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OUTGROWING PROJECT

HAZELNUT PROTECTION GUIDELINE

This document is intended to be a user friendly operational guide addressed to the hazelnut growers. Ferrero Group waives any responsibility in respect to the completeness and accuracy of the content of this operational guide which in no case is to be considered as a binding document for the hazelnut growers.

This publication was made possible through support provided by the U.S. Agency for International Development, under the terms of Contract No. 72011219C00001. The opinions expressed herein are those of the author and do not necessarily reflect the views of the U.S. Agency for International Development.

INDEX Diseases and pests of hazelnut Insects and mites

Big bud mite - Phytoptus avellaneae

Hazelnut weevil - Curculio nucum

7 8 8

12 Common stink bugs - Gonocerus acuteangulatus, Palomena prasina i Nezara viridula 15 Brown marmorated stink bug - BMSB Halyomorpha halys 19

Hazelnut and Walnut Twig Borer - Oberea linearis

Hazelnut aphid - Myzocallis coryli

Hazelnut scale - Eulecanium coryli

Beech splendor beetle - Agrilus viridis

Fungal diseases

31 34

Anthracnose - Piggotia coryli

Powdery mildew - Phyllactinia guttata i Erysiphe corylacearum

Cytospora canker - Cytospora corylicola

Hazelnut brown rot - Monilia coryli

Bacterial diseases

Bacterial canker - Pseudomonas avellanae

Bacterial blight - Xanthomonas arboricola pv corylina Virus diseases

Apple mosaic virus - ApMV Physiological disorders

Brown stains

Damage caused by extreme weather conditions Frost, Hail, Waterlogging

Good production practice

46 46 50 54 54 57 57

61 62

Treatment technology

Health and safety at work

Calendar of hazelnut protection

Protection of productive plantations

Protection of young plantations

INTRODUCTION

Protection of hazelnuts from diseases and pests is one of the indispensable agronomic measures. Proper and timely protection ensures unhindered growth and development of hazelnuts and production of quality hazelnuts that meet the quality standards. This booklet was developed as a practical tool for growers and technicians to aid identification of main pests and diseases that might occur in hazelnut orchards as well as to gain practical understanding of orchard management and crop protection. For each pest and disease presented, most common symptoms, life cycle and biology, and means of control are shortly described. Prof. Dr. Luciana Tavella and Dr. Marco Scortichini made an expert contribution to the development of this handbook. For what concerns chemical control measures, authorized plant protection products and their conditions of use might change over time. Therefore, information provided in this booklet should be considered as a general indication only. The indications in the label of each product must always be followed in order to perform the application correctly.

DISEASES AND PESTS OF HAZELNUT

BIG BUD MITE Scientific name: Phytoptus avellaneae Symptoms: Appearance of large and deformed buds, evident from winter and increasing in early spring

PEST DESCRIPTION The Big Bud Mite (Phytoptus avellaneae) is a common pest present in most of the area of cultivation of hazelnuts, especially in Europe, Turkey and Georgia. These mites colonize the buds, where they feed, injecting their saliva. The result is the deformation of the host buds, due to the reaction of the plant to the trophic activity of the mites. The affected buds will be unable to produce healthy new sprouts, with consequent reduction of production capacity. Pest susceptibility may vary considerably depending on hazelnut varieties. On sensitive varieties, in absence of control, damages up to 70% have been recorded. The economic threshold for treatments is usually set at 10% of buds infested for young plantations and 15% of buds infested in productive plantations.

Infested hazelnut buds ©SAGEA

PEST CYCLE & BIOLOGY In spring, the young forms (vagrant form) of the mite emerge from the affected buds and move along the stem to colonize new buds. The migration takes place with daily temperatures of 15-20 °C, often occurring when the trees open the third/fourth leaf. The migration phase can last up to a month. The mites remain hidden in the narrow space at the base of the bud, until the bud develops sufficiently that the outer leaf scale slightly lifted, allowing the mites to enter. Once inside the new bud they become adults and start reproduction (gall form), with the peak of activity at the end of the following winter, causing the deformation of the host bud and start migration to a new bud. Swollen, infested buds ©SAGEA

Infested hazelnut buds ©Dr. Darko Jevremović, Fruit Research Institute Čačak

10 PUPOLJAK NAPADNUT GRINJAMA

NORMALNA VELIČINA PUPOLJKA

MEANS OF CONTROL The control of the pest can be done mechanically or using agrochemicals.

Mechanical control The mechanical control can done picking the damaged buds during winter and early spring, before their opening and consequent migration of mites to new buds. The material removed should be taken away from the orchard or burned. PROS: very selective and environmental secure control strategy. CONS: time-consuming activity and difficult to be performed in large orchards, on tall trees and with high level of infestation, for the large number of buds to be removed.

Chemical control Chemicals can be applied when the vagrant form is present, during the migration to the new buds. This normally starts when the plant has opened the 2nd-3rd leaf. Migration is a continuous process, lasting some weeks (end of winterbeginning of spring), and influenced by:

• phenological phase of the plant • temperature (necessary 15-20 °C during the day) However, the monitoring is mandatory to individuate the correct timing of treatment and can be done observing the vagrant form in the proximity of the big buds, with a magnifying lens. Treatments can be done with registered sulfur based products or acaricides, following the indications present in the labels. RIGHT MOMENT FOR SPRAY APPLICATION!

TOO LATE!

TOO LATE FOR SPRAY APPLICATION!

Infested hazelnut buds ©Dr.Darko Jevremović, Fruit Research Institute Čačak

NUT WEEVIL Scientific name: Curculio nucum Symptoms: Early drop of immature nuts caused by adult feeding, a round hole on a nutshell made by emerging larvae

PEST DESCRIPTION The Nut Weevil (Curculio nucum) is considered the most important pest affecting hazelnuts in most of the hazelnut growing countries. Adults are present in the orchard from spring to the end of August. Adults damage the crop by feeding on buds. Using the same snout-like structure, females pierce maturing nut to create a hole in the shell for placing the egg. The most important nut weevil damage is by larval feeding on kernels and their development inside the nuts. The pest is known to cause up to 80% of yield loss, especially in orchards located closer to the woods. The most common hazelnut varieties are susceptible to nut weevil; however, varieties that lignify the shell more rapidly (e.g. Tonda Gentile delle Langhe) are less subjected to damage by this pest.

Damage made by feeding and developing inside the nutshell ©Dr. Darko Jevremović, Fruit Research Institute Čačak

Nut weevil adult on a hazelnut leaf ©entomart

PEST CYCLE & BIOLOGY Nut weevil completes one generation a year or 2-3 years. Adults usually emerge from the soil in spring at the beginning of May. Mating occurs approximately in a month time (end of May). Females usually start oviposition (a single egg per nut) when the mean temperatures exceed 18 °C and each female can lay 30‐40 white, yellowish eggs. It takes from 5 to 7 days for the larvae to hatch from the egg. Larvae feed on the kernel and develops inside the nut during 30 days. After this period, mature larvae leave the nut and enter the soil leaving a round hole on the nutshell, which represents the typical pest symptom. Larvae burrow in the soil 10-15 cm deep where they overwinter until the following spring.

Damage made by feeding and developing inside the nutshell ©SAGEA

Round holes made by exiting nut weevil larvae ©SAGEA

MEANS OF CONTROL The control of the pest is mechanical or by using insecticides.

Mechanical control Mechanical means could be used to reduce the number of larvae in the soil. Soil tillage in the area around the trees is recommended in early spring (beginning of April) while larvae and pupae are still burried in the soil at 10-15 cm deep. Collection of damaged, fallen fruits and their removal from the orchard also help in reducing the population size. PROS: environmentally secure control strategy, contributes to reduce pest abundance as suplement to chemical treatment. CONS: time-consuming and difficult to be performed in large orchards.

Chemical control Chemicals can be applied only when adults start to be active invading the orchard and before females lay eggs. This normally happens at the beginning of May, when the fruits are young and green. Frappage monitoring technique allows identification of treatment timing. The threshold for conducting the treatment is 1-2 females with mature eggs per plant. Currently registered insecticides, allowed for use against nut weevil, are:

• Lambda-cyhalothrin The indications on the label of each product must always be followed in order to perform the application correctly. Correct timing for chemical treatments of adults (2 individuals /plant) when the formed fruits are in green color .

Soil tillage should be performed in the area around trees for control of larvae, 10-15 cm deep ©SAGEA

COMMON STINK BUGS Scientific name: Gonocerus acuteangulatus , Palomena prasina , Nezara viridula Symptoms: Early nut drop and seed abortion due to early attacks; corking damage, dark spots on seed due to attacks during kernel growth

PEST DESCRIPTION Gonocerus acuteangulatus, Nezara viridula and Palomena prasina are the common bug species, often found together in hazelnut-cropping areas. Species composition and abundance change in relation to the geographic area. All species can feed on lignified nuts damaging the kernel until harvest. Feeing during shell expansion can increase seed abortion and early nut drop, while feeding during kernel growth determines alterations evident on seed, also indicated as ‘corking’, consisting of whitish to black spots on kernel.

Gonocerus acuteangulatus

• Is polyphagous (range includes trees and bushes), and a very good flier. • Females lay single yellow golden eggs on both leaf sides.

