TOMATO - VIRUSES

EUROPEAN MOLE CRICKETS
Name of pest: Gryllotalpa gryllotalpa
Host range: Found in many habitats in loose, moist soil. It usually lives underground where it eats insects and roots. The female takes care of the eggs and cares for the young larvae, which is a unique feature among the crickets.
Occurrence and importance: The European mole cricket, Gryllotalpa gryllotalpa is widely distributed in the warmer areas of Europe and introduced in the US. It lives mainly in the ground where it feeds on soil invertebrates (e.g. earthworms and insect larvae) and on plant roots. It is usually of no or little significance as a pest and only a problem if it occurs in large numbers. Gryllotalpa gryllotalpa is classified as endangered or threatened in several European countries where it is now protected by law.
Symptoms:
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34. Figure Gryllotalpa gryllotalpa (European mole cricket); second, third- and fourth-instar nymphs and adult.

Source: Andreev R. & I. Manolov/Agricultural University, Plovdiv, Bulgaria

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35. Figure Sympthomes of Gryllotalpa gryllotalpa

Source: Vladimír Motyčka

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36. Figure Adult Gryllotalpa gryllotalpa

Source:L. Hunor

Mole crickets cause significant losses in vegetable production by feeding and tunnelling. They damage seedbeds and transplanted seedlings, causing water stress and eventual death. They also feed on roots, stems and leaves, damaging crops such as potato and radish. The feeding damage is cutworm-like, increasing the likelihood of other pathogen damage in seedlings. (Frank et al., 2004).
Description: Adult insects are 35-50 mm long, cylindrical, brown, and have a widened "mole foot" for digging.
Life cycle: Eggs are laid in underground chambers. The European mole cricket has enlarged forelegs and finger-like projections for burrowing in soil. Adults are 35-50 mm long, have short forewings, and have elongate hindwings. They burrow through soil, forming tunnels, and can fly in swarms at night. Females lay 100-300 eggs in chambers resembling hen's eggs, which hatch within 2-3 weeks. The nymphs leave to feed and develop independently, taking about a year in southern Europe and up to 18 months in cooler regions to reach sexual maturity.
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37. Figure Life cycle of Gryllotalpa gryllotalpa

Source: Shetlar, Ohio State University

Control: Estimating mole cricket populations involves soil surface tunnelling, soil flushing with dishwashing soap or synergized pyrethrin insecticide, soil washing apparatus, and sound traps for adult females.
Insecticides: Insecticides are commonly applied to soil to suppress mole crickets. Some applications require irrigation, as they must enter the root zone for effective results. Bait formulations, containing wheat bran, cottonseed meal, and 2-5% toxicant, are effective. Baits should be applied in the early evening and are incompatible with irrigation and rainfall.
Cultural practices: To avoid injury to vegetable transplants, larger plants are recommended. Crickets can invade crop land, so isolation or planting in large blocks is desirable. Maintaining turfgrass health is crucial for mole cricket management, including proper irrigation, fertilization, and mowing height. Identifying host plant resistance to mole crickets requires improvement in finer textured grasses, which may be tolerant of feeding or not preferred by crickets.
Biological control: The entomopathogenic nematode Steinernema scapterisci can enhance biological control of mole crickets. It is effective when applied to adults and can be used in low-parasitic areas. In a laboratory study, 0.3% azadirachtin applied once per week for 4 weeks led to 98% mortality and slower growth and tunneling compared to untreated crickets.

 


 

CLICK BEETLES, WIREWORMS
Name of pest: Click beetles, Wireworms, Elateridae
Host range: Click beetles are omnivorous pests that live in cropland or wood litter, feeding on cap mushrooms, garden plants, and tree roots. They attack grasses, ornamental plants, and cultivated plants, causing damage to young plants. Wireworms are destructive to many crops, including corn, small grains, and grasses.
Occurrence and importance: Wireworm larvae cause significant damage to field crops, consuming humus, roots, and germinating seeds. They can be difficult to control and can cause damage for years or the second year following sod planting.
Symptoms:
Image
38. Figure Elateridae

