Pupa — The white, mm-long pupae darken gradually beginning with the eyes. Distribution — Blister beetles are found throughout the continental United States and agricultural areas of Canada. Although fairly common in North Carolina, they are infrequently pests of importance.
Host Plants — Blister beetles have a wide host range. Important vegetable hosts include potato, tomato, melon, eggplant, sweet potato, bean, pea, cowpea, pumpkin, onion, spinach, beet, carrot, pepper, radish, corn, and cabbage. Damage — Some species of blister beetles feed on flowers but most species are strictly foliage feeders. This latter group feeds gregariously, occasionally damaging foliage and stunting plant growth.
Black stringy excrement often is found on heavily infested plants. Blister beetles also have been known to transmit the disease organism which causes southern bacterial wilt of potatoes.
Larvae, on the other hand, are considered beneficial insects because they feed on grasshopper eggs. Life History — Blister beetles have an unusual life cycle. They usually overwinter as sixth instar larvae 2. In spring, resting larvae molt into active nonfeeding larvae which soon pupate. Adult blister beetles begin to emerge in June. Adults can be found well into September but are most abundant in July. During summer months, they congregate and feed voraciously on foliage or flowers depending upon the particular species of beetle.
Two to 3 weeks after mating, each female deposits up to six egg masses in the soil. These masses may contain 50 to eggs apiece. A few days after locating and feeding on the eggs, the active larvae molt and become fairly inactive.
The grubs continue to feed on the eggs and molt until they are fat, almost legless fifth instars. These larvae create oval hibernating chambers in the soil, molt into sixth instars, and overwinter. Development usually continues the following spring but the larvae may remain inactive for as long as two years. Sometimes fifth instars molt directly into the pupal stage, by-passing the last two larval instars.
As a general rule, however, blister beetles complete one generation each year. Blister beetles often appear suddenly and may cause much damage before they are detected. Therefore, insecticides are generally applied as an emergency measure after beetles are found on a crop. Control failures usually are attributed to applying insecticides too sparingly, too late. Spot treatment is usually adequate. For recommended insecticides and rates, consult the current North Carolina Agricultural Chemicals Manual.
Adult — This oval, convex beetle is yellowish-brown and about 9 to 14 mm long. It has five longitudinal black stripes on each wing cover and a variable number of black spots on the pronotum area just behind the head. Egg — The yellow or orange elongated eggs are deposited on end and grouped into rows Figure KK. Each egg is about 1. Larva — Red at first, this soft grub has a black head and black legs. As it matures, the larva turns yellowish-red or orange and develops two rows of black spots along each side of the body.
It reaches a length of about 10 mm. Pupa — Generally resembling the adult in shape, the pupa is approximately 13 mm long. Distribution — The Colorado potato beetle can be found throughout most of North America. Host Plants — Colorado potato beetles infest a wide variety of plants including tomato, potato, eggplant, pepper, tobacco, ground cherry, nightshade, and other solanaceous plants. Damage — Adult beetles and larvae feed on leaves and terminal growth of their host plants.
The loss of foliage hinders development of tubers or fruit thereby reducing yield. In cases of heavy infestation, entire plants may be killed. Colorado potato beetle damage often occurs in isolated spots throughout the field. Life History — Colorado potato beetles overwinter as adults in the soil. After emerging in spring, beetles feed for a short period before mating and laying eggs. Females each deposit to eggs in clusters of 20 or more on the undersides of leaves.
Four to 9 days later, larvae emerge and feed for the next 3 weeks. Once mature, larvae drop to the ground and pupate in the soil. Five to 10 days later, a new generation of beetles emerge. In North Carolina, at least two full generations and a partial third occur each year.
Many cultural enemies help keep Colorado potato beetle populations low. Birds feed upon adults and larvae while predatory bugs attack eggs and larvae.
These predatory bugs may be gray, brown, or brightly colored and are often shield-shaped. Two kinds of gray and black tachinid flies also parasitize larvae. Katahdin potatoes show some resistance to Colorado potato beetles. Early treatment of commercially grown potatoes with systemic insecticides normally control overwintering beetles and early hatching larvae. However, some insect activity may persist around the field. The application of a foliar insecticide is not recommended until the first eggs have hatched.
As soon as damage is noticed, treatment should begin. Chemical control is directed toward the first generation since the buildup of subsequent generations may cause severe damage and defoliation. In some cases, spot treatments may be effective. Adult — The potato flea beetle is about 2. The equally small tobacco flea beetle is yellowish-brown with a dark band across the wings. Varying from 2. Larva — The slender cylindrical grub has a whitish body, a brown head, and 3 pairs of tiny legs near its head.
Potato and tobacco flea beetle larvae are 4 to 5 mm long when fully grown. The mature larva of the palestriped species is slightly longer than 6 mm. Pupa — The white pupa roughly resembles the adult in size and shape. As it matures, it darkens gradually. Distribution — The potato flea beetle occurs from Maine into the Carolinas and westward into Nebraska. Although the tobacco flea beetle is fairly generally distributed, it is primarily a problem in the South.