Gonocerus acuteangulatus, odrasla jedinka (levo) i larva (desno) ©Zoran Gavrilović

Nezara viridula

• Has a wide host range, with preference for herbaceous plants. • Females lay eggs on leaf underside in masses of on average 70 eggs.

2mm

5mm

10mm

Nezara viridula, 2nd, 3rd, 4th and 5th young stages and adult green with three yellow spots on the scutellum ©Plant & Food Research, New Zealand

Palomena prasina

• Has a wide host range, with preference for trees and bushes. • Females lay eggs on leaf underside in masses of about 28 eggs.

Palomena prasina development stages ©Ian Tew, © Zoran Gavrilović

PEST CYCLE & BIOLOGY Adults appear in hazelnut orchards in mid-April. They can move to and from other plants throughout the season, causing continuous recolonization. They start leaving hazelnut orchards after harvest at the end of summer, in search of wintering sites.

Gonocerus acuteangulatus

• Completes 1 generation per year, overwintering as adult. • All nymphal instars live and develop on hazelnut, generally in June-July i jula Nezara viridula completes 2 generations per year, overwintering as adult in different shelters (underneath • Usually tree corks, woods, buildings).

Palomena prasina

• Completes 1 generation per year, overwintering as adult. • First nymphal instars generally prefer to live and develop on herbaceous plants.

Common stink bug nymphs in green. ©SAGEA

Damage caused by late stinkbug attack. Attacks in early fruit development induce seed abortion and early nut drop. ©SAGEA

MEANS OF CONTROL Monitoring Beat sheet sampling (or frappage) allows identification of treatment timing. out in the early morning 4.00 – 6.00 am. • Carry Place white, plastic sheets between rows (5 plants long). • For a representative monitor in several points in the orchard. • Collect insects from sample, the sheets in a plastic bag for count and identification. •

Chemical control Difficulties: persistence of the products • Short currently in use. insect capacity to avoid • Great treatments flying on the nearby fields and recolonize hazelnut orchard after few days.

Agronomical aspects: with the first appearance • React of insects in the orchards, when

2 individuals/plant are found (any species), and hazelnut is susceptible to their feeding punctures.

out a correct execution of • Carry treatments, covering the entire foliage

and performing treatments in the evening or night hours.

treatments, before insect • Preventative appearance and hazelnut susceptibility are useless.

BROWN MARMORATED STINK BUG - BMSB Scientific name: Halyomorpha halys Symptoms: Eggs in cluster on the leaf underside, empty nutshells, shriveled kernel, corking damage on kernel

PEST DESCRIPTION Brown marmorated stink bug (BMSB) is a damaging invasive pest responsible for severe economic damage to a wide range of high-value specialty crops including hazelnuts. BMSB is well established in commercial hazelnut areas of Turkey, Italy, Georgia and USA. BMSB attacks hazelnuts in all development stages, from fruit set to harvest. Adults and nymphs feed by sucking plant sap from all vegetative parts. Damage occurs when insects insert their mouthpart through the nut shell and feed on hazelnut kernel. Injuries result in fruit deformations. Feeding during fruit set prevents kernel formation producing blank, empty shells. In later phenological stages feeding causes malformed kernels or corking (insect feeds on mature kernel). Hazelnut shell thickness and hardness do not prevent BMSB from feeding. Most of the commercial varieties are susceptible to BMSB.

Brown Marmorated Stink Bug, 13-17 mm long, shieldshaped, brown, resembling marbel ©Birgit Rhode, Manaaki Whenua ‐ Landcare Research, New Zealand

BMSB on hazelnut ©SAGEA

PEST CYCLE & BIOLOGY With a very high reproductive rate, BMSB has mostly 2 generations in Europe and 4-6 in Asia. It overwinters as adults which leave the winter refuges in late March-April when the temperature exceeds 14°C. After overwintering and a long period of nutrition, first mating occurs in May (approx. 21°C). Eggs are laid on the leaf underside in masses of 28 eggs from mid-May to mid-August. First instar nymphs stay on egg mass, while from the next instars they actively move and feed. From the end of autumn season, adults can be found in urban areas aggregating in large groups in houses and buildings.

BMSB searches dry and protected shelters to overwinter. You can easily recognize the egg masses according to the number and disposal of the eggs.

BMSB eggs, first instar nymphs (2-3 mm) on the underside, later instar nymphs feeding on hazelnuts and adult on maturing nut ©SAGEA

MEANS OF CONTROL Chemical control Difficulties: is difficult due to adults’ constant movement to and from uncultivated areas. • Monitoring moves quickly between crops which allows the insect to escape applications and recover in • BMSB untreated areas. occur also very close to harvest. • Attacks In Serbia are no registered insecticides for use against BMSB on hazelnut crop. • In general,there very few products are available on hazelnut compared to other crops. • Considerations: periods - pre-harvest and between the first and the second harvest. • Critical Adults of generation are less susceptible to sprays than those of winter generation. • Due to thesummer frequent movement between crops, insects are more abundant on the edges. • Agronomical aspects: a better efficacy of the treatments, applications should be performed in the early morning when • For the insects are less active. good penetration of spray applications inside the canopy. • Ensure Well-pruned hazelnut trees are easier to protect than unpruned ones. •

Conduct monitoring in these 2 phenological stages – when fertilized ovary is visible and when it enlarges to form the nut ©Agrion

HAZELNUT AND WALNUT TWIG BORER - HWTB Scientific name: Oberea linearis Symptoms: Necrotic tissue as a sign of egg-laying spot, dried branches

PEST DESCRIPTION Hazelnut and Walnut Twig Borer (HWTB) is a wood-boring insect. Adults are black with long antennae and yellow legs, 11-16 mm long and slender. In hazelnut orchards they appear in spring. Larvae are yellow and brown, without legs. During the month of June, dry leaves might be noticed. Important to distinguish natural twig drying-up and the harm caused by the pest. Injured shoots turn brown and the tissues around the eggs become necrotic due to the presence of egg-laying scars.

Oberea linearis adult ©Otto Bylén Claesson

Larva in a gallery in a hazelnut twig ©Dr Rade Miletić

On the first picture, egg laying scar, necrotic tissue, and the gallery ©Loru L., Marras P. M. & Pantaleoni R. A., 2007 [2008]

PEST CYCLE & BIOLOGY In most of Europe, HWTB completes one generation in 2 years, whereas in areas with colder climate life cycle might take 3 years. Underneath the bark of twigs, 10-15 cm from the tip, females make thiny slit for placing the eggs. Newly hatched larvae bore circular galleries in hazelnut twigs, and consequently the apical part of the shoot wilts and breaks off. The long gallery (40-60 cm the first year) goes towards the base of the shoot. In autumn, larvae enter diapause until the following spring when they start again boring galleries. Larvae do not leave the gallery in which they continue their development. After diapause in the second winter, mature larvae pupate in April, and new adults emerge in May-June. The consequence of existing galleries is drying up and spltting of shoots.

Adult taking flight ©Otto Bylén Claesson

Mature larva 20-25 mm long ©Zdeněk Hromádko

Mesto ubušivanja u granu leske, Agriser

Dried branch due to larval galleries ©Loru L., Marras P. M. & Pantaleoni R. A., 2007 [2008]

MEANS OF CONTROL Pest biology does not leave many management options for farmers. In Serbia, mechanical control in the form of pruning and burning of the attacked shoots has proven to be very effective. Mechanical control should be done adults emerge, from late autumn to early spring • Before Infested dry twigs should be cut at the base, removed from the orchard and destroyed • Chemical measure relies on spraying contact insecticide with long residual action in spring when adults emerge. Currently there are no registered insecticides on hazelnut in Serbia. In Turkey, products based on methiocarb are in use.

Gallery

Dried out part with brown coloration as a consequence of galleries. When pruning, this branch should be cut at the base ©SAGEA

HAZELNUT APHID Scientific name: Myzocallis coryli Symptoms: Honeydew (i.e., sticky sugar substance) on the foliage, colonies of numerous insects on the leaf underside, less vigorous leaves

PEST DESCRIPTION Filbert aphid Myzocallis coryli is a common pest in hazelnut-cultivating areas of Europe, Turkey, Southwest Asia, North and South America, Australia and New Zealand. Adults are light to dark green and approximately 2.5 mm long, while nymphs are yellowish white with long hairs. Eggs are black, and present only in winter (winter stage). Filbert aphid sucks plant sap preferably from young leaves, which then turn dry, yellow and eventually drop. In case of severe infestation with numerous large colonies, it reduces tree vigour and nut size leaving often empty shells. Indirect damage is related to honeydew, sticky substance that aphids excrete and drops to the foliage. Honeydew is a sugar-rich substance and represents a good substrate for fungal growth (e.g., sooty mold) especially in mid-summer and autumn.

Myzocallis coryli ©influentialpoints.com

Winged adult of Myzocallis coryli ©influentialpoints.com

First generation aphids (oviparae) are whitish, pale orange or yellow ©influentialpoints.com

Leaf of European hazel with honeydew of aphid and sooty mold ©Alfonso Aguilera Puente

PEST CYCLE & BIOLOGY Pest overwinters as eggs laid on branches, often near buds, in autumn. In early spring, newly hatched nymphs initially feed on swelling buds; then, when the leaves start to unfold, they continue feeding on their undersides. Due to cold temperatures, nymphs take 2, 3 or more weeks to become winged females (in late April-early May). These females, called fundatrices, are parthenogenetic and give birth to other parthenogenetic females (viviparae) along the season. The population reaches its maximum usually in June-early July. During summer, aphids feed on leaves underside, stems and maturing nuts. In autumn, winged females produce the offspring capable of laying eggs again. summer, it completes 6 to 8 generations. • During temperature for M. coryli development is estimated at 3.2 ºC. • Min When • the temperatures are high (July, August), population drops down.

6 TO 8 GENERATIONS, THE LAST ONE PRODUCES EGGS THAT OVERWINTER

Eggs are positioned around the buds @ influentialpoints.com

Adult giving birth to vivipare ©influentialpoints.com

Oviparae, young hatched from eggs ©influentialpoints.com

Vivipare, young born without egg ©influentialpoints.com

MEANS OF CONTROL In hazelnut orchard, insecticides are the most common method to control aphids. A proper monitoring through all spring and summer months should ensure better control and reduction in chemical applications.

Visual inspection: three terminal branches per tree • checking leaves per terminal branch • three • counting the number of aphids per leaf

Chemical control: Applications should be done at formation of first colonies and in the absence of natural enemies. In fact, aphid predators and parasitoids are very abundant in the hazelnut orchard, and they are often able to control effectively the filbert aphid infestations, without any insecticide applications. Products approved for the use in hazelnut orchard against aphids in Serbia are based on paraffinic mineral oil, deltamethrin, and acetamiprid. The indications present in the label of each product must always be followed in order to perform the application correctly.

HAZELNUT LECANIUM SCALE Scientific name: Eulecanium coryli sinonim Eulecanium tiliae Symptoms: Honeydew, adult insects grouped on the twigs

PEST DESCRIPTION Widely distributed in Europe, hazelnut scale is a common pest of ornamental trees and shrubs. However, it attacks hazelnuts and various fruit trees. The female (5- 6 mm long), from dark chestnut-brown to light brown, oval and strongly convex in shape, after the oviposition becomes flatten and rugged. The insect produces abundant honeydew. In Italy the pest is known as „Cocciniglia or lecanio del nocciolo“ which sporadically occurs in hazelnut orchards in Piedmont region, generally as a consequence of repeated and intensive use of broadspectrum insecticides, which are toxic to its natural enemies.

Infested hazelnut twigs and females in active oviposition ©Agrion

Eulecanium tiliae ©Hans Jonkman (Plant Parasites of Europe)

PEST CYCLE & BIOLOGY Hazelnut scale completes a single generation per year. Pest overwinters as nymphs mostly on the buds but also on the shoots. In spring, nymphs migrate to the developing buds. This event is dependent on bud development and therefore climate conditions. Later, usually in May, sexually mature females, after mating, lay eggs. Eggs remain protected by the female’ bodies until they hatch. Hatching usually occurs towards the end of the summer. First nymphs crawl and explore the host plant until they settle down. Eventually, they reach a leaf underside where they feed and remain fixed until the beginning of the autumn.

Eulecanium tiliae proizvodi mednu rosu, Fruška gora, Iriški venac, 2011 ©Dragiša Savić

Eulecanium tiliae ©Hans Jonkman (Plant Parasites of Europe)

MEANS OF CONTROL The threshold at which it is neccessary to interact against hazelnut scale is very low (just few females per meter of wooden area). According to experiments effected in the recent years, crop protection against hazelnut scale should be performed in two distinct vegetative stages: in spring, when the buds break, and in autumn, when leaves naturally start to fall. In both timings, it is recommended to use mineral oil with following instructions: not apply treatments when the temperature is below 5°C or when rain or humidity higher than • Do 90% are forecasted within 36 to 48 hours after the application. must be done within the hours when the vegetation is dry. • Application oil performs to its fullest only if the application covers completely the infested area and the • Mineral insects. When hazelnut scale is covered with the oil, its respiratory system collapses and the insect dies due to suffocation.

ensure the wooden hazelnut area is fully covered, it is recommended to spray the same row in • To both directions.

Eulecanium tiliae ©Peter Smith, 2019

BEECH SPLENDOR BEETLE Scientific name: Agrilus viridis Symptoms: Drying of the apical part of the canopy, reduced overall plant vigour, serpentine tunnels when the bark is removed

PEST DESCRIPTION Native to Europe, beech splendor beetle commonly lives on beech trees. In the recent years, in Italy it was recorded to be particularly dangerous for hazelnut trees as well. The beetle infests the hazel orchard usually from mid-May to October. Eggs are deposited in masses on the tree bark and up to 24 per mass. Larvae dig deep galleries in woody tissues of trunk and branches, which cause the branches to dry. Affected hazel trees are recognised by chlorotic appearance and reduced vigour. During summer, the canopies might turn yellow and in case of heavy attacks they might completely dry up. An increase in beetle population and outbreaks occur when the plants are weakened or stressed by extended drought.

Hazelnut trees attacked by larvae, dry up from the apical part up to the damaged zone ©Agrion Female, metalic to olive green and 5-11 mm long, lays batches of eggs on the bark of the trunk and branches ©R. Petercord

Swellings on hazel branches as larvae dug the galleries ©Agrion

PEST CYCLE & BIOLOGY Beech splendor beetle completes one generation per year and overwinters as larvae in woody tissues. The eggs are usually laid on the sun-exposed sides and 1-2 m from the ground level. Hatching occurs after 8-12 days, then the young larvae penetrate the bark of the trunks. Larvae feed on woody tissues, digging serpentine galleries upwards and towards the base. Larvae complete the development in autumn. Mature larvae go under the tree bark to overwinter.

Larva digging galleries under the tree barks, egg masses on the bark surface and mature larva in a gallery ©nocciolare.it ©Ferenc Lakatos, University of Sopron, bugwood.org

MEANS OF CONTROL Long flight period makes difficult setting the right protection program. Agronomical aspects: July to August, monitor the presence of adult insects, egg masses on the cork, plant vigour • From and drying up of apical canopy part. monitoring technique proves to be frappage in early morning hours. • Best Carry autumn pruning of the infested plant parts. • Removeoutand burn pruning remains. • For chemical treatments, products based on lambda-cyhalothrin and spinosad are authorised for the use in Italy. Applications are performed against adults usually at the end of May.

PEST CONTROL STRATEGY

MONITOR THE PEST PRESENCE ON THE TREES

APPLY INSECTICIDES WHEN RECOMMENDED

PRUNE AND REMOVE THE INFESTED PLANT PARTS

ANTHRACNOSE Scientific name: Piggotia coryli Symptoms: Brown, burn-like leaf areas, dark patches on male flowers

PEST DESCRIPTION Anthracnose is a foliage disease caused by Piggotia coryli that appears in particularly rainy years and with increased average humidity. It is mainly set on leaves and buds, occasionally even on twigs causing them to dry out. The first symptoms appear in spring and are visible on male flowers which have dark brown parts. Buds infected at the beginning of the vegetative growth turn brown and detach easily. Sometimes, they can produce shoots that are weak and decay soon. In early summer, on affected leaves, brown-reddish spots surrounded by pale green halo appear. These leaves drop before the healthy ones. Generally, on the infected plant parts pathogen is visible in the form of small brown points. If not exceeding the threshold, anthracnose could stress and weaken the plant making it more susceptible to other threats. When the plant is already weak or stressed by other environmental factors IS MORE SUSCEPTIBLE to anthracnose and other diseases.

Anthracnose symptoms and damage on hazelnut ©NOCCIOLO SERVICE; Damaged male flowers ©Regione Campania ‐ Assessorato Agricoltura

PEST CYCLE & BIOLOGY Piggotia coryli produces fruiting bodies on all infected plant parts. It overwinters on infected leaves remaining on the soil or branches on the trees. Like for other described fungal diseases, anthracnose occurs with cool and moist weather. Spore dissemination happens with wind and rain infecting newly emerged leaves, buds and twigs. Symptoms start to appear in mid to late summer. The level of disease severity is directly related to duration of the warm and humid periods. The fungus growth is inhibited when the temperature is above 12 °C.

Irregular spots and burned stains on lef surfaces caused by Piggotia coryli - Anthracnose of hazelnut ©Agrion

MEANS OF CONTROL DISEASE MANAGEMENT Chemical

• Fungicides are usually applied at the beginning of leaf fall. coverage of the apical tree parts and good product penetration in the canopy must be ensured • Aforgood effective disease control. • Generally, Piggotia coryli is controlled with copper-based treatments.

Irregular spots and burned stains on lef surfaces caused by Piggotia coryli - Anthracnose of hazelnut ©SAGEA

Agronomical aspects enhance tree vigor and improve the air circulation in the orchard, manage properly the spacing • To with pruning. the disease overwinters on leaves, to reduce the infection for the following season remove the • Since fallen leaves and other plant litter during the autumn.

POWDERY MILDEW Scientific name: Phyllactinia guttata, Erysiphe corylacearum Symptoms: White, powdery stains on both leaf sides and fruits, leaf roll-up and fall

PEST DESCRIPTION Powdery mildew is a fungal disease widely known by farmers and easily recognizable. The fungus usually appears in late season with white, powdery stains on the leaves’ underside and it is generally considered as a minor disease. However, in the Black Sea region, where the disease is well established, new and more dangerous forms of powdery mildew might occur. Symptoms appear in spring and might represent a threat to plants causing leaf roll-up and fall, immature buds, decreased resistance to cold winter and reduced vegetative growth in the following spring. Powdery mildew symptoms are also visible on fruit husks.

Typical white spots on leaves caused by powdery mildew ©R. Botta, DISAFA, University of Torino

PEST CYCLE & BIOLOGY One form of Powdery Mildew caused by Phyllactinia guttata overwinters in a globose, closed fruiting body bearing the ascospores inside. These fruiting bodies stick to leaf and bud surfaces with a sticky substances. Mature bodies burst along the middle line releasing the spores over leaves, buds and shoots. As the fungus becomes established it begins to produce chains of white conidia (asexual spores) on the surface of the leaves. These can become abundant, giving the leaf a white powdery appearance. The conidia are readily disseminated by the wind.

Leaf underside with Powdery mildew fruiting bodies which eventually break and release the spores - Phyllactinia guttata ©Willem Ellis (Plant Parasites of Europe)

MEANS OF CONTROL Preventative cultural practices: Pruning to an open canopy to maximize air movement and reduce humidity in the canopy.

Chemical control: check and preventative spraying during the period in which the plant is particularly susceptible • Spots to the disease are essential. The presence of overwintering inoculum is an important factor. If in the previous year infestation • was high, conduct appropriate fungicide applications in early spring to minimize new infections. Curative applications have been proven less effective. Moreover, they are at high risk of encouraging • the development of resistant strains. Chemical control • or sulphur. is based on authorised active ingredients with fungicidal activity, such as boscalid active ingredients authorized on hazelnut may vary across countries. The indications present • The in the label of each product must always be followed in order to perform the application correctly.

As a result of the mildew infestation, at the underside of the leaves, the leaf margins strongly curve downwards. When performing the treatments, good cover of the canopy must be ensured ©Willem Ellis (Plant Parasites of Europe)

CYTOSPORA CANKER Scientific name: Cytospora corylicola Symptoms: Red/orange exudates on the bark, necrosis underneath the bark, dried branches with attached leaves

PEST DESCRIPTION Cytospora canker is caused by species from Cytospora genus. Present in the hazelnut-cultivating areas worldwide, the disease is caused by fungus Cytospora corylicola. The fungus attacks stressed plants and already damaged tissues. Up to the recent years, Cytospora canker was considered a minor problem in Italy. However, the disease increased in incidence and severity, attacking even young orchards.

With the beginning of spring, and when temperature and humidity increase, the fungus sets on damaged tissues forming red/orange exudates in the form of gummy drops on the tree bark. ©SAGEA

PEST CYCLE & BIOLOGY The fungus overwinters in the bark of the branch either as pycnidia or as mycelia. Cytospora conidia present in gummy exudates are easily transmitted with insects, wind or rain splashes. Fungus spreading occurs from May to September in presence of rain and high humidity events. Fungus colonizes plants through natural, accidental wounds such as hailstorm or strong wind damaged branches.

Fungus develops along the trunk Inner barks appears necrotic. Necrosis of underlying woody tissue extends radially into the trunk. ©Jay Ram Lamichhane, Alfredo Fabi and Leonardo Varvaro

MEANS OF CONTROL The control measures are of a preventative type. Agronomical aspects: weak and old damaged trees from the orchard • Remove and plant healthy plants. out balanced fertilization and optimal irrigation. • Carry suitable terrain and soil conditions to avoid • Maintain water lodging. pruning, remove from the orchard and burn • During infected branches

UNDERSTAND PEST SYMPTOMS

RESPECT THE INSTRUCTIONS ON PRODUCT LABEL

APPLY PREVENTATIVE MEASURES

Chemical measures of heavy infections apply copper-based products (max 4kg ha/year) at the end of summer • Inandcase when the vegetation restarts to grow • Protect pruning wounds Authorized active ingredient for the use in Serbia is pyraclostrobin. It is applied preventatively, at the onset of conditions suitable to disease development, when vegetation restarts the cycle and in October before the first leaf fall.

Infected branch tissue dries while leaves remain attached. When not properly managed all the branches can be killed. ©Leonardo Varvaro

HAZELNUT MONILIA Scientific name: Monilia coryli Symptoms: Necklace or pearls like forms on the immature fruits, pale brown or greenish, thin hazelnut skin becomes more brown

PEST DESCRIPTION Diseases caused by fungi from Monilinia genus are known as brown rot diseases or moniliosis. Fungi from Monilinia genus have numerous hosts, among which the mostly attacked are peaches, nectarines, plums, cherries, etc. Under particular climate and soil conditions, mostly in warm and humid areas, Monilia attacks hazelnuts. Among all species, hazelnut is a host plant of 3 species Monilia coryli, Monilia laxa and Monilinia fructigena which appears predominantly. Prematurely attacked fruits tend to gain more brown color and then shrivel. In hazelnut, this fungus attacks young fruits and organs that are soft and succulent, and not yet lignified. Therefore, infections are possible up to the stages prior to lignification of the nut shell.

Hazelnut monilia on immature fruits where you can notice the jewelry-like structures. Formed colonies appear without the color or white. ©Christoph Hoyer

PEST CYCLE & BIOLOGY Monilia are fungus that spend the winter mostly in cankers formed on twigs, branches, buds. The disease is air-born and spread by rain splashes. Primary inoculum occurs in Spring, as the spores are released from the infection sites. Rainy and foggy weather create suitable conditions for disease development. The fungus also spreads to healthy organs when they are in proximity of infected parts. Optimum temperature for fungi growth is 24°C but the infection can occur at temperatures as low as 10 to 15 °C.

Symptoms of hazelnut monilia – shriveling and discoloration on immature fruits with jewelry-like structures. ©Dr. Darko Jevremović, Fruit Research Institute Čačak

MEANS OF CONTROL The control of hazelnut brown rot can be summarized as follows: of infected shoots and fruits as they can contaminate healthy parts. • Removal Fungal pathogens resistance to fungicides quickly, therefore the instructions written • on the labels MUSTcanBE develop STRICTLY FOLLOWED. disease mechanism on hazel trees is not very well known. Hence, CONSTANT MONITORING • The of plant health is absolutely necessary. fruit growing, especially after rainy and foggy periods, hazelnut farmers are advised to inspect • During the orchard screening for the presence of brown rot symptoms. case you notice similar appearance, to avoid spreading and economical losses, is necessary to • Incontact your technical support. Chemical control can be conducted with fungicides based on boscalid. •

Symptoms of hazelnut monilia – shriveling and discoloration on immature fruits with jewelry-like structures. ©Christoph Hoyer

BACTERIAL CANKER Scientific name: Pseudomonas avellanae Symptoms: twig and branch wilting, brown tissues

PEST DESCRIPTION In the year of 1976, for the first time bacterial canker was observed in the northern Greece. Afterwards, it was spread widely in Turkey and Italy. The bacterium causes extensive twig wilting and dieback, canker formation along trunk and plant death. The fast wilting of the branches during spring and summer and browning of woody tissues underneath the cork are the main disease manifestations. In autumn, cankers develop on branches and on the trunk. Diseased bark turns reddish brown, and a brown discoloration of the sapwood is apparent if the bark is stripped from the branch.

During summer, diseased European hazelnut trees exhibit rapid wilting and branch dieback(a). After the wilting, the desiccated leaves remain firmly attached to the branch throughout the growing season ©Scortichini, 2002

PEST CYCLE & BIOLOGY The pathogen systematically migrate through woody tissues. In autumn, it invades the plant through the wounds on leaf but any scar can serve as an entry point. From the leaves, infection spreads to the stems and shoots and eventually to the base of the plant. Environmental factors also play an important role in disease spread. Moreover, infections may be favored by high soil acidity, poor cultivation practices as planting very deep, use of acidic fertilizers such as ammonium sulfate, high levels of aluminum in soils, and high levels of iron and manganese in the roots. Frost and hail injuries may also favor disease spread. After spring frosts, P. avellanae may also colonize wounds associated with frost cracks on branches and trunks.

Life cycle of Pseudomonas avellanae related to central Italy where spring frosts occur often. After the spring frosts, Pseudomonas avellanae can infect the cracks and wounds made by frost ©Scortichini, 2002

MEANS OF CONTROL

INTEGRATED MANAGEMENT OF BACTERIAL CANKER

AGRONOMIC TECHNIQUES FOR INOCULUM DESTRUCTION to avoid spreading of • Fundamental inoculum. of wilted branches and twigs. • Removal Disposal from the orchard and burn the • infected plant material. In case the entire tree is wilted, eradicate • it together with roots and suckers

of orchards for early disease • Monitoring symptoms is essential. control methods rely on protection • Chemical of foliar wounds with copper-based products and minimum dosage from the label.

this bacterium lives inside the plant, the • Since efficacy of copper-based compound is low.

CHEMICAL CONTROL Copper treatments at critical moments Why? To reduce the possibility that wounds are colonized by bacterium Apply copper-based chemicals immediately after pruning, spring frost, hail, windy storms in early autumn and at the beginning and middle of leaf drop.

INDUCE PLANT RESISTANCE

Application of Plant Resistance Inducers Why? To reduce the number of dead trees and brunches Acibenzolar-S-methyl (CGA 245704, by Syngenta Crop Protection), registered in Europe as Bion. 5 applications Once a month From late April to July

PEST SYMPTOMS

Rapid wilting European hazelnut leaves in early spring caused by Pseudomonas avellanae longitudinal canker on a stem of European hazelnut caused by Pseudomonas avellanae ©Scortichini, 2002

Canker on a stem, damaged hazelnut bark, and brown tissue underneath the bark ©Scortichini, 2002, ©atlasplantpathogenicbacteria.it

• Bacterial canker survives harsh weather in the bark of the roots but also branches. • As vectors, insects can potentially spread the bacterium from infected to healthy tree. • More acidic soils might also make the plants more susceptible to bacterial canker.

BACTERIAL BLIGHT Scientific name: Xanthomonas arboricola pv. corylina Symptoms: Dark brown, angular lesions on leaves, husks and fruits, twigs dieback and canker

PEST DESCRIPTION Xanthomonas arboricola pv. corylina is a causal agent of hazelnut bacterial blight. It is present in all the major production areas globally. Up to the recent years it was particularly dangerous for the nurseries. Nowadays, it is spread and damages hazelnut orchards in cultivation. Development of disease symptoms is influenced by climate conditions. When the humidity is high, with rainy periods, bacterial blight symptoms appear earlier. First symptoms manifestations in spring. Among the symptoms, the most characteristic are brown angular stains on leaves, fruit husks and nuts. The symptoms on twigs and stems are visible in spring and summer. Wooden tissue underneath the bark becomes brown and reddish. The disease rarely causes plant death but could influence the yield if not adequately controlled.

Symptoms on hazelnut leaves and husks ©SAGEA; the second image in the first row and the last image in the row below ©Scortichini et al., 2016

PEST CYCLE & BIOLOGY Infections occur indirectly, through the wounds. Cankers formed in the previous season (late summer) on the branches and trunks are the most important sources of primary inoculum in the field. Drops of exudates containing plenty of bacteria disperses from cankers when raining. These drops infect the buds. is spread by rain splashes or infected plants from nursery. • Bacterium Disease incidence on mechanical factors such as pruning and weather (rain and wind). • Bacterium is capabledepends to survive 4 months on the fallen leaves and doesn’t overwinters in soil. • This bacterium is thermophilus and the optimum temperature for its development is 18°C - 22°C. •

Bacterial blight on hazelnut in nursery ©Scortichini et al., 2016; Symptoms on the trunk ©SAGEA

MEANS OF CONTROL For this disease there is no curative methods but preventative ones could limit the presence of the disease. water treatments to protect hazelnut nursery stock 42°C for 45 minutes. • Hot Avoid unfavorable planting sites and improve soil drainage. Bacterial blight incidence is highly correlated • to stress caused by cultural practices and unfavorable pedoclimatic conditions. Keep balanced nitrogen fertilization and prefer the use of organic fertilizers. • If the disease gets established: - cut and burn infected twigs and branches. • Mechanical Chemical, preventative • substance per year). treatments with various copper-based products (maximum 4 kg/ha of active preventative treatments to be applied in autumn, in spring before the vegetation • Recommended starts to burst and at the beginning of vegetative phase (4th-5th leaf).

Symptoms on leaves and branch ©SAGEA

•

Damage caused by Xanthomonas arboricola pv. corylina is due to reduction in leaf surface and mass, drying of bud bearing shoots and branches. • Long term consequences are loss in vigor and yield. • Bacterial blight is particularly harmful in nurseries and plantations 1-4 years old.

PEST SYMPTOMS

Initial stage might not be obvious. You might see only yellow, pale green chlorosis.

Progressed disease shows brown angular lesions.

• Damage caused by Xanthomonas arboricola pv. corylina can be noticed on almost all plant parts, however, the most obvious indications you can find on leaves. • First you might see yellow spots without brown lesions, while as disease advances brown, burn-like forms appear spread on the entire leaf surface.

APPLE MOSAIC VIRUS Scientific name: Virus mozaika jabuke - ApMV Symptoms: chlorotic and yellow patterns like mosaic on the leaves

OPIS ŠTETNOG ORGANIZMA Apple Mosaic Virus (ApMV) is the most significant viral disease of hazelnuts. Its symptoms were recorded in Bulgaria, Turkey, USA, Italy, Poland and Spain on hazelnut trees. The most common symptoms are chlorotic, yellow mosaic patterns on the leaves. However, infected plants might as well be completely asymptomatic. Trees might show slight reduction in growth and yield. Symptoms are evident early in the growing season but with time and temperature increase they might appear partly masked.

ApMV producing irregular yellow line patterns and ringspots on hazel leaves ©Dr. Darko Jevremović, Fruit Research Institute Čačak

PEST CYCLE & BIOLOGY ApMV is not transmitted by vector and is not pollen- or seed-borne. The virus is graft-transmissible and usually spread by vegetative propagation or by mechanical inoculation. It persists in propagative material, budwood and grafted nursery plants, which represent fundamental source of infection. In nurseries, it is usually spread through the soil via grafted roots. It is also known that ApMV can be present in weed species in hazelnut orchard.

ApMV symptoms on hazel leaves ©Dr. Darko Jevremović, Fruit Research Institute Čačak

MEANS OF CONTROL PREVENTATIVE MEASURES: The most effective method of controlling viral diseases is to set virus-free plantations with certified planting materials. Therefore, planting of healthy trees and testing on pathogen status is an important preventative measure.

CULTURAL PRACTICES: To prevent the virus spreading, certain cultural practices play an important role. Weeds are not just nutrient-robbing plants, but are also secondary hosts for viruses. Hence, should be properly managed. In this regards, weeds in focus are not only the species present within the orchard, but also ones that are in nearby surrounding.

Screening for pathogen status

I TIF

Healthy, virus-free planting material

VIRUS CONTROL

Weed management

PHYSIOLOGICAL DISORDER – BROWN STAINS Symptoms: yellowish brown to dark brown spots on the nut shell, brown stained nut shells with presence of exudate

DISORDER DESCRIPTION Brown stain is known as a physiological disorder of hazelnuts since neither pathogens nor pests are associated with these sympthoms. Brown stains can be described as brownish liquid that comes out on the sides or apical part of nuts. Defect starts to appear when the nuts are half mature. The first visible symptoms are small brownish watery spots on the green, immature shell. The internal area, at this stage, remains unaffected.

Symptoms of brown stain ©Dragan Nestorović, elektra, bugwood.org

In the later stages of development, staining is visible on the maturing kernel. At times the defect might cover the entire kernel that turns into soft, brown, watery mass. It might happen that whitin the same bud, some kernels remain without brown stains. Eventually, brown staining is a disorder that causes blanks or poorly filled nuts. The shell itself is softer in the affected area.

Symptoms of brown stain ©Dragan Nestorović, elektra, bugwood.org

Brown stains cause ununiform kernel discoloration. In extremely severe cases, the shell is distorted and the kerrnel completely ruined. The exact cause of the disorder is not yet fully understood, therefore control measures that should be taken to avoid its occurrence are not defined. Varietal susceptibility to the incidence of brown stain disorder has been observed. The varieties Barcelona, Tonda Gentile delle Langhe, and Imperiale de Trebizonde show high susceptibility to brown stain, whereas brown stain disorder is extremely rare in Willamette and Negret varieties.

Symptoms of brown stain ©Dragan Nestorović, elektra, bugwood.org

DAMAGE CAUSED BY EXTREME WEATHER CONDITIONS

DAMAGE CAUSED BY EXTREME WEATHER CONDITIONS Conditions: Early spring frost, hail, waterlogging

DESCRIPTION Hazelnut production is particularly dependent on environmental and climate conditions. The most significant cultivating areas are usually near large water reservoirs like Black and Mediterranean Sea and Pacific Ocean. EARLY SPRING FROST might interrupt pollination, damage current season’ shoots, leaves, pollinized female clusters and young branches. Orchards laying on high elevations (500 m a.s.l) are often affected. Serious crop loss might happen when the temperature drops below 0°C in March or April. Influencing the yield, heavy frost events condition prices and export.

The 1st picture is the phenological stage of the hazelnut that might be affected by the early spring frost and on the 2nd bud that is already affected and might be damaged with the ice ©nhgardensolutions.wordpress.com

HAIL DAMAGE can occur at any point during the growing season and make an impact. When the hail storm happens early in the growing season, the damage and consequences are much higher. Hailstone size and intensity will also determine how much damage the fruits receive. PEST & DISEASE RISK – Hail damage such as branch breaking, wounds on stems and twigs might open the space for pathogens. At severe hail storm events:

can be stripped of leaves and fruit • Trees • Leaves can be bruised, torn and with holes

Hail storm damage on hazel trunk and brunches ©Agriser

WATERLOGGING – There are a number of consequences resulting from constant water accumulation in the orchards. For the hazelnut trees waterlogging is considered as a condition of a plant stress. When the soil is saturated with water, the air in the soil pores is displaced with water. Due to lack of aeration the oxygen supply to the roots is prevented. Prolonged waterlogging can cause alteration of soil acidity and accumulation of toxic products for the roots. Symptoms of waterlogging stress include wilting and chlorosis of leaves due to lack of nitrogen and shoot dieback. Disease risk– Apart from damaging the root system due to lack of aeration, diseases are favored by wet and humid conditions. Therefore, when the soil is waterlogged the humidity will be much higher contributing to increasing disease pressure.