Source: A. Prosirov

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39. Figure Elateridae

Source: A. Prosirov

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40. Figure Sympthomes of Elateridae

Source: Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org

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41. Figure Sympthomes of Elateridae
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42. Figure Larvae and adults of Elateridae spp

Source: J. Saguez, CEROM

Click beetles are found in apple, pear, and tree fruits, chewing on flower buds, pistils, and stamens. They feed on roots and bore into plant bases, causing wilting and death. Serious infestations are usually localized to a single field or portions, reducing plant populations and causing withering and dying.
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44. Figure Distribution of Phthorimaea operculella

Source: EPPO Database (yellow: present)

Description of pest: Colour: Black, brown, or grey
There are 73 click beetles, known for their clicking noise-driven flight. These elongate, parallel-sided beetles are found in light or on flowers and can develop as larvae in soil or dead wood. Adult larvae are 28mm in size, have a brownish-black base, and have adapted to acne. They are hard-bodied, slender, cylindrical worms with yellow-to-brown legs and a notched last body segment.
Life cycle: Click beetles, also known as wireworms, have elongated bodies and six short legs. They lay eggs on leaves or near plant bases in soil. Adults swarm in summer and lay 50-100 eggs. In dry soil, eggs die, but hatch after 2-4 weeks in water. Adults live 10-12 months, while larvae migrate upward and downward depending on moisture. All stages and sizes of larvae can be found in the soil simultaneously.
Control: Understanding the lifestyle of Click beetles is crucial for developing a defence strategy. To prevent swarming, it is essential to dry out the soil and collect wireworm larvae from carrots and potatoes. Field spiders are sensitive to pheromone traps. In moderate or heavy infestations, treating seeds with insecticides, soil disinfection, and row treatments is justified. Microbiological agents and crop rotation are also essential.
Soil disinfectants should be applied at the end of summer and beginning of autumn. Wireworms can cause damage to corn, soybeans, and vegetables, and evaluating new fields for wireworm and grub problems is difficult. Proper drainage is crucial for certain species of wireworms. Soil insecticides are recommended for root vegetables, with liquid and granular options providing even coverage and good wireworm control.

 

POTATO TUBER MOTH (TUBERWORM)

Name of pest: Phthorimaea operculella (Zeller), Tecia solanivora (Povolny), Symmetrischema tangolias (Gyen)

The potato tuber moth (PTM) or tuber worm (PTW) appeared and spread in the United States in the last century. The butterfly consists of several species. Phthorinaea operculella, the most common and widely distributed form is found in North Africa and parts of Asia, Europe, America and Oceania, being the most widespread potato insect pest worldwide and most serious pest of potatoes in tropical and subtropical areas, but has also been found in traps at northern latitudes, which might indicate northward migration is due to global warming, mutation, etc. As it is not a good flyer, its migration is mainly caused by the movement of tubers.

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44. Figure Distribution of Phthorimaea operculella

Source: EPPO Database (yellow: present)

Host range: The potato tuberworm Phthorimaea operculella (Zeller), also known as potato tuber moth or tobacco splitworm, is an oligophagous pest (an insect feeding on a restricted range of food plants) of crops belonging to the family Solanaceae (mainly potatoes [Solanum tuberosum L.], tomatoes [Solanum lycopersicum L.], and tobacco [Nicotiana tabacum L.]).
Occurrence and importance: Potato tuberworm is a cosmopolitan pest. In addition to the United States it has been reported in Africa (Ethiopia, Egypt, Kenya), Asia (Iran, Syria), Europe, Americas (Latin America, Andes of Peru and Bolivia), and Oceania (Australia and New Zealand) in more than 90 countries. A very dangerous, fast-spreading, easily adaptable pest that is becoming a growing problem worldwide.
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45. Figure Sympthomes of Potato tuberworm

Source: Poveda, 2018. CABI Compendium Cc By-Nc 3.0 US

Symptoms:                 

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46. Figure Symptoms of Potato tuberworm

Source: Hanna Royals - Cc By-Nc 3.0 US

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47. Figure Adult Potato tuberworm

Source: Hanna Royals - Cc By-Nc 3.0 Us

PTM larvae can enter tubers through cracks in soil or eyes, or by laying eggs near the eye. They form tunnels, which do not heal and can lead to diseases like soft and dry rot. Most economic damage occurs in developing countries due to larval feeding, where caterpillars rapidly penetrate tubers, form galleries, and pupate on potato bags. Fungi, bacteria, and mites can develop inside the tunnels, causing tubers to rot and emit an unpleasant smell.
Description of pest: PTM/PTW has four stages: adult, egg, larva (damaging), pupa. Adults have a narrow, silver-grey body with greyish-brown wings patterned with small dark spots (pictured), with body length around 1cm and a wing span of 2.5 cm. It is mostly nocturnal and attracted to light. They are poor fliers. Eggs are oval, smooth and yellow, laid alone or in clusters on leaves or near eyes on infested tubers. Larvae, caterpillar-like (PTW, worm), are grey, cream or pale green with a dark brown head about half to three-quarter inch long in the final instar (pictured). Pupae are yellow or rust coloured; pupation occurs among dead leaves or debris, in soil, or on stored tubers.
Life cycle: Generation time is 17 to 125 days depending on temperature, commonly one month. Adult = up to 10 days; egg = 2 to 6 days; larva = 13 to 33 days; pupa = 6 to 29 days. Several generations per year, reproduction can continue in storage on tubers.
Adults can move up to 250 meters between plants to infest plants or tubers, with long-distance movement occurring when infected tubers are accidentally transported. The larvae lay 60 to 200 eggs, which hatch after five days. The larvae feed on their host plants for two weeks before pupating. The pupae are white, narrow, and 13 mm long, taking 10-30 days to fully develop.
Control: Monitoring potato tuber moth populations is crucial for effective timing control, and pheromone traps are essential in an integrated plant management (IPM) plan. Four traps are recommended for each quarter of the circle, with no ETL defined for crop damage or loss. Phthorimaea operculella is commonly controlled using pesticides, but resistance, resurgence, and potential adverse effects have led to integrated plant management strategies.
 
Cultural control is essential to prevent damage to weed and spontaneous flora. Deep planting, good seed coverage, and harvesting potatoes after fruit ripening are essential. Soil management and irrigation are essential, with proper watering and harvesting of tubers as soon as they are ripe.
Resistant varieties can help prevent pest infections and increase the effectiveness of other control methods. Biological control, such as parasitoids Copidosoma koehleri and Bracon gelechiae Ashmead, can be used as part of an IPM program and in organic farming. Bio-pesticides and natural chemicals, such as Bacillus thuringiensis (Bt) formulations, have proven effective for controlling potato tuber moths. Chemical control may be necessary if adults or larvae are present in large numbers. Storage management is crucial, with pheromone traps to monitor and remove damaged tubers and entry points to exclude moths.

TURNIP MOTH
Name of the pest: Agrotis segetum Commonly known as the common cutworm in English. 
The turnip moth, dirty roach or dust mite. Other names: black cutworm, common cutworm, cutworm, dark moth, dart moth, tobacco cutworm, Turnip dart moth
Host range: Turnip Moth has a very wide host range, covering in the order of 25 Families of plants.
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48. Figure Distribution of AGROTIS SEGETUM

Source: EPPO Database (yellow: present)

Occurrence and importance: Western, Southern Europe, Africa, Middle East, Mongolia, China, Japan, Hindustan, Nepal, Baltic States, Belarus, Ukraine, Moldova, Armenia, Azerbaijan, Georgia, Kazakhstan, Central Asia, Russia.
Female moths require nectar for oviposition, and their development depends on temperature and precipitation. Insect population density is influenced by entomophages and entomopathogens. Larvae feed on plantlets, causing damage to root collars and stems.
Symptoms: 
Image
49. Figure Adult AGROTIS SEGETUM,

Source: Chris Lewis

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50. Figure Adult Agrotis segetum

Source: © 2012-2023 Marion Friedrich

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51. Figure Larvae of A.segetum CABI (2022) ‘Agrotis segetum (turnip moth)’, CABI Compendium. CABI International.

