COTTON WITHOUT HIGHLY HAZARDOUS PESTICIDES Ethiopian experiences in growing high quality, high yield cotton using agroecological methods Background Cotton is grown by smallholder farmers and large commercial farms in Ethiopia’s southern Rift Valley. Production can be challenging as the crop is prone to attack by a wide variety of pests, especially African bollworm Helicoverpa armigera and sucking pests like whiteflies and aphids. Farmers have to manage these and other pests effectively to gain decent yield and profit from their cotton and most have relied on the use of synthetic pesticides for pest control. Cotton farms mainly use older organophosphate, organochlorine and carbamate insecticides, many of which qualify as Highly Hazardous Pesticides (HHPs), including endosulfan, malathion, carbosulfan, dimethoate and dicofol (Table 1). Endosulfan is a Persistent Organic Pollutant (POP) listed for global banning under the Stockholm Convention since 2011, yet remains widely in use by cotton farms. Large cotton farms may apply these hazardous insecticides up to 5 times per season, depending on pest incidence, by motorised or manual spray kit. A few years ago, aerial application was common, posing very high risk of drift to non-target areas. Smallholder farmers usually made several insecticide applications by knapsack sprayer until 2012-13 when falling cotton prices made agrochemical inputs less affordable for many, although some continue to spray their cotton. While there is no concrete data on health effects linked to HHP exposure in cotton, survey information from farm workers and smallholders indicates that pesticide poisoning incidents were common, particularly for workers exposed during aerial spraying. Workers who applied pesticides were not using protective clothes, greatly increasing their poisoning risk. Lack of proper protective equipment, workers’ and farmers’ perceptions of pesticides as ‘plant medicines’ (rather than ‘poisons’) and the hot climate in the Rift Valley were among the reasons for increased pesticide exposure and poisoning
Applying food spray to cotton foliage to attract predatory insects. Credit: PAN Ethiopia incidents. Beekeeping is an important source of income for many farm families and farmers reported bee kills, loss of hives and reduced honey production in areas near aerial spraying, compounding stresses on pollinator populations from deforestation. The negative impacts of HHPs on human and environmental health raise concerns over the nonsustainability of long-term reliance on pesticides. Risks to health and biodiversity are aggravated by cotton farmers’ limited knowledge on responsible use of pesticides and lack of appropriate and easily accessible alternatives. This leaflet summarises recent success with alternative cotton pest management options, including an innovative ‘food spray’ method to attract beneficial insects into cotton fields to enhance natural, biological control. The method has been trialled in the Arba Minch area and has grabbed the attention of cotton farmers and government departments.
Table 1. HHP hazard qualifications* for insecticides used in cotton in southern Ethiopia Active ingredient
International Conventions
HHP: Acute toxicity to human health
carbosulfan
recommended for PIC listing by Rotterdam Chemical Review Committee
Fatal by inhalation
dicofol
under risk evaluation for Stockholm POP listing
HHP: Chronic human health hazard
Highly toxic to bees
dimethoate endosulfan malathion
HHP: Environmental hazard
Highly toxic to bees Stockholm POP Listed Rotterdam PIC Listed
Fatal by inhalation
Highly toxic to bees Probable carcinogen
Highly toxic to bees
*As per PAN International List of HHPs version Dec. 2016. Available via: http://www.pan-uk.org/highly-hazardous-pesticides/ PIC = Prior Informed Consent of Rotterdam Convention
The food spray method: an innovative way to enhance biological pest control in cotton A pest management system that does not rely solely on chemical control is needed to reduce Ethiopian cotton farmers’ dependence on synthetic pesticides. In cotton, naturally occurring beneficial invertebrates, notably predatory insects, such as ladybird beetles, can be very effective in keeping pests in check. These natural enemies prey on soft-bodied insects, pest eggs and small bollworm larvae. If natural enemies can be brought into cotton fields early in the season, so that they are ‘ready and waiting’ before the major pests arrive, they can help keep pest populations from reaching economically damaging levels and enable farmers to reduce pesticide applications. In fact, avoiding broad-spectrum insecticides as much as possible is an essential component of the food spray method as predatory insects are very easily killed by HHPs. The ‘food spray’ method was first developed for large scale cotton production by Dr Robert Mensah at the Australian Cotton Research Institute. In collaboration with PAN UK and local NGO, OBEPAB, the method was adapted for resource-poor smallholders in Benin, West Africa, to complement their organic practices. It was found to be effective in terms of enhancing biological pest management and increasing yield and net profits for Beninese farmers1. The food spray can be prepared cheaply by farmers from local materials. One ‘recipe’ uses brewer’s yeast, which can be obtained as a waste product from breweries. Another uses coarsely ground and soaked maize, which is then dried into powder. A solution is made diluting the food spray solids and filtering these out before adding the solution to the spray tank to apply to cotton foliage. The odour from the food spray attracts predatory insects into the crop as it mimics the smell released by their prey. Research2 shows that applying food sprays can shift the ecological balance to favour the natural enemies over the pests and increases predator searching ability and prey consumption rate. Farmers need to learn how to check this balance in their fields, doing simple counts of predator and pests every few days to observe when a further food spray may be needed.