Landlock water due to excessive water entry and flooding on the field ©shutterstock.com

MEANS OF CONTROL Management of hail damaged hazel trees:

• • • •

Inspect the damage of hazel trees as soon as possible after the hail event Pruning of damaged plant parts after the hail storm Hail wounds on the trees and bark may need a fungicide to prevent pest and disease entry Where practical, large wounds on trunks and branches should be covered with a water-based paint to avoid desiccation and disease infection

Management of waterlogging in the orchard:

• •

The best proven strategy is to drain or pump water from the orchard within 48 hours For the large surfaces spoon drain dug can facilitate water movement

Kopanje drenažnih kanala

Damage caused by hail in hazelnut orchard goes to a much less extent compared to apples, pears, and fruits with a soft flesh.

GOOD PRODUCTION PRACTICE

TREATMENT TECHNOLOGY CALIBRATION OF MACHINES, TIME AND AMOUNTS OF SPRAYING KEY POINTS TO CONSIDER BEFORE YOU TREAT YOUR HAZELNUTS This page provides key points to be considered before spraying your hazelnut orchard. Proper determination of spray volume and calibration of the sprayers are essential for high-quality applications, as pesticides must reach homogeneously all parts of the canopy. EU directive on sustainable use of pesticides (EC 2009/128) provides guidelines for environmental and operator’s safety practices and optimal on-crop product deposition, and states that : “Professional users shall conduct regular calibrations and technical checks of the pesticide application equipment”.

WHY IS IMPORTANT ?

CALIBRATING PESTICIDE SPRAYERS

There are many factors that influence the success of a treatment: product used, dose and timing of spray, pest biology, environmental conditions, quality of pesticide distribution. Indeed, effective pest control relies on properly calibrated equipment! BEFORE YOU PERFORM TREATMENTS it is neccessary to inspect the conditions of your equipment. • You should search for leaky hoses, faulty nozzles, screens and filters, boom height, pressure gauges. • To apply pesticide mixture uniformly in a precise area you need to adjust speed, nozzle orifice size and pressure.

AS AN OPERATOR YOU NEED TO

• • • •

Introduce yourself with all sprayer functions. Inspect the conditions of all equipment parts. Select appropriate nozzles and determine their height. Calibrate the equipment you will personally use

NOZZLES

AIR FLOW ADJUSTMENT

..are critical part of a sprayer. Their function is to regulate the flow, atomize the mixture into droplets and disperse the spray. Each nozzle on a sprayer should apply the same amount of pesticide. Nozzles type, configuration and number should be adjusted when your sprayer is filled with water only. Nozzles must work properly to control dripping when spraying stops!

Air flow should be big enough to reach inside the canopies, still not so strong to blow the spray through the trees causing spray losses. This is achieved when hazelnut canopy is filled with the spray and there is no spraying cloud on the next row. With young plantations lower air flow is recommended. Dense canopies require stronger air flow so that product penetrates inside the canopy.

SPRAY VOLUME DETERMINATION Hazelnut trees have large canopy dimensions (up to 4.5-6m in height and 5.5 m in width). Applied product must pass through 2.5-3 m inside and through the apical part of the canopy. Recommended water volume is usually 1000 L/ha. However, there are ways to determine more accurately the spray volume you need based on the characteristics of your ochard.

MARKING TEST AREA and MEASURING WATER USED your sprayer with water only. • Fill Mark • the test area on the field where the pesticide is to be applied. Tested area (m2) = Lenght (m) x Width (m) test area and measure the amount of water used by refilling to the original level. • Spray If knapsack - Your sprayer should be sitting on level ground when reading the volume remaining in the tank. • When spraying, along the measured distance at your regular spraying speed. • Calculate Liters walk/drive of water needed per hectare (L/ha) with the formula: •

Water volume (L/ha) =

Water used (L) x 10 000 m2/ha Tested area (m2)

Read the label to determine the pesticide application rate. Calculate the total amount of pesticide you will need for the entire area that must to be sprayed and the total amount of liquid mixture. Calculate the amount of pesticide needed for each tank for the desired application rate.

TREATMENT TIMING If treatment timing is accurate, most probably you will need to perform fewer treatments. The first consideration is to follow the weather forecasts for the day of planned treatment but also for some following days. In most cases treatment timing is determined according to the target pest since the optimal timing depends on pest biology. For example, for BMSB or common stinkbugs the best timing is to apply treatments at dawn (4.00 -5.00 am) when the insects are less active.

COMPATIBILITY OF ACTIVE SUBSTANCES TANK MIXING ERRORS The act of combining multiple products in a tank is called tank mixing. There are several factors to be considered when crop protection products are needed to be mixed in a single application. Some of the basic factors are product formulation, order according to which products are put in a tank, and carrier type.

PRODUCT INCOMPATIBILITY

PHYSICAL INCOMPATIBILITY

CHEMICAL INCOMPATIBILITY

Product doesn’t suspend

The solution might look pretty well, but…

Aggregate together in crumbs Injures the crop when applied Product doesn’t dissolve

Reduces each product effectiveness

Creates oil residues in a tank

CONSEQUENCES Solution appears in layers

Mix excessive foaming

Physical product incompatibility problems can block the sprayer while chemical incompatibility might injure crops or reduce product efficacy. Both cause economical and time losses.

WHAT CAN GO WRONG? Each product used in crop protection contains a set of complex chemical structures. When 2 or more products are mixed, there is a potential risk for negative interactions - incompatibilities. It might happen that one product influences how the other disperses and performs. Physical incompatibilities might prevent the product to dissolve forming a cake-layer on the bottom. Products might form crumbles, gel or paste, clog the nozzles and make tank very difficult to clean. Physical incompatibilities cost you time and effort of cleaning the sprayers. Chemical incompatibilities reduce spray quality, yield and might cause injuries to plants, which can be visible few hours or days after the treatment. More products you add in a tank, greater is the risk of incompatibility.

7 COMMON MISTAKES WHEN PREPARING A TANK MIX

1 2 3 4 5 6 7

LABEL INSTRUCTIONS NOT FOLLOWED

NO PREVIOUS MIXING TEST PERFORMED

PRODUCTS MIXED IN A WRONG ORDER

INSUFFICIENT AMOUNT OF WATER FOR DISSOLVING ALL PRODUCTS

ADDED PRODUCTS NOT DISSOLVED BEFORE ADDING

INADEQUATE AGITATION, TOO LITTLE OR TOO MUCH (creates foam)

FERTILISER AS A CARRIER DISSOLVES LESS PRODUCT THAN WATER

Photo credits ©Purdue Pesticide Programs

HOW TO AVOID TANK-MIX INCOMPATIBILITIES? 1. INSPECT THE PRODUCT IN ORIGINAL CONTAINER FIRST Some of the product formulations might appear in layers when left in the storage. Mix such products so to ensure they are homogeneous before adding it in the tank. 2. READ MIXING INSTRUCTIONS GIVEN ON THE LABEL Follow indicated mixing order and recommended carrier volume. 3. RESPECT THE MIXING ORDER Generally, mixing order is: 1. wettable powders (WP), 2. water-dispersible granules (WG), 3. flowable liquids (FL) or suspension concentrates (SC), 4. emulsifiable concentrates (EC), 5. soluble liquids (SL) or soluble powders (SP), 6. Any crop oils and/or surfactants should be added last. 4. USE THE CORRECT WATER VOLUME Before the first product is added, there must be the minimum volume of water in a tank (usually 50-70% full of water) 5. MIX THE SOLUTION CONTINUOUSLY The solution in a tank must be stirred before and during the treatments. Otherwise, the products that have dispersed active ingredients will fall to the bottom over time. Set moderate agitation, over-agitation can cause foaming or clumping. 6. ENCOUNTER THE CARRIER DIFFERENCES Water is generally used as carrier, however you might need to use a fertilizer which is a concentrated salt solution and has less water available to disperse dry formulations. Before mixing products in a fertilizer, test the compatibilities in a jar.

READ THE LABELS OF ALL PRODUCTS YOU INTEND TO MIX

SHAKE PRODUCTS BEFORE MIXING IN A TANK

FILL THE TANK WITH 50-70% OF PLANNED WATER VOLUME

ADD PRODUCTS IN TANK BASED ON THEIR FORMULATIONS

AFTER YOU PUT DRY FORMULATIONS WAIT 5 MINUTES

ADD REMAINING WATER TO THE TANK

START WITH AGITATION WHEN YOU ADD WATER, BEFORE ADDING THE FIRST PRODUCT

GOOD PRODUCTION PRACTICE HEALTH AND SAFETY AT WORK SAFE PRACTICES AND PERSONAL PROTECTIVE EQUIPMENT (PPE) This chapter is developed according to the legislation currently in force – for personal protective equipment, storing and handling empty plant protection product’ packaging. All the legislation references are included in the reference list at the end of this guideline.

EXPOSURE ROUTES Skin is the most common route of pesticide entry into the body. Second important entry route is by ingestion or inhalation. When you are handling pesticides AVOID:

• Smoking and eating • Drinking Holding your mobile phone • As this way you can ingest pesticides!

