STONE FRUIT - PEST

In stone fruit orchards, the occurrence and damage caused by scale insects varies greatly depending on the variety and the season.

Host range: They feed on an immense number of host plants including plum peach, cherry, melon, berries, apple and ornamental trees, where they cause severe damage.

Occurrence and importance: Scale insects are quarantine pests and are widespread almost everywhere in the world, including Europe. The damage caused by the scale insects in stone fruit orchards has been decreasing, yet these pests cannot be completely eradicated. Even with effective control, some tree parts may be attacked again, due to the large number of host plants. Scale insect populations will increase rapidly in neglected domestic gardens as well as in commercial orchards. 

Symptoms: Scale insects regularly damage young shoots, fruits and leaves and leave 'spots' behind. The most widespread species is the San Jose scale; its feeding results in characteristic red spots. Heavy infestations result in yield losses and poor quality. They may kill the growing tip of the tree, parts of trees, or the entire tree. The larvae of the European fruit lecanium feed mainly on leaves. Their presence is indicated by pale spots.

Description of the pest: The European fruit lecanium and the plum scale have a single generation each year. They overwinter as L2 nymphs. By May, bright brown females of 2-4 mm length and with a bulging back develop from the overwintering yellowish-brown larvae and lay eggs. In June, the eggs hatch into larvae, which feed on leaves, shoots, branches and fruit for 2-3 months before hiding in woody parts as second instars and overwintering there. In Central Europe, the San Jose scale and the white peach scale have two generations. They overwinter as first instar nymphs or as fully grown females under the scales. The developmental cycle of the San Jose scale is more complex because males and females develop differently after the second instar nymph stage in April. The female remains under the scale, while the body of the male takes an elongated form. Adult males emerge in early May to fertilise the females. In early June, females produce 80-100 offspring by pseudo-vivipary. These grow their scales in a few hours and feed on the host plant. Humid, warm weather is optimal for reproduction. The development of the second generation of nymphs (summer generation) is similar and lasts until the first frost. Generations may overlap, so that almost all developmental stages may be present on the plant at the same time.

Control: Infected plant parts should be removed by pruning and burned to reduce pest populations to a minimum. It is very important keep to cultivation and sanitary rules, such as using healthy propagating material and developing a sparse, well-managed crown. Overwintering, mobile and immobile forms should be controlled by spraying. The emergence of the mobile forms of the plum scale and the European fruit lecanium may be forecast by 'dissecting' females under a magnifying glass or by placing vaseline rings in the canopy. The mobile forms of all the species are lemon-yellow and very small. The targeted control of flying males is based on forecasting.

For organic control Bacillus thuringiensis ssp. kurstaki, ABTS-351phylum

Host range: Aphids usually feed on a few specific plant species. They also need a host plant to reproduce. Host plants: peach, plum, Mahaleb cherry, sour cherry and other plum species (P. spinosa, P. tribona).

Occurrence and importance: Aphids are found all over the world. The most important problem caused by aphids that they transmit multiple viruses. Aphids multiply very rapidly in warm, wet springs, and are able to establish large colonies. As many as genealogies can develop in a single growing season.

Symptoms: Damage symptoms are quite similar. Aphid feeding on the leaves results in leaf twisting, deformation and bending. Leaves turn yellow, wilt and then drop. Nutrient loss increases and as a result the quality and quantity of the crop deteriorates. The honeydew produced by aphids favours the growth of sooty mould.

Life cycle: From overwintering eggs, only females hatch in early April. They are found in the flowers together with their parthenogenetic offspring. By early June, 2-3 generations will have developed. The last generation is composed of winged, viviparous females that reproduce by asexually. In most species, winged individuals colonise grasses (e.g. Veronica beccabunga, Galium aparine, Veronica longifolia, etc.) in the summer. At the end of summer, females very similar to the first generation, as well as males, develop and return to the host plant (peach, plum, cherry, sour cherry) where they mate and fertilised females lay overwintering eggs by the buds. The apricot aphid is about 2-2.5 mm long and pale green. It is probably the eggs that overwinter on apricot trees, as the first females are found on the trees very early on, at budburst. Later generations colonize the tips of shoots. They leave the young shoots of apricot in mid-September.

Control: There is a broad range of available agrotechnical control methods. The proper shaping of the crown, balanced nutrient supply, regular destruction of weeds and removal of infested leaves, shoot tips and branches create unfavourable conditions for colonies. For rational chemical control, it is essential to know the number of eggs, the time of emergence of the first females and the speed of reproduction.

For organic control orange oil, Melius oil and Phytocondi can be applied.

 

 

 

STONE FRUIT MITE

Casual organism: Aculus fockeui
Host range: peach, cherry, sour cherry, plum, almond.
Occurrence and importance:

Dry weather favours the increase of mite populations in late summer and autumn. In recent years, both aphids and mites have had to be actively controlled in stone fruit orchards. Their spreading of viruses increases their economic importance.

Symptoms: They cause damage by sucking on the leaves. As a result, transpiration increases, chlorophyll content decreases, the leaf laminae turn brown, yellow and lead-shiny miscolouration is typical. On young trees the twigs become broom-like whereas the leaves become spoon-like. Bud differentiation and fruit formation diminish.

Disease cycle: The fully developed female usually overwinters in a sheltered place at the base of the buds. Overwintering eggs have also been observed. The cylinder-shaped, 150-200 sized pest has difficult developmental process and more generations. The moving and sucking entities multiply in small number. Only in summer multiply they a masse. Over-multiplication can be observed mainly in dry, warm summers. At the beginning and middle of August the aphids occupy their overwintering place in a shelter closed by bud and twig.

Control: In IPM, dormant oils play an increasingly important role as they efficiently reduce initial populations, rendering later treatments more effective. Overwintering mites should be controlled in the spring. Increasing populations should be treated twice in the autumn. Sensible chemical control is based on a balanced nutrient supply, avoiding excessive nitrogen application. The presence and protection of predatory mites is also an important factor. For chemical control, rotation of active ingredients and application of specific acaricides that kill eggs, larvae and adults alike are useful.

Casual organism: Enarmonia formosana
Host range: apricot, cherry, sour cherry, almond, plum, peach, whitebeam. It rarely occurs on apple and pear.
Occurrence and importance: The cherry bark tortrix is widespread throughout Europe. It damages both young and mature trees. It is most often found in almond, but significant damage has also been reported from cherry and apricot. The cherry bark tortrix reproduces in the trunks and lower parts of the branches. Huge populations may cause the partial or complete dieback of trees.

 In the case of heavy infections, they also damage underground parts. Neglecting the scraping of trunks and dormant oil use in IPM increases the incidence of the pest, particularly in stone fruit orchards. Damaged areas are regularly colonised by secondary pathogens.

Symptoms: The caterpillars scoop irregularly shaped channels in the bark where intensive resin formation starts. Chewing may continue into the cortical tissue, causing serious nutrition and water transport disruption. The result is stagnation in growth, apex withering and branch necrosis. On the outer side of the bark small tubes occur covered with excreta granules. The tubes fall on the ground, around the stem, and these 'pupa shirts' provide a clear indication of infection.

In Central Europe the pest has two total or a third incomplete generations. The L5 stage larva population of the second generation overwinters under the bark, in the channels. The formation of pupae takes place in April while adult swarming can be observed in the first half of May. Development may take 25-30 days. The dark brown, slightly bronze, patterned moths are 7-9 mm in size. They lay their eggs one by one on the surface of the bark (40-180/female). The hatching caterpillars immediately enter the bark. After feeding and development they form cocoons. Adults emerge from the cocoons that stand out on the bark and start to form a new generation.

Control: As the cherry bark tortrix is rather a pest of orchards under IPM, do not replant such orchards with young trees. Chemical control is limited to the use of dormant oils. Application should be based on the monitoring of cocoons or pheromone trapping. When pruning, the bark and thicker parts of the branches should be thoroughly cleaned and wounds treated. The flight season is in the first half of May. The moth does not like to fly, so it can be killed from an orchard with a pheromone trap. This pest may be mechanically controlled by cleaning the trunk or by applying tree belts. Use Neem oil and Bacillus Thurengiensis spp. kurtaki ABTS-351 phylum in biologically managed orchards. Further possibility is the Isomate OFM Rooso Flex as a dispenser for mating disruption. 

 

 

 

Source: https://www.growveg.co.uk/pests/uk-and-europe/codling-moth/

Host range: plum, hawthorn, cherry, apricot, peach, very rarely walnut and apple.