Testing the food spray method in Ethiopia
Improved yield and farmer income
As part of a farmer training project for sustainable cotton, Pesticide Action Nexus Ethiopia, in partnership with the Arba Minch Plant Health Clinic and extension staff from the regional Board of Agriculture, has been trialling the food spray method in the southern Rift Valley of Ethiopia since 2013, in smallholder and large farms.
Higher seed cotton yields and profits were recorded in almost all the food spray treated plots compared to farmers’ current practices (whether insecticide treated or, in the case of many smallholders, with no pesticide inputs and little effort to manage pests). In the smallholder context, yield and economic comparison in nine different villages consistently found that food spray treatment in an IPM system with certified seed was more profitable than practices of untrained farmers, whether these used pesticides or not. Table 2 gives examples from two FFS demonstration sites.
Both the maize-based Benin food spray product and the brewers’ yeast recipe were tested and in combination with powdered neem seeds (Azadirachta indica) and compared with untreated cotton and standard insecticide treatments. Trials were conducted in different agroecological zones of Arba Minch Zuria and Merab Abaya districts in Gamo Gofa zone, as part of IPM demonstrations for Farmer Field School training with smallholders and as IPM research plots on two large farms. The trial plots included borders of two or three rows of maize sown as a trap crop for egg-laying bollworm moths and as habitat refuge for natural enemies. This habitat management forms another component of the food spray method. The maize borders also help reduce insecticide drift from treated to nontreated experimental plots. Over four consecutive seasons the trials clearly showed that natural enemies responded to food spray application and played an effective role in cotton pest management. Weekly field counts of pests and beneficials revealed increased in-crop diversity of insects in the food spray treated plots compared to the untreated and chemical treated plots. Significantly higher numbers of beneficial insects were recorded in the food spray treated plots, while insecticide applications often led to decreases. The research concluded3 that food sprays do work to attract natural enemies in the Ethiopian context and the food spray method could form the basis for alternative pest management strategies in smallholder fields and on large farms.
Data from the experimental plots in the two large farms in 2014 and 2015 indicated that there was no significant difference between the yield obtained from chemical treated and food spray treated plots but the net profit obtained from the food spray treated plots was higher as costs for preparing the food spray were lower than using insecticides. The environmental and human health benefits of not spraying HHPs are another advantage of ecological pest management strategies, ignored in standard economic analysis. In one season, on one of the large farms, food spray treatment delivered slightly lower but broadly similar yield and net revenue to the farm’s standard insecticide regime as carried out in the IPM trial area, where project staff supervised all agronomic tasks and the same certified seed was used as in the food spray plots. However, food sprayed and even untreated plots in the IPM trial area yielded much better than the main fields on the large farm, which were not well managed, lacked good field sanitation to remove bollworm breeding sites and used poor quality seed. These results highlight the importance of good cultural practices- an essential component of effective Integrated Pest Management- as well as the technical and economic benefits of enhanced biological control.