CONTACT WITH PESTICIDES DIRECT CONTACT

INDIRECT CONTACT

• • • •

• • •

Measuring pesticides

Outside surface of sprayer

Mixing/loading a sprayer

Personal protective equipment

Performing applications

Sprayer nozzles

Storing pesticides

Photo credit ©SAGEA

RECOMENDED PERSONAL PROTECTION EQUIPMENT

Protective clothing should belong to standard EN 468 category III, type 5 or 6.

Clean the goggles immediately after use.

Full or half-face respirator mask with filters A2 (for chemical volatiles) and FFP3 (for dust) approved for pesticides must fit your face tightly. Chemical-resistant, nitrile gloves prevent pesticide entry. They should be according to standard EN374.

Wear unlined neoprene or butyl rubber boots with socks underneath.

FEW SIMPLE RULES YOU NEED TO KNOW AND APPLY long-sleeved shirts and pants offer minimal protection, minimize THE RISK using personal • Your protecting equipment. coveralls – protective chemical-resistant clothing over the long sleeved cloths and pants. • Wear protective chemical-resistant clothing when mixing, loading or spraying pesticides! • Wear Disposable clothing is single use only! • Contaminatedprotective protective clothing, after use should be disposed in the same manner like empty pesticide • packaging. the hat for more skin coverage. • Wear follow the instructions on labels. • Always Don’t store • laundry. your PPE with everyday cloths and wash your protective clothing separately from other

KEY POINTS Every time you spray pesticides you expose yourself to hazardous substances. There are many situations on the field when small quantities of pesticides enter your body on a regular basis without you being aware of it! FOLLOW SAFE WORK PRACTICES AND WEAR PPE!

Worldwide, farmers are more susceptible to developing diseases caused by continuous pesticide exposure than the other people. READ PRODUCT’s SAFETY DATA SHEETS TO UNDERSTAND THE DANGER!

STORE YOUR PRODUCTS PROPERLY SAFETY AND SECURITY when storing plant protection products are of high importance and should be performed in accordance with following rules: Order in the storage - Classify the products into categories INSECTICIDES, FUNGICIDES, HERBICIDES… Keep pesticides in their original packaging and close tightly the open bags of dry formulations so to prevent humidity from influencing product quality.

on which you store products should be • Racks made of corrosion resistant material. formulations should be kept at lower racks • Liquid compared to dry formulations (in case of spilling out the liquids)

the racks in a way to ensure good ventilation, • Place sufficient air flow and make the cleaning easier. Leave enough distance from the walls and between the racks too!

store your Personal Protective Equipment in • Don’t the same storage where you store products..

most of pesticide • On labels indicated storage temperature is 5 -15°C.

record of buying pesticides and their • Keep shelf life. Use the ones that first entered your storage and later the new batch.

79 not stockpile! Reduce storage needs by buying • Do only the amount of pesticide that you will need during the current season

store pesticides in application • Never equipment. Only mix the amount needed for the current application.

HANDLING EMPTY PESTICIDE PACKAGING PRODUCT FORMULATIONS dry plant protection product formulations that are used without dissolving, shake well with the last • For use, so to maintain the minimum possible amount of dry product in the empty packagings. dry plant protection product formulations such as hydrosoluble and wettable powders, concentrated • For emulsions, suspension concentrates, water dispersable granules, etc.. containers should be stirred with minimum amount of water that is part of water volume calculation and afterwards put in the reservoir of the sprayer that is to be used for the particular treatment. This way, drying up of product remains in the packaging is avoided.

WASHING USED PACKAGING of empty packaging should be done in three turns or with water under pressure. Please, follow • Washing the following steps: 1. 2. 3. 4. 5. 6. 7.

Pour the content from the packaging into sprayer reservoir and wait 30 sec for the remains to drain. Add water up to 1/3 of the packaging volume. Close the packaging and shake well, so that water reaches entire inner surface. Pour the water in the sprayer reservoir and wait 30 sec for the content to drain. This procedure should be repeated 2 times more, always using clean water. Pierce the backaging on three marked spots so to make it unusable. Dispose packaging according to the instructions on the label.

CALENDAR OF HAZELNUT PROTECTION

CALENDAR OF HAZELNUT PROTECTION PHENOLOGICAL STAGES OF HAZELNUT

Overwintering buds

1st-2nd leaf developed

Ovary visible

Post-Harvest

Flowering, male and female flowers

3rd leaf developed

4th – 5th leaf developed

Seed growth I and II stage

Leaves start to fall

½ of leaves fallen

Bud breaking

Fruit set

Nut formed

All leaves fallen

PROTECTION OF PRODUCTIVE PLANTATIONS This table represents an indicative list with moments of interventions and proposed active ingredients. It is very important to follow the appearance of pests and diseases in the orchard and to react according to established thresholds.

Moment of Intervention

Pest Common Name

Pest Scientific Name

Type of Product

Active Substances approved in Serbia (on March 1st, 2020)

Overwintering buds

Hazelnut Leucanium Scale, Big Bud Mite

Eulecanium coryli, Phytoptus avellanae

Insecticide, acaricide

Paraffinic mineral oil, Sulphurbased

Flowering

Bud breaking

At this phenological stage no treatments should be applied. Cytospora canker

Cytospora corylicola

Fungicide

Copper

Bacteriosis

Xanthomonas arboricola pv. corylina

Fungicide

Copper

Big Bud Mite

Phytoptus avellanae

Acaricide

Sulphur

Hazelnut Leucanium Scale

Eulecanium coryli

Insecticide

Paraffinic mineral oil

3rd leaf developed

Big Bud Mite

Phytoptus avellanae

Acaricide

Sulphur

With the formation of the first colonies, usually when the leaves start to unfold

Hazelnut aphid

Myzocallis coryli

Insecticide

Paraffinic mineral oil, Acetamiprid, Deltamethrin, Abamectin

4th – 5th leaf developed

Bacteriosis

Fruit set

Beech Splendor Beetle

Agrilus viridis

Ovary visible

Nut weevil, common stink bugs

Curculio nucum, Nezara viridula, Gonocerus acuteangulatus , Palomena prasina

Seed growth I stage

Nut weevil

Curculio nucum

Insecticide

Deltamethrin

Common stink bugs

Nezara viridula, Gonocerus acuteangulatus , Palomena prasina

Insecticide

Lambda-cyhalothrin

Brown Marmorated Stink Bug

Halyomorpha halys

Insecticide

Deltamethrin, Lambdacyhalothrin

Seed growth II stage

Nut formed

Post-Harvest

Fungicide

Beech Splendor Beetle

Agrilus viridis

Cytospora canker

Cytospora corylicola

Beech Splendor Beetle

Agrilus viridis

Cytospora canker

Cytospora corylicola

Copper

Anthracnose

Piggotia coryli

Fungicide

Copper

Leaves start to fall

Hazelnut Leucanium Scale

Eulecanium coryli

Insecticide

Paraffinic mineral oil

½ of leaves fallen

Bacteriosis

Xanthomonas arboricola pv. corylina

Fungicide

Copper

All leaves fallen

Bacteriosis, Cytospora canker

Cytospora corylicola

Fungicide

Copper

For copper-based fungicides maximum of 4 kg/ha per year of active substance!

PROTECTION OF YOUNG PLANTATIONS POTENTIAL PESTS IN YOUNG HAZEL PLANTATIONS Managing young hazelnut plantations relies of the application of the same authorized products as in protection of productive plantations. However, the main focus in protecting young plantations is on bacterial, fungal and viral diseases. Young hazels can develop disease problems especially during spring when foliage is soft.

Big Bud Mite - Phytoptus avellanae Big Bud Mite can infest and kill the buds at development stage, overall slowing down the growth of young trees. It can be effectively controlled by manual removal of affected buds in winter.

Bacterial blight - Xanthomonas arboricola pv. corylina Bacterial blight causes serious losses in nurseries and young hazelnut plants (1-4 years old).. Chemical products used to prevent the incidence of bacterium are copper-based and applied in the early spring, in the summer and in autumn.

Weed management Weeds compete for moisture and nutrients. Therefore, their control in young orchards is important. Usually, it is performed by soil tilling or mowing.

Hazelnut aphid - Myzocallis coryli Hazelnut aphid potentially can be found on the underside of young hazelnut shoots and leaves. Hazelnut aphid is usually found in spring and if the infestations are severe insecticide spraying is necessary. Authorized active substances against hazelnut aphid are paraffinic oil, deltamethrin, acetamiprid.

Anthracnose - Piggotia coryli Anthracnose, as a foliage disease, leave the symptoms of irregularly-shaped lesions on the leaves. For chemical treatments of the pest, copper-based products are applied at the beginning of the leaf fall.

Powdery mildew - Phyllactinia guttata The occurrence of powdery mildew in young hazelnut plantations is possible. In case that the disease occurred in the last year, for the following season adequate chemical treatment must be applied. The treatment should be performed when after the visual inspection, powdery mildew symptoms are confirmed. Products used are sulphur-based.

KEEP IT CLEAN Visitors, workers, vehicles can transmit diseases from infected orchard bearing them on tires, boots, tools. All the equipment should be decontaminated before they enter or leave your orchard.

MONITOR YOUR TREES FREQUENTLY

KEY POINTS

PEST CONTROL

If you are familiar with the general conditions of your plants, it will be easier for you to notice unusual symptoms. By early detection you might reduce the economical losses.

APPLYING MORE PRODUCTS AND AT HIGHER DOSES THAT INDICATED ON THE LABELS DOESN’T PROTECT YOUR ORCHARD AND MOST PROBABLY WILL MAKE THE DISEASE MORE RESISTANT. EVENTUALLY, THIS WILL LEAVE YOU WITH LESS CONTROL OPTIONS FOR THE FOLLOWING SEASONS!

REFERENCE LIST 1. Potential geographic distribution of brown marmorated stink bug invasion (Halyomorpha halys). Zhu, Gengping, et al. 2012, PLoS ONE. 10.1371/journal.pone.0031246. 2. Timing of sulphur spray application for control of hazelnut big bud mites (Phytoptus avellanae and Cecidophyopsis vermiformis). Webber, J. and Chapman, R. B. 2008, New Zealand Plant Protection. 10.30843/nzpp.2008.61.6835. 3. Arthropod pest management in organic hazelnut growing. Tuncer, C. 2009, Acta Horticulturae. 10.17660/ ActaHortic.2009.845.90. 4. Insects and mites in the fauna of Serbia – Importance for the classical biological control of weeds. Toshevski, Ivo, et al. 2018. Ecological and economic significance of fauna of Serbia. 978-86-7025-777-1. 5. Aspetti fitosanitari della corilicoltura nel Viterbese (Phytosanitary aspects of hazelnut cultivation in the province of Viterbo). Varvaro L. et al. 2011. Corylus &co., 1, P. 21-37. 6. The ecology and economics of insect pest management in nut tree alley cropping systems in the Midwestern United States. Stamps, W. T., et al. 2009, Agriculture, Ecosystems and Environment. 10.1016/j.agee.2008.06.012. 7. Sprayers. Shenk, Myron. 8. Population densities and seasonal fluctuations of hazelnut pests in Samsun, Turkey. Saruhan, I. and Tuncer, C., 2001, Acta Horticulturae. 10.17660/ActaHortic.2001.556.72. 9. Population density and fluctuations of the Green Shield Bug (Palomena prasina L. Het.: Pentatomidae) in hazelnut orchards of Turkey. Saruhan, I. and Tuncer, C. 2009, Acta Horticulturae. 10.17660/ActaHortic.2009.845.86. 10. La corretta distribuzione degli agrofarmaci nel noccioleto. Corte M. 2014, Rivista di Frutticoltura, 7/8, p. 57-58. 11. Growing Hazelnuts in the Pacific Northwest Integrated Pest Management. Olsen, J. et al. 2013, p. 1-4. 12. Osservazioni su cocciniglia del nocciolo e su Brachytarsus fasciatus. Oliviero, G, et al. 2003, Vol. 6630, p. 1-3. 13. An Integrated Pest Management Strategic Plan for hazelnuts in Oregon and Washington. Murray, K. and Jepson, P,. December, 2018. 14. Effects of transient soil waterlogging and its importance for rootstock selection. Morales-Olmedo, M. et al. 2015, Chilean Journal of Agricultural Research. 2015. 10.4067/S0718-58392015000300006. 15. Occurrence and impact of Agrilus spp. and associated egg parasitoids in hazel groves of Northwest Italy. Moraglio, S. T. et al. 2013, Journal of Applied Entomology. 10.1111/jen.12057. 16. Halyomorpha halys invasion: A new issue for hazelnut crop in northwestern Italy and western Georgia? Moraglio, S. T. et al. 2018. Acta Horticulturae. 0.17660/ActaHortic.2018.1226.58. 17. Hazelnut pests in Serbia. Milenković, S. and Mitrović, M. 2001, Acta Horticulturae. 10.17660/ActaHortic.2001.556.60. 18. Observations on the biology and behavior of Oberea linearis (Coleoptera Cerambycidae) in Sardinia (Italy). Marras, P. M. et al. 2009, Acta Horticulturae. 10.17660/ActaHortic.2009.845.72. 19. Monitoring of the invasive Halyomorpha halys, a new key pest of fruit orchards in northern Italy. Maistrello, L. et al. 2017, Journal of Pest Science. 10.1007/s10340-017-0896-2. 20. Pathogenicity of Monilia spp. to hazel (Corylus). Machowicz-Stefaniak, Z. and Zalewska, E. 2014, Acta Mycologica. 10.5586/am.2000.025. 21. Impact of the invasive brown marmorated stink bug, Halyomorpha halys (Stål), in mid-Atlantic tree fruit orchards in the United States: Case studies of commercial management. Leskey, T. C., et al. 2012, Psyche (London). 10.1155/2012/535062. 22. Extensive Field Survey, Laboratory and Greenhouse Studies Reveal Complex Nature of Pseudomonas syringaeAssociated Hazelnut Decline in Central Italy. Lamichhane, J. R. et al. 2016, PLoS ONE. 10.1371/journal.pone.0147584. 23. Xanthomonas arboricola disease of hazelnut: CURRENT status and future perspectives for its management. Lamichhane, J. R. and Varvaro, L. 2014, Plant Pathology 10.1111/ppa.12152. 24. Review of the chemical control research on Halyomorpha halys in the USA. Kuhar, T. P. and Kamminga, K . 2017, Journal of Pest Science. 2017. 10.1007/s10340-017-0859-7.

87 25. Monitoring damage caused by harmful pests in hazelnut orchards in Samegrelo region, Georgia. Kereselidze, M., et al. 2018. Acta Horticulturae. 10.17660/ActaHortic.2018.1226.57. 26. Monitoring population density and fluctuations of Anisandrus dispar and Xyleborinus saxesenii (Coleoptera: Scolytinae, Curculionidae) in hazelnut orchards. Saruhan, I. 2012, African Journal of Biotechnology 10.5897/ajb11.4185. 27. Biological control and morphological studies on nut weevil (Curculio nucum L. Col., Curculionidae). Akça, I. and Tuncer, C. 2005. Acta Horticulturae 9789066056886. 28. Special issue on the brown marmorated stink bug, Halyomorpha halys: an emerging pest of global concern. Haye, T. and Weber, D. C. 2017. Journal of Pest Science, 10.1007/s10340-017-0897-1. 29. Late spring frosts and its impact on Turkish hazelnut production and trade. Erdogan, V. and Aygun, A. 2017, Information Bulletin of the Research Network on Nuts, p. 25-27. 30. Nocciolo in Piemonte – Linee tecniche per una corilicoltura sostenibile 2019. Corte M. et al. 2019. Agrion, Regione Piemonte. 31. Biological parameters of the invasive brown marmorated stink bug, Halyomorpha halys, in southern Europe. Costi, E. et al. 2017, Journal of Pest Science. 10.1007/s10340-017-0899-z. 32. First surveys on Agrilus spp. (Coleoptera: Buprestidae) infesting hazelnut in northwestern Italy. Corte, M. et al. L. 2009, Acta Horticulturae. 10.17660/ActaHortic.2009.845.82. 33. Characterization of Apple mosaic virus isolates detected in hazelnut in Poland. Cieślińska, M. and Valasevich, N. 2016, Journal of Plant Diseases and Protection. 10.1007/s41348-016-0021-4. 34. Hazelnut and Walnut Twig Borer, Oberea linearis L. (Coleoptera: Cerambycidae). Capinera, J. L., et al. 2008, Encyclopedia of Entomology. 35. The insect pest problem affecting hazelnut kernel quality in Turkey. Tuncer, C. et al. 2005. Acta Horticulturae. 9789066056886. 36. Halyomorpha halys, a serious threat for hazelnut in newly invaded areas. Bosco, L. et al. 2018, Journal of Pest Science. 10.1007/s10340-017-0937-x. 37. Distribution and damage caused by Halyomorpha halys in Italy. Bariselli, M. et al. 2016, EPPO Bulletin. 10.1111/ epp.12289. 38. Ecology and management of hazelnut pests. AliNiazee, M. T. 1998, Annual Review of Entomology. 10.1146/annurev. ento.43.1.395. 39. Biological control and morphological studies on nut weevil (Curculio nucum L. Col., Curculionidae). Akça, I. and Tuncer, C. 2005, Acta Horticulturae. 10.17660/actahortic.2005.686.57. 40. Incidence and severity of stink bugs damage on kernels in Turkish hazelnut orchards. Ak, K., et al. 2018. Acta Horticulturae. 10.17660/ActaHortic.2018.1226.62. 41. Ricerca applicata in corilicoltura. Sintesi dei risultati 2012. AA.VV. 2012, Regione Piemonte, p. 102. 42. Directive on Personal Protective Equipment «Sluzbeni Glasnik RS » number 36/09. 43. Directive on handling packaging of used plant protection products «Sluzbeni Glasnik RS» November 2015. 44. Law on Plant Protection Products «Sluzbeni Glasnik RS» 41/09 45. Effects of hot water treatments to control Xanthomonas arboricola pv. Corylina on hazelnut propagative material. Scortichini et al., 2016. Elsevier, Scientia Horticulturae 211 (2016) 187-193 46. Bacteria associated with hazelnut (Corylus avellana L.) decline are of two groups: Pseudomonas avellanae and strains resembling P. syringae pv. syringae. Pisetta M. et al., 2016.. Applied and Environmental microbilogy 68: 476-484.

NOTES