Source: doi: 10.1079/cabicompendium.3797

Image
52. Figure larvae of A. segetum

Source: Abigal Gordon, 2020

A. segetum larvae cause transparent window panes when feeding on leaves, causing leaf drop, holes, or broken stems. Young larvae occurs at the root neck of the carrot and the crown will die. Confusion with other Agrotis species can complicate identification.

Life cycle: Imago larvae have a life span of 5 to 25 days, with a maximum of 40 days depending on temperature. They lay 400-1000 eggs and develop in 3 to 24 days. Larvae are greenish-gray to 5th instar, glossy dark-gray, and have dark stripes along dorsal and lateral sides. They overwinter in soil at a depth of 10-25 cm and pupate in soil at a depth of 1-6 cm. The pre-pupal stage lasts 2-10 days.

Control: Crop rotation, resistant variety cultivation, weed control, inter-row cultivation, early sowing, vetch-oat fallow, insecticide treatment, entomophage propagation, biological preparations, and monitoring using sex pheromone traps are essential for successful crop growth. For organic control NemaStar® Steinermena carpocapsae can be used.

 

 

SPIDER MITES
Pest name: Tetranychus urticae
Host range: Mites are common pests in all climate zones, feeding on many fruit trees, vines, berries, vegetables and ornamentals. Although they belong to the insect family, they are not insects, but arachnids. Spider mites, also known as web mites, are the most common mite pests and are among the most common pests in the garden and on the farm.
The common or two-spotted spider mite (Tetranychus urticae) is a pest that determines the protection of many horticultural crops. It is an extremely polyphagous species, its food plants include fruits (e.g. plums, apples), vegetables (e.g. cucumbers, melons, pumpkins, beans, peppers) and root vegetables as well.
Occurrence and importance: Web-forming spider mites include the Pacific spider mite, two-spotted spider mite, strawberry spider mite, and several other species. The most common are the closely related species belonging to the genus Tetranychus, which cannot be reliably distinguished in the field. However, there is little need for this, as their damage, biology and defenses against them are practically the same.
Symptoms:      
Image
53. Figure Tetranychus urticae

Source: Ralph E. Berry, Department of Entomology, Oregon State University, Corvallis, OR.2000.

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54. Figure Tetranychus urticae

Source: https://riverbendva.com/wp-content/uploads/two-spotted-spider-mite.jpg

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55. Figure Sympthomes of Tetranychus urticae
Source: https://riverbendva.com/wp-content/uploads/two-spotted-spider-mite.jpg
g
Spider mites cause chlorophyll loss, yellowing leaves, and deteriorating plants due to evaporation and puncture marks.
Description of pest: Mite species like goof mites, leaf mites, and spider mites are common in plants. They are well-adapted polyphagous species that prefer to eat multiple food plants. Accurate identification of pest species is difficult due to their size, and microscopic examinations are necessary for accurate analysis. Adult spider mites are about 0.5 mm in size, yellowish, and have two darker spots on their bodies. They reproduce in open fields and greenhouses and can cause damage in greenhouses and overheated apartments. The spider mite's tolerance allows it to overwinter in open fields and multiply again in a given culture.
Life cycle: Spider mites are simple insects with egg, larva, nymph, and adult stages. They reproduce rapidly in hot weather, preferring dusty conditions, and are susceptible to water stress. High populations may decline in late summer due to predators, host conditions, and cooler weather.
Control: 
Biological control
Spider mites face numerous natural enemies, including predatory mites like Galendromus occidentalis and Phytoseiulus, which are larger and more active. Other insects include six-spotted thrips, ladybird larvae, flies, and general predators like small pirate bugs and big-eyed bugs. Frankliniella occidentalis, a western flower thrip, can be an important predator but can cause severe damage to plants when not present. For organic control Naruralis-L, Beauveria bassiana (Balsamo) Vuillemin (Strain:ATCC 74040) as insect parasite fungus ca be applied.
Cultural Control
Cultural practices significantly impact spider mites. Regularly apply water to dusty areas, as water-stressed trees and plants are less tolerant. Provide adequate irrigation and mid-season washing to remove dust. Regular, forceful spraying of plants with water can reduce spider mite numbers, especially on leaves. If insecticidal soap or oil is needed, test on one or two plants to ensure it's not damaging. (See Chemical Control below.)
Chemical control
To effectively control weeds and maintain weed-free stock, avoid broad-spectrum insecticides and use acaricides (miticides) for mite infestations. Oil preparations are effective, and sulfur-containing plant protection products have mite-repelling effects. Proper spray coverage is crucial for proper effectiveness, as pests suck on leaf undersides.

 

THRIPS

Latin name: Thrips tabaci, Frankliniella occidentalis and other species
Host range: Thrips tabaci and F. occidentalis possess a very broad host range that includes many ornamentals, vegetable and weed species.
Occurrence and importance: F. occidentalis is very widespread in glasshouses and next to the direct damages that causes to plants, is a very efficient vector of Tomato spotted wilt virus.
Symptoms: Symptoms caused by thrips are usually hardly visible if the number of insects is small. If their population is more numerous, white (silver) spots on leaves and flowers occur. Highly infested parts of plants may die.

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56. Figure F. occidentalis,

Source:http://t3.gstatic.com/

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57. Figure Thrips tabaci,
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58. Figure Sympthoms of thrips

Source: Whitney Cranshaw, Colorado State University, Bugwood.org

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59. Figure Source of onion thrips

Source: https://extension.usu.edu/pests/research/onion-thrips

Description of the pest: Thrips are small insects with wings, yellow or light brown images, and wingless nymphae; identifying species is difficult without experience. 
Life cycle: Thrips hatch from eggs and undergo two larval stages, prepupa and pupa, before becoming adults. They lay eggs, drop to soil, or lodge in crevices or galls. Thrips have multiple generations per year and can complete their life cycle in just 2 weeks.
Control: Thrips are challenging to control, but an integrated program combining cultural practices, natural enemies, and effective insecticides can help. Monitoring thrips can be done by branch beating or shaking foliage or flowers. For thrips feeding in buds or shoot tips, clip off parts and shake vigorously. Hanging yellow sticky traps can also be used to monitor adult thrips. Control action is not necessary due to thrips' resistance to most insecticides. Blue sticky traps can be used for signalizing treatment and direct population reduction.


 

CARROT FLY

Name of pest: Carrot fly (Carrot rust fly) Chamaepsila rosae (syn. Psila rosae)
Host range: Carrot rust fly is a major pest of carrots, but parsnip, celery, and parsley may also be attacked. Umbelliferous herbs such as fennel, dill and angelica may harbour infection.

Image
60. Figure: Distribution of Chamaepsila rosae

Source: EPPO database

Occurrence and importance: Psila rosae is the most damaging pest of carrots, and it also attacks related plants such as parsley, parsnips and celery. Attacks on young plants can stunt their growth; attacks later in the season can allow secondary rots to develop which cause the carrot to decay in the soil or during storage. The yellowish-white larvae of this fly tunnel into roots creating mechanical damage and providing an entry for root rot pathogens.
Symptoms:
Image
61. Figure Sympthoms of Chamaepsila rosae
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62. Figure Larvae of Chamaepsila rosae
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63. Figure: Sympthoms of Chamaepsila rosae
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61. Figure Sympthoms of Chamaepsila rosae
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64. Figure: Sympthoms of Chamaepsila rosae
Image
65. Figure: Adult carrot fly

Source: https://insektarium.net/

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66. Figure: Adult carrot fly
Larvae tunnel below carrot root surface, causing rusty-brown discoloration, wilting, bulbous, forked, unmarketable plants, and root system damage. Common on parsnips and celery.
Description of pest: Small, shiny black or dark brown flies with yellowish legs and iridescent wings are preferred in hedges. Eggs are white, 0.5mm long, and laid near host plants. Legless larvae develop through three instars and are creamy white. They feed on taproots and pupate near the root, developing inside a barrel-shaped puparium.
Life cycle: Maggots are a rusty brown fly with two generations during summer, with damage occurring from June to July and August to October. They lay eggs in soil near plant bases and feed at the root tip. The first generation feeds from June to July, while the second generation feeds from late August into September. Adults hatch in September-October, mature in 4-6 weeks, and a second generation appears in late December, February, and May.
Control: To control carrot flies, practice crop rotation, remove culls and infected plants, choose less susceptible cultivars, sow sparsely, treat seeds with insecticides, use cultural control with chemicals, and avoid peak flights of adults during thinning young crops. Insecticides are usually necessary to produce clean crops in areas where the pest is prevalent.
Image
67. Figure: Covering with net