The palestriped flea beetle occurs in most areas of this country, its northern limits lying in Utah, Colorado, Idaho, and New York. Host Plants — Potato and tobacco flea beetles infest solanaceous plants such as tomato, potato, tobacco, pepper, horsenettle, etc.
The palestriped flea beetle, however, is a more general feeder. Its hosts include potato, corn, eggplant, tomato, pea, bean, watermelon, pumpkin, sweet potato, peanut, oat, cotton, grape, pear, and strawberry. Damge — Flea beetles attack the foliage leaving small round holes.
Most serious early in the growing season, this injury eventually kills infested leaves. In addition, potato flea beetles may transmit early blight. As a general rule, flea beetles are much less of a problem on potato than on other solanaceous crops. Life History — Flea beetles overwinter as adults among debris in or near fields of host plants. They resume activity in spring and feed on weedy hosts until crop hosts are available.
Eggs, deposited in soil near the bases of host plants, may require a week or more to hatch. Grubs feed on or in roots, tubers, and lower stems for 3 to 4 weeks before pupating. After a pupal period of 7 to 10 days, a new generation of beetles emerges.
The palestriped flea beetle completes only one generation each year. Potato and tobacco flea beetles produce three to four annual generations in North Carolina. Cultural methods are primary sources of defense against flea beetle infestations.
First, it is important to keep fields free of weeds. Destruction of plant residues, especially piles of cull potatoes and trash where beetles hibernate, prevents the buildup of high populations.
Late planting favors growth of the host plant over establishment of flea beetles. Lastly, covering beds of seedlings with a gauze-like material prevents beetle entry. A number of insecticides granular and foliar are available to control adult flea beetles. On potatoes, an in-furrow insecticide application at planting can prevent flea beetle damage early in the season. For control throughout the season on all vegetable crops, spray plants when adults appear and repeat as needed.
Flea beetles. Deep tilling exposes white grubs to adverse environmental conditions such as sunlight and frost, and to predatory vertebrates. Ensuring proper drainage in the field will reduce white grub populations since they prefer moist soil, especially with high content of decaying organic matter.
Crop rotation is an effective control method when potato is rotated with resistant or less susceptible crops, such as deep-rooted legumes e. Strips of African marigold Tagetes sp.
Allium crops also repel adult beetles from laying eggs Larrain et al. Natural enemies that control white grubs include parasitic wasps in the genera Tiphia, Myzinum Hymenoptera: Tiphiidae , and Pelecinus polyturator Drury Hymenoptera: Pelecinidae , and the fly, Pyrgota undata Wiedemann Diptera: Pyrgotidae. Spores of the pathogens Bacillus popilliae , B. Nematodes species such as Steinernema sp.
This pest is not easily controlled with insecticides. Chemical treatment on grubs must be done when they are young, as older larvae are more robust and move to a greater depth as they develop Gupta and Gavkare Tetranychus urticae C. Koch, T. Tetranychus urticae feeding on a potato leaf a , and symptoms of white mite feeding causing deformation of buds and tender leaves b and toasted appearance on the underside of a potato leaf c. Mites are polyphagous. Major hosts are potato, tomato, tobacco, pepper, eggplant, pumpkins and squashes Cucurbita pepo L.
Hazzard ; Landis and Davis ; Goftishu et al. Mites are extremely small, almost microscopic, and feed on the cellular matter of leaves. Chlorotic spots caused by mites give leaves a tan coloring, whereas high infestation will cause leaf and plant wilting. Damage to growing plants is particularly severe. The white mite colonies are located on the underside of the young leaves and on the buds. The infested plants take a dark to moderate green coloration and develop a somewhat leathery appearance.
Heavy infestation may result in plant death CIP ; Larrain et al. Plants with severe damage of P. When infestations occur in an intense and violent way they can cause the destruction of entire crop field. In the same way, attack by hundreds or thousands of red spider mites can cause thousands of lesions, thus can significantly reduce the photosynthetic capability of plants CIP ; Larrain et al. Mite infestations normally begin at boundaries of the potato fields especially those neighboring fields of preferred host plants such as maize, alfalfa, and mint.
Stressed potato plants tend to be more susceptible. Constant visual monitoring and early detection is key. Check on the underside of leaves that show symptoms of nutrient deficiency CABI g , h. Natural control. Often mites are kept under control by their natural enemies, including predatory thrips, lacewings, gall midges Feltiella acarisuga Vallot and ladybird beetles Stethorus punctillum Weise and predatory mites Phytoseiulus persimilis Athias-Henriot, Neoseiulus californicus McGregor , Amblyseius andersonii Berlese, Galendromus occidentalis Nesbitt, Mesoseiulus longipes , and Hypoaspis miles Berlese Pundt Mites become primary pest when natural enemies are destroyed by insecticide applications to control other insect pests.