Occurrence and importance: The pest is widespread in Europe and Asia. The plum fruit moth and the black plum sawfly together are the most dangerous pests of domestic and commercial orchards. Depending on the environmental conditions, the most damage is caused either by the overwintering or the summer generation. In productive orchards, severe infestations result in 15-30% fruit damage.

Symptoms: Fruit symptoms in late May and early June include 0.5 mm holes, oozing gum. Forced ripening turns fruits purple and they drop before the end of June. Second generation larvae cause similar symptoms in July, in this case the fruit is often mishappen. The caterpillar is inside the fruit and there is a lot of faeces near the plum stone. Infected fruit quickly drops and show symptoms of Monilinia infection, it starts to rotten. 
Life cycle: In Hungary, 3 generations develop a year^[1]. The moth overwinters as a fully grown larvae in a densely woven cocoon in cracks in the bark, in the root collar and rarely in the soil. The overwintering generation pupate in the cocoon in March and April. The flight season is continuous from late April to mid-June. The second generation emerges a little later, from June. Flight seasons often overlap. The caterpillars of the third generation reach full maturity in early September. The last instar is 10-12 mm long. The back is pinkish, the ventral side is lighter. The adult is 5 mm long, with a wingspan of 12-15 mm. Wings have a brownish grey pattern on a dark grey background. Eggs are spherical and 1 mm in diameter. The puparium is 5 mm long, brown.

Control: Effective control of the plum fruit moth should be based on sex pheromone trapping, a reliable and proven forecast method. The optimal time for control should be determined by observation and trapping.

Contact pyrethroids are effective against adults. Eggs and young caterpillars should be controlled by the application of growth regulators, bacterial preparations, phosphoric acid esters and neonicotinoids.

For organic control use Neem oil and Bacillus Thurengiensis spp. kurtaki ABTS-351 phylum in biologically managed orchards. Further possibility is the Isomate OFM Rooso Flex as a dispenser for mating disruption. 

Source: EPPO Database

Host range: peach, apricot, plum, almond, very rarely cherry and sour cherry.

Occurrence and importance: The pest occurs throughout Europe, Asia and North America. It is considered a particularly dangerous pest in some areas because of the increasing damage it causes. Its host plants and the symptoms it causes are very similar to those of the oriental fruit moth, so these two pests are easily confused. Damage in stone fruit orchards has recently decreased, but its presence in commercial orchards should be monitored nevertheless, as its flight season is random and long. In dry, warm weather the pest develops faster. In mild autumns, adult moths are still around in late October.

Life cycle: In Hungary, the peach twig borer has 2 generations, but rarely an incomplete third generation is also present if the weather is favourable in autumn. It overwinters as L3-L4 larvae within a tiny cell, called a hibernaculum, in limb crotches, covered by silk. It damages the buds occasionally. Overwintering caterpillars leave the hibernaculum, feed and then pupate in cocoons. The first flight season is in mid-May. Females lay single eggs on the underside of the upper leaves along the veins and on the fruit. The moths of the summer generation emerge in July. Egg-laying is more intense in their case. Larvae hatch after 5-10 days and damage the fruit. Moths of the autumn generation lay few eggs. The hatching larvae move under the bark and prepare the hibernaculum.

Control: Controlling the overwintering caterpillars is of paramount importance. The use of tree belts as a means of mechanical control to collect overwintering larvae is also efficient. Dormant oils kill significant numbers of overwintering larvae under the bark. In orchards under conventional management, insecticides should be applied between budburst and the white bud stage, according to the number of overwintering larvae as determined by monitoring. Omitted treatments may be made up for immediately after flowering. The control of later generations should be based on monitoring and pheromone trap catches. Masses of larvae will hatch 7-10 days after the highest number of flying adults was recorded. For organic control use Neem oil and Bacillus Thurengiensis spp. kurtaki ABTS-351 phylum in biologically managed orchards. Further possibility is the Isomate OFM Rooso Flex as a dispenser for mating disruption. 

Life cycle: The pest has 3-4 generations per year. A mixed population of the last 2 generations of fully grown caterpillars overwinters in densely woven cocoons in cracks in the bark. They often overwinter in quince fruits in groups. Larvae pupate in the spring. The first adults appear the end of April or beginning of May. Females lay about 15-200 eggs each (the number depends on the generation). Larvae hatch after 4-10 days of embryonic development. Eggs are laid on shoot tips, leaves and fruit. The second flight season in Hungary is expected in June, while the third one in mid to late July. The adults of the third generation will lay their eggs on or near the fruit, causing severe damage to the ripening fruit (e.g. Mariska, Dixired, Redhaven, Ford). Some of the fully grown caterpillars will move to the overwintering sites and form cocoons, while others will pupate. The adult is dark grey, 5-7 mm long, very similar to the red plum maggot. The eggs are 0.5-0.7 mm long and ashy grey. The larva is 10-14 mm long, yellowish white in colour, with a yellowish brown head and cervical shield with black spots. At this stage it is very similar to the caterpillar of Cydia funebrana.

Control: Do not plant stone fruit orchards near quince if possible, as the pest overwinters in large numbers in the fruit of quince. The most effective means of control is chemical treatment with growth inhibitors when the adults from overwintering larvae emerge. Practice has shown that treatment is best scheduled to 6-8 days after the start of the flight season. The treatment should be repeated within 10-14 days if the flight season is drawn out. The flight of moths may be monitored by pheromone traps. Control techniques and chemicals are similar to those applied for the peach twig borer, but multiple treatments are needed for effective control. In orchards under biological management, Bacillus thuringiensis spp. can be used effectively. Neem oil and Isomate OFM Rooso Flex as a dispenser for mating disruption can be used.

Symptoms: Larvae feed on the fruit, causing it to rot. The infested fruit drops and the larva pupates in the soil where it overwinters. The larva turns the flesh around the pit into pulp and contaminates it with its faeces. It leaves two holes on the fruit, a smaller one, where it enters after hatching from the egg, while the larger, round hole is where it leaves. The European cherry fruit fly damages early and medium varieties.

Life cycle: The pest has one generation a year. It overwinters as a pupa, 3-8 cm deep in the soil. Adults emerge in mid-April and the flight season lasts until early July. There is no relationship between emergence and plant phenological stages, so control technologies cannot be scheduled according to these. The female and the male are 4 mm and 3-3.5 mm long, respectively. The body is black, the front of the head is yellowish brown and the end of the thorax is yellow. The abdomen is 2-2.4 mm long and ends in an ovipositor. The wing pattern is very distinctive, with a diagonal stripe at the base and in the middle, while the wing tip has a V-shaped black stripe. The white eggs have a pointed tip. The last instar is yellowish white and 5-7 mm long. The puparium is straw yellow, egg-shaped and segmented. Adult females lay their eggs in the fruit flesh on days 5-10 days after emerging, when fruits start to turn red at on the uppermost fruits as they fly towards light. Embryonic development takes 5-10 days. It takes 10-15 days to reach full development. Last instars leave the fruit (they simply drop to the ground) and pupate in the soil. Diapause may play an important role in the life cycle of the species, as some of the pupae (up to 10-15%) that overwinter in the soil do not release adults in the spring, but remain in the soil for another year, with adults only emerging in the following spring.

Control: Tillage is not effective against the pest, though it overwinters in the soil and is prone to diapause. Timely harvesting can effectively reduce the number of pupae preparing for overwintering. In private and commercial orchards, the flight season may be efficiently monitored by yellow sticky traps. In isolated gardens the traps may also be used to eradicate the pest as adults do not fly long distances.

Using the traps, the peak of the flight season may be forecast and the number of individuals reduced. 2-3 chemical treatments are necessary due to drawn out swarming, the long lifespan of adults and continuous egg laying.

Innovative solution may be the calcined kaolin which scares off flies and causes meeting confusion.

It is very important to consider the maturation period of the varieties. The possible multiple action of the products may also be used effectively against other pests (aphids, scale insects).

Source: B. Ö. Çatal, M. Ulusoy 2018.

Host range: The most important hosts are cherry and sour cherry, but it may also damage wild cherry, mahaleb cherry, Lonicera tatarica and Lonicera xylosteum. 

Occurrence and importance: The pest is widespread throughout Europe. It is a common pest of sour cherry and cherry. The insect has one generation. It is a member of the fruit fly family and can cause enormous damage in orchards where microclimatic conditions are favourable and the area is not properly managed. In such cases, the damage can be as high as 50-100%.

Symptoms: Larvae feed on the fruit, causing it to rot. In one fruit, several larvae may be found. As infestation progresses, sunken spots appear, the pulp turns brown and the fruit ripens early or drops and the larvae pupate in the soil where it overwinters.

Life cycle: The eastern cherry fruit fly has one generation a year. It overwinters as a pupa, 3-8 cm deep in the soil. Adults emerge later than those of the European cherry fruit fly and the flight season is a month longer. The flies are 4–5 mm long. They are black with yellow margins on the thorax. The scutellum is white, the tibiae and tarsi are yellowish, and there are transverse and oblique blackish markings on the wings. The eastern cherry fruit fly has four white crossbands on the abdomen.

Control: Tillage is not effective against the pest, though it overwinters in the soil and is prone to diapause. Timely harvesting can effectively reduce the number of pupae preparing for overwintering. In private and commercial orchards, the flight season may be efficiently monitored by yellow sticky traps. In isolated gardens the traps may also be used to eradicate the pest as adults do not fly long distances.

Using the traps, the peak of the flight season may be forecast and the number of individuals reduced. 2-3 chemical treatments are necessary due to drawn out swarming, the long lifespan of adults and continuous egg laying. Spraying large droplets of Combi-Protect attractant combined with the insecticide acetamiprid is an effective method of control. Innovative solution may be the calcined kaolin which scares off flies and causes meeting confusion.

 

 

 

Host range: Cherry, sour cherry and fruits in general. Fruit remaining on the trees until the end of September e.g. in the case of delayed harvest are attacked by the maggots. It has several generations and drawn out flight seasons. The first and the second generations attack late cherry and sour cherry varieties. Yellow traps catch it as late as in mid-August. Eggs overwinters in quince fruits. Overwintering eggs are laid in batches into fruits, whereas in the vegetational season, females lay single eggs.

Occurrence and importance: This Mediterranean pest occurs everywhere in Central Europe as a result of the climate change. Outbreaks can be expected during dry spells. Its numbers are not reduced by extreme drought. It is continuously present in unharvested sour cherry and cherry.

Symptoms: Maggots feed on the pulp of fruits and cause premature dropping. The attacked fruits decay because of secondary infections.

Life cycle: The pest has one generation a year. It overwinters as a pupa, 3-9 cm deep in the soil. Adults emerge in mid-April and the flight season lasts until early July. Eggs are deposited under the skin of fruit which is just beginning to ripen. Several females may use the same fruit. Adult flies are 3-5 mm long. The body is light brown. The wings are mottled with distinct brown bands extending to the wing tips. The abdomen is brown, encircled by two light-coloured rings. The thorax (middle) has irregular patches of black and silver, giving it a mosaic appearance. Eggs are spindle shaped. Third instars are 8-9 mm long. Pupae resemble a small reddish brown capsule about 4mm long.

Control: Tillage is not effective against the pest, though it overwinters in the soil and is prone to diapause. Timely harvesting can effectively reduce the number of pupae preparing for overwintering. In private and commercial orchards, the flight season may be efficiently monitored by yellow sticky traps, but only when combined with attractants. Using the traps, the peak of the flight season may be forecast and the number of individuals reduced. 2-3 chemical treatments are necessary due to drawn out swarming, the long lifespan of adults and continuous egg laying. Spraying large droplets of Combi-Protect attractant combined with the insecticide acetamiprid is an effective method of control.

Innovative solution may be the calcined kaolin which scares off flies and causes meeting confusion.

 

Host range: All berries and stone fruits as well as grapes. The pest has many generations. The first generations feed on berries, while latter ones prefer stone fruits and grapes. Adults lay multiple eggs in in a single fruit. The feeding of larvae causes the rotting of fruit. Females prefer fruits at the beginning f ripening to lay their eggs, using their saw-toothed ovipositor which is able to pierce even thick-skinned cherry varieties. In vineyards, adults may be found even after the first ground frosts. The pest is present in very high numbers in grapes. It can be distinguished from other Drosophila species by the spot on its wing tips. The species overwinters in cracks in the bark and fallen fruit.

Occurrence and importance: With the climate change, the pest has invaded the entire territory of Hungary and has regular outbreaks. During periods of extreme drought, they are increasingly motivated to find juicy fruit to ensure the survival of the species. Because individuals are present in very high numbers in a single fruit and the pest damages almost all fruits, the economic damage caused is significant.

Symptoms: Females lay their eggs in fruit beginning to ripen. The wound made by the ovipositor is clearly visible. Larvae feed in groups and their feeding opens the way to rots and Bothrytis.

Life cycle: The pest has seven to eight generations a year. It overwinters in adult or pupa in the soil or mummified fruit dropped to the soil. Females overwinter in sheltered, frost-free woodland environments or in orchards, possibly in barns. It is not yet fully known where exactly they overwinter. Compost heaps also appear to be suitable. 

Females may lay up to 400 eggs into semi-ripen fruit. The eggs hatch after 20-30 hours at 20-25 °C and the larvae immediately start chewing the flesh. The life cycle of the spotted wing drosophila is about 10 days at 25 °C lasts.

The species needs starch and compost contains it, which explains why the pest is found in such high numbers around compost heaps.

Control: Densely placed traps containing fermented sugar may be used to monitor the flight season. Control methods should be applied when the first adults appear. Chemical control should be applied again near the peak of the flight season. The active substance that may be used is Cyazypyr and all its forms for disinfecting the soil or as foliar spray. Pyrethroids kill flying individuals, but their use is limited. In commercial greenhouses, early infestations are controlled by insect nets. These are nor moved, instead, staff enter the greenhouse through a double airlock. Fruit residues should be destroyed and must not be discarded on compost heaps.

Host range: all weeds and cultivated plants and roadside shrubs.

Occurrence and importance: The polyphagous horticultural pest feeds on almost everything. It is often found on roadside weeds and all cultivated vegetables and fruits. Nymphs develop under a white waxy fluff which hinders assimilation by green surfaces. Feeding inhibits shoot growth as both the adult and the nymphs have piercing-sucking mouth parts. They also act as virus vectors and can completely destroy the attacked plant; afterwards they migrate to another host. They were introduced in Hungary by imported propagules.

Symptoms: Nymphs overwinter in the fluff, which may be mistaken for the mycelium of some fungal pest. The nymphs resemble aphids and feed under the fluff. he adult adult is a cicada that looks like a grey moth with red eyes.

Life cycle: Females lay their eggs on the bark of woody plants in autumn. It is the eggs that overwinter. Hatching depends on the temperature (May/June). Damage to shoots and leaves is expected from the end of May. Nymphs develop by sucking on leaves and shoots for 2-3 months. The species has five nymphal stages. Their shed skin and the white wax fibres and granules covering their bodies forming a distinct, lime-like layer on the plants (Fig. 2). In Hungary, adults appear from mid-July and feed on plant shoots. Adults flee when disturbed. In Hungary, one generation develops. They are extremely polyphagous, with hundreds of known hosts (mostly woody plants, but also some herbaceous species). They are caught by forestry light traps.

Control: As a preventative measure, clear the bark of woody plants to reduce the chance of overwintering. At the end of winter, dormant oils may reduce the number of overwintering eggs. Alkaline preparations have a repellent effect and the change in pH within the plant results in an unpleasant taste, making mobile forms leave the damaged woody plants.

Hosts: All fruits and vegetables, arable crops. If the bugs cannot find a crop they prefer, they can also survive on weeds. Outbreaks are also possible.

 

Occurrence and importance: The pest is present in America and Europe. Outbreaks were first observed in autumn-harvested fruit and vegetables, but the biggest surprise was the mass emergence of the overwintering individuals. As the pest has piercing-sucking mouthparts, it serves as a vector of viruses. Having many hosts, indirect damage may be expected in both fruit and vegetable stands. It is a difficult species to eradicate.

Description: The adult bug is 12-17 mm long. The back is greyish brown with some reddish hues, decorated by black spots forming an irregular pattern and sometimes merging, giving the adult a 'marbled' appearance. The antennae are dark, with a pale yellow ring at the base and tip of the fourth joint and at the base of the fifth joint (important for identification). The back shows a distinctive black and white banding around the outer edge of the abdomen. The forewings are colourless, with some brown or grey veins, these sections appearing as longitudinal dark bands. The ventral side of the abdomen is light yellow, with black spots in the lateral third. The legs are pale reddish yellow, with most of the thigh and leg covered by black spots.

Symptoms: The bug spreads stylet borne viruses. Little is known about the symptoms on different plants, but due to the regular outbreaks, it is noteworthy to observe the pest's life cycle and pattern of emergences.

Control: Control should be based on monitoring the emergence of the pest by means of light traps and funnel traps. At the moment, there are not any registered chemical products against this pest in Hungary. For biological control, Trissolcus japonicus and parasitoid wasps (Trissolcus basalis) can be considered.

Source: https://www.wikiwand.com/fr/Heteroptera

Stunted growth, mosaic mottling, distorted leaves and fruits (the latter with wrinkles and chlorotic or necrotic spots), reduced fruit size and the abortion of flowers have also been reported.

Transmission & Epidemiology: PVY is transmitted in a non-persistent manner, by at least 25 aphid species. Its most efficient vector is Myzus persicae (the green peach aphid), which colonises peppers. As Myzus persicae is able to retain the virus for more than 6 days.

Control:

• Remove/ destroy potato crops after the final harvest in order to minimise PYV spread to new crops.
• Destroy volunteer plants before planting to reduce PYV inoculum and aphid populations
• PYV-resistant varieties

 

Throughout insect vectors:

• protect hotbeds with nets to prevent early infection
• use coloured sticky traps to monitor vector populations
• control of the vector population by chemical, biological and/or integrated means
• oils

 

  

CUCUMBER MOSAIC VIRUS

Pathogen: Cucumber mosaic virus (CMV)
Host range: CMV has a very wide host range that includes more than 1000 plant species
Distribution: worldwide

Importance: CMV causes severe damage during flowering and in the yield. Its impact depends on the geographical area. Although it is distributed worldwide, the most significant losses are experienced under warm climates.

Symptoms: Young leaves often display a light-yellowish green mosaic mottling, which may develop into diffuse chlorotic lesions. Leaves get distorted, with curled main veins. On old leaves, chlorotic and/or necrotic concentric rings may appear, as well as irregular spots.

Fruit symptoms include reduced size, dark green spots, irregular ripening and/or sunken lesions with necrotic centres. The extent and severity of CMV symptoms is significantly affected by the age of the plant at the time of infection. When infected young, plants typically develop severe symptoms, including mosaic mottling, small and deformed leaves and reduced fruit size. In some cases, the disease may destroy the entire crop.

Transmission & Epidemiology: CMV is transmitted in a non-persistent manner by more than 86 aphid species. Myzus persicae (the green peach aphid) and Aphis gossypii (the cotton aphid) are two of the most efficient vectors.

CMV may also be transmitted by seeds.

 

Control:

Use virus-free propagative material (seeds, etc.)

Control of weed reservoir hosts

• eliminate weeds in the vicinity of the crop
• remove and destroy infected plants.

Chemical control of aphids

• protect hotbeds with nets to prevent early infection
• use coloured sticky traps to monitor the vector
• control of the vector population: chemical, biological and/or integrated control

Resistance breeding

The most effective methods of control are growing resistant varieties.

 

 

ALFALFA MOSAIC VIRUS

Pathogen: Alfalfa mosaic virus (AMV)
Host range: AMV infects a wide range of hosts, with about 600 species in 70 families being susceptible. Occasionally it may infect woody species.
Distribution:

Importance: Worldwide occurrence, commonly it does not cause economically significant damage, but in some cases, it may significantly reduce yields.

Symptoms: The bright yellow mosaic mottling on young leaves and their increasingly severe distortion are easily confused with the symptoms of other viruses.
On fully developed leaves, characteristic AMV symptoms may be observed including white blotches arranged in a mosaic pattern. In the summer, these symptoms are less important.
Fruits may be distorted and reduced in size and develop necrotic spots. These symptoms are particularly pronounced in the late cultivars.

Transmission & Epidemiology: AMV is transmitted in a non-persistent manner by aphids such as Myzus persicae Sulz. It may also be transmitted mechanically or by Cuscuta species in the field.

Control: 
Reduce viral inoculum levels:

• eliminate weeds in the vicinity of the crop
• remove and destroy infected plants.

 

Vector control to minimise transmission:

• protect hotbeds with nets to prevent early infection
• use of coloured sticky traps to monitor the vector
• control of the vector population: chemical, biological and/or integrated control

Produce virus-free seeds (e.g., seed treatment)

Isolation from other hosts (pepper, tobacco, peas etc.)

 

 

CAPSICUM CHLOROSIS VIRUS

Pathogen:   Capsicum Chlorosis virus (CaCV). It is a tospovirus (prototype TSWV), a member of the genus Orthotospovirus (family Tospoviridae) only identified on the island of Crete in EU (Greece) (EFSA Panel on Plant Health (PLH), et al. 2022).
Host range: CaCV infects plant species in the family Solanaceae (i.e. pepper, tomato) and ornamental plants.
Importance: Trade of plants (excluding seeds), ornamental plants, cut flowers, fruits and movement of soil and machinery contribute to further spread of the virus and/or viruliferous thrips to larger distances.
Symptoms:  CaCV can induce severe symptoms on its hosts, mainly on leaves and fruits. Main symptoms are:  frequently consisting of chlorosis, mottle. The young leaves show chlorosis, curling and deformation, whereas chlorosis, ringspot and line patterns develop on old leaves.

Transmission & Epidemiology: CaCV is transmitted in a persistent manner by thrips (similarly to TSWV).

Control:

Preventive measures should be applied to hinder thrips-transmission (similarly to TSWV).

 

TOMATO MOSAIC VIRUS

 

Pathogen:  Tomato mosaic virus (ToMV). It is an important member of the genus Tobamovirus.
Host range: The host range of ToMV is very wide (similarly to TMV).
Importance: ToMV has been reported from countries where tobacco, tomatoes or peppers are grown. ToMV is of greater economic importance than TMV and mostly damages greenhouse crops.
Symptom: Its most typical symptoms include mosaic mottling, deformed leaves, necrotic lesions and stunted growth.
The symptoms of ToMV are similar to those of TMV, but more intense, including dark greyish-brown stripes on the stems and branches, followed by the necrosis of the foliage and defoliation.
Transmission & Epidemiology: ToMV (similarly to TMV) is transmitted mechanically, by contact between healthy and infected plants or contaminated objects, similar to the transmission of TMV.
It is also transmitted by seeds in the case of certain members of the family Solanaceae.
It stays infective in plant debris and on contaminated objects for a very long time (persistent).
It may also be transmitted by Cuscuta species. 

Control: 
Preventive measures should be applied to hinder transmission.

• use healthy seeds
• disinfect tools
• isolate crops, remove and destroy infected plants
• use ToMV-resistant varieties

 

 

CANDIDATUS PHYTOPLASMA SOLANI (PEPPER STOLBUR)

 

Pathogen: Candidatus Phytoplasma solani (Stolbur phytoplasma)
Host range: Stolbur is able to infect practically any solanaceous plant and has also been found in sugar beet and field bindweed.
Distribution:

Importance: Stolbur regularly damage crops in droughty years in southern, eastern and central Europe. There is no chemical method available to control it.

Symptoms: The most important symptoms are the reddish discolouration of green parts, upward rolling of leaves, yellowing and defoliation. Flowers are malformed, have green petals and may develop into leaves. The disease urges the development of numerous shoots while stunting growth. The plant does not produce fruit or fruits are deformed.

Transmission & Epidemiology: Stolbur overwinters on perennial weeds, especially in the rhizomes of the field bindweed (Convolvulus arvensis). Its vector is the cicada Hyalesthes obsoletus (sometimes other cicada species, too). The insects pick up the disease when sucking on infected plants.

Stolbur is transmitted in a persistent manner. Infected cicadas, flying from plant-to-plant actively spread the disease during the summer. The incubation period of stolbur is long, so usually it is first detected in pepper fields in the late summer. Its vector is polyphagous and thus infects further bindweed specimens, promoting the persistence of the pathogen.

Control:

Proper weed control is of paramount importance, not only on the field itself, but also in its surroundings. Take special care to eliminate field bindweed.

There is no stolbur resistant cultivar. Dealers and distributors may say otherwise, but this is misleading.

Monitor the insects in the crop. When cicadas are spotted (they are difficult to find unless they jump or fly right in front of your eyes), precautions should be taken.