Source: https://laidbackgardener.com

APHIDS

 

Name of pest (Aphids on root vegetables):

Myzus persicae (Green peach aphid)

Myzus ornatus (Violet aphid)

Acyrthosiphon pisum (Pea aphid)

Aphis fabae (Bean aphid)

Cavariella aegopodii (Willow carrot aphid)

Cavariella pastinacae (Parsnip aphid)

Dysaphis crataegi (Hawthorn carrot aphid)

 

Host range: Host range depends on concrete aphid species. It including carrot, parsley, parsnip, other vegetables, fruit trees, field crops, etc.
Occurrence and importance: Aphids are responsible for important economic yield losses only sometimes, in special regions. Several aphids are virus vectors and this aspect of aphids’ damage often exceeds the loses by aphids feeding. Myzus persicae (Green peach aphid) is the most damaging aphid on many crops and it is prevalent as a vector of several important viruses.
Symptoms: Aphids attack leaves with yellow discoloration, leading to dryness and curling. They form galls, which contain numerous aphids throughout development. Aphids' feedings and toxic saliva damage plants, causing deformity, twisting, and gnarling. They weaken plants and produce sticky sugary waste, potentially causing mould development.
Description of pest: In general, aphids are small, soft-bodied, pear-shaped insects that have long antennae and a characteristic pair of cornicles (short tubes extending on either side of their abdomen). Their translucent bodies are most commonly green, brown, yellow or white, depends on species. There is description of some the most important aphid species below only:

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68. Figure M. persicea
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69. Figure: Aphid mummies have been parasitized by a beneficial wasp.

Source: https://www.ces.ncsu.edu/

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70. Figure Aphid nymphs look similar to the adults

Source:  University of Massachusetts Extension

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71. Figure A. fabae

Source: https://plantwiseplusknowledgebank.org

Myzus persicae eggs are elliptical, yellow or green, and black, deposited on Prunus spp. trees. Nymphs are greenish but yellowish, resembling viviparous adults. Winged green peach aphids have a black head, thorax, and yellowish green abdomen. They colonize plants and deposit young before taking flight.

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72. Figure Pea aphid

Acyrthosiphon pisum - the adults have narrow, dark bands at the tip of each antennal segment. The larvae are characteristically yellowish green in colour .

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73. Figure Pea aphid

Aphis fabae - Bean aphids are soft-bodied, pear-shaped insects with antennae and cornicles. They can be winged or wingless, with dark green to black bodies and white appendages. Nymphs are smaller than adults, with white spots on the abdomen.

Image
74. Figure A. fabae
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75. Figure Cavariella aegopodii

Source: project number: HU/02/B/F/PP-136012

Listo of Viruses:

  • IRIS YELLOW SPOT VIRUS [IYSV]

For more information on viruses, follow this link.

Listo of bacterial:
  • BACTERIAL SOFT ROT
  • BACTERIAL BROWN ROT
  • BACTERIAL RING ROT
For more information on the bacterium, follow this link.
Listo of fungi:
  • POWDERY MILDEW
  • SCLEROTONIA ROT
  • BOTRYTIS BLIGHT
  • VIOLET ROOT ROT
  • BLACK ROT
  • CERCOSPORA LEAF BLIGHT
  • PYTHIUM LEAF BLIGHT
  • CARROT ALTERNARIA LEAF BLIGHT 29
For more information on fungi, follow this link.
List of insects:
  • EUROPEAN MOLE CRICKETS
  • CLICK BEETLES, WIREWORMS
  • POTATO TUBER MOTH (TUBERWORM)
  • TURNIP MOTH
  • SPIDER MITES
  • THRIPS
  • CARROT FLY
  • APHIDS
For more information on insects, follow this link.
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