Farmers discuss cotton plant health in trials of food spray treatments. Credit: PAN Ethiopia The FFS approach in which farmers learn to analyse the cotton agroecosystem is one factor for success. The seasonlong curriculum includes: • proper land preparation and using high quality seed • row sowing at appropriate spacing • insect scouting and identification skills for major pests and beneficial insects • preparation and application of food spray and decision making on when to apply • careful and timely weeding and irrigation • cleaning crop waste after harvest to prevent pest carry-over
Table 2. Yield and economic impacts of cotton crops managed with food spray and insecticides at Genta Kanchama and Kolla Mulato Farmer Field School sites in 2015 production season (costs in Ethiopian birr ETB and seed cotton price 15ETB per kg) Farm
Treatments
Seed cotton yield (kg/ha)
Total revenue from Total production seed cotton cost
Net revenue
Genta Kanchama
Food spray
4,385
65,775
9,650
56,126
Conventional / Insecticide
1,497
22,460
4,832
17,627
Untreated
3,262
48,930
7,324
41,606
Food spray
2,380
35,696
5,688
30,007
Conventional / Insecticide
1,497
22,460
4,567
17,893
Untreated
1,979
29,679
4,757
24,922
Kolla Mulato
US$ = 21 ETB Dec. 2015 Insecticide treatment: Malathion 50% EC at 2 litres/ha x 3 applications (G Kanchama) and x 1 application (K Mulato)
Farmer training in IPM and uptake of the food spray method Impact surveys show that smallholders completing a full season of FFS training and taking up the food spray method and good cultural practices typically achieve yields 50-100% higher than non-trained farmers. Only 3% of FFS graduates reported using pesticides and 63% said they made use of food sprays. FFS farmers in Shelle Mella have set up an organic cotton growers’ cooperative to gain better prices and markets and their lint quality has been graded Class A since 2015. The project has now trained more than 2000 farmers in nine villages, field staff from two large farms and 34 government extension agents. A trainers’ guide to using the food spray method has been produced4 and an IPM toolkit for Ethiopian cotton is underway. Development of organic cotton production could bring many benefits to Ethiopia’s cotton farmers, including improved soil fertility, protection of human and environmental health, maintained productivity and health of the work force. Given the premium prices commanded by good quality cotton in the national market and organic cotton in global markets, there is huge potential for improved livelihoods for poor farming households in growing ecological cotton.
Scouting for pests and predator insects in young cotton rows. Credit - PAN Ethiopia
References: Benin: productive and profitable organic cotton. S Williamson & DS Vodouhê, Chapter 7.1 in: Replacing Chemicals with Biology: Phasing out highly hazardous pesticides with agroecology. Pesticide Action Network International, 2015. Via: http://pan-international.org/resources/ 1
Mensah RK, Vodouhe DS, Sanfillippo D, Assogbab G, Monday P. 2012. Increasing organic cotton production in Benin West Africa with a supplementary food spray product to manage pests and beneficial insects. Int J Pest Manag. 58: 53–64 2
Amera, T, Mensah, RK & Belay, A. (2017) 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, DOI:10.1080/09670874.2016.1278084. 3
Using the Food Spray Method to enhance biological control in cotton: a trainers’ guide. PAN UK, 2016. http://www.pan-uk.org/manuals-guides/
For more information: Atalo Belay, Project Coordinator, Pesticide Action Nexus Ethiopia. Email: feelatalo@gmail.com Stephanie Williamson, Staff Scientist, PAN UK. Email: Stephanie@pan-uk.org Read about PAN UK’s cotton programmes in Ethiopia and Benin via http://www.pan-uk.org/cotton/
Pesticide Action Network, UK The Brighthelm Centre, North Road, Brighton, BN1 1YD www.pan-uk.org
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April 2017
The IPM work on cotton in Ethiopia is kindly funded by the JJ Charitable Trust and by TRAID