So, avoid use of nonselective pesticides which reduce predatory mite populations. Plant extracts such as azadirachtin neem oil , or from cotton seed, soybean, clover, garlic, rosemary Rosemarinus officinalis L. In some cases, focal treatments are recommended using either soap, sulphur, Bifenazate, abamectin, spirotetramat, and spiromesifen Hazzard Pale or brown nymphs and darker adults of Frankliniella occidentalis on the underside of potato leaves a , and symptoms of thrips feeding causes silvering on underside of a potato leaf b.
Thrips can cause major damage mainly during dry climatic conditions. Because of heavy feeding, potato leaves develop a silver or chlorotic dotting of the tissues and become deformed. Thrips are minor pest of potato. The virus reduces crop yield and tuber quality CABI i , j. Thrips feed on a wide range of plants, including weeds from which they can invade potato crops. Therefore, weed control is a good management strategy for this pest. Susceptible crops onion, tomato, corn, artichoke, and pumpkin should not be planted next to a potato crop.
Behavioral control. Yellow or blue especially for F. Various species of the worldwide anthocorid genus Orius are used in biological control against thrips, and these bugs are important as predators in many natural populations. Amblyseius swirskii Athias-Henriot and Neoseiulus cucumeris Oudemans are two of the most widely used predatory mites in the biological control of F.
Fungal pathogens and nematodes, such as Beauveria bassiana and Steinernema feltiae , are also being used commercially. Low to medium toxicity pesticides used against thrips include Spinosad, Spinetoram, and Abamectin Bentley and Rice Tuta absoluta Meyrick Lepidoptera: Gelechiidae. Adult of Tuta absoluta a , larvae infestation on potato leaf b , and tuber c.
Hosts of T. Other cultivated host plants are slender amaranth Amaranthus viridis L. Noncultivated Solanaceae hosts include a wide range of weeds such as Lycopersicon hirsutum Dunal, Lycopersicum puberulum Ph, Solanum americanum Mill.
On potato, T. Foliar damage is a result of mine-formation within the mesophyll by the feeding larvae. The newly emerged larvae are quite mobile and begin their feeding by building galleries on the leaflets. Depending on the place of oviposition, a larva may penetrate leaf mesophyll, leaf petiole, and young shoots.
The mines expand as the larva develops, causing deformation or rot of the affected leaves. The larvae can migrate to another part of the plant, especially when they reach their maximum development or when the affected foliage withers and dries CIP ; Notz ; EPPO b.
Larval feeding causes desiccation of damaged leaves and shoots, resulting in low tuber production. Larval damage is generally accentuated in young plants in the tuberization phase. Possibilities of T. Pheromone traps can be used both for early detection and for monitoring the flight activity of the pest. They can also help to reduce the population when used for mass trapping, in which case a higher number of traps need to be deployed. Good agricultural practices for the control of T.
Nesidiocoris tenuis Reuter is an efficient predator of eggs and small larvae of the tomato tuber moth. Egg parasitoids of the family Trichogrammatidae are the natural enemies most used worldwide in biological control programs against Lepidoptera, through inoculative and inundative releases. Releases of Trichogramma pretiosum Riley reduced the population of T. Therefore, combinations with the application of a bioinsecticide based on Bacillus thuringiensis subsp.
Neem oil Azadirachtin acts as a contact and systemic insecticide and has been shown to be effective against low infestations of T. Several insecticides have been effectively used against T. Empoasca fabae Harris Hemiptera: Cicadellidae. Empoasca fabae adult a ; and potato leave damage b. Courtesy by CIP. Its main hosts are potato, alfalfa, eggplant, bean, celery, cucumber, cucurbits, groundnut Arachis hypogaea L. The potato leafhopper E. The attack on potato crops is sporadic and is favored by humid conditions.
Insects live in the abaxial lower part of the leaflets. They inject toxic saliva while feeding, causing leaf necrosis and interfering with plant growth.
Under severe attack, the attacked plants die prematurely. Leafhopper can transmit some viruses, although their occurrence is rare CIP ; Cook et al. The complex of symptoms caused by the leafhopper leads to reduced growth and reproduction of plants.
The relationship between yield loss and leafhopper numbers have been determined to be directly linear Radcliffe and Johnson Most of the potato leafhopper management in potato and other crops is based on monitoring, cultural control, and the use of insecticides. The presence of the leafhopper can be determined rapidly using entomological nets or yellow sticky traps located at the edges of the crop.
Nymphs are best monitored by examining the leaves, especially the underside. Monitoring middle part of a plant gives a more precise estimate of the population of leafhopper nymphs than monitoring basal and apical parts. Infestation of potato fields may be prevented by avoiding proximity to crops such as beans that host high leafhopper populations. Also, elimination of crop residues and appropriate irrigation help reduce populations of this pest Larrain et al.
Although the leafhopper has several natural enemies, such as predators and parasites, they play a very minor role in potato leafhopper control CIP ; Cook et al. Resistant or tolerant varieties should be considered in affected regions, but if leafhopper populations increase, systemic insecticides may become necessary Backus et al. Applications must be made only if populations reach economic thresholds.
Diