of cotton growth stage specific questions to discuss during AESA Growth stage: 39 - 45 days after seeding 1. What was the effect of last week's decision? 2. Describe plant development (height, leaf length, number of branches, number of leaves, buds)? Describe root development? 3. What kind of nutrient does the plant need in this stage?
4. What is the difference between composition and density of pests and natural enemies in the Farmers Practice and IPM plots? Which of these is important? 5. What natural enemies did you see in the field? What is the role of natural enemies in the ecosystem? 6. Describe the weather condition (hot sunny, dry cold, wet cold, etc.). Is the soil wet enough? How does it influence plant growth and development? How does it influence diseases? 7. What is your management decision for this week? Compare this with farmersâ&#x20AC;&#x2122; decisions locally.
Annexes (II)
181
Source of Information Field Guide Exercises for IPM in Cotton. Vietnam IPM National Programme (2000). Downloadable via: http://www.vegetableipmasia.org/uploads/files/document/ TrainingMaterials/IPM_Cotton.pdf
Annexes (II)
Cotton Ecosystem Analysis chart from Ethiopia FFS training session
182
Photo from the FAO FFS trainers guide for Integrated Pest and Production Management in cotton. Gestion intégrée de la production et des déprédateurs du coton. Guide du facilitateur pour les Champs écoles des producteurs. FAO, 2014. Credit: William Settle
Annexes (II)
183
Annex III
Annexes (III)
(a) Beneficial insect assessment sheet
184
3
2
1
8
7
6
5
4
3
2
1
8
7
6
5
4
3
2
1
No
No
1
Plant
Rep
.......
Egg
Larva
Ladybird beetles
Adult
Spider
Ants
Egg
Larva
Green lacewing (Chrysopa)
Syrphid Fly
Asian Bugs
Praying mantids
Parasit oids
Others
Remark
Signature…………………………...….
Data Collectors Name………………………………………. Date……………..……………………….
Adult
Hoverfly (Larva)
Treatment No………………. Date ………… Time Start ……..…… Time End …………… Weather….......…….. Location…...............…..
Annexes (III)
185
Annex III
Annexes (III)
(b) Pest assessment sheet
186
1
1
2
No
No
8
7
6
5
4
3
2
1
8
7
6
5
4
3
2
Plant
Rep
Egg
Small Larva
African bollworm
Larva
Big
Egg
Beetle
Aphid Flea Fly
Jassid White
Thrips
Cottony cushion scale
Stainer bugs
Cotton Leaf Worm
Bugs Spider Mites
Signature……………………………….
Date……………………………………………
Data Collectors Name……………………………………….
Larva
Pink BW
Larva Egg
Spiny BW
Treatment No………………. Date ………… Time Start ………… Time End …………… Weather………………….. Location………….………..
Annexes (III)
187
Remark
List of acronyms ACRI
Australian Cotton Research Institute
BFP
Benin Food Product (dried, powdered maize ingredient for one food spray recipe)
BoA
Board of Agriculture
B.t.
Bacillus thuringiensis (bacterial toxin in genetically modified B.t. cotton varieties)
EC
Emulsifiable concentrate (type of pesticide formulation)
ETB
Ethiopian birr (currency)
FAO
Food & Agriculture Organisation of the United Nations
FFS
Farmer Field School
HHP
Highly Hazardous Pesticide
IPM
Integrated Pest Management
ISD
Institute for Sustainable Development
NGO
Non-governmental organisation
OBEPAB
Benin Organisation for Promotion of Organic Agriculture
PAN
Pesticide Action Network
PPE
Personal Protective Equipment
ULV
Ultra Low Volume (type of pesticide application method)
UNEP
United Nations Environment Programme
188
189
www.pan-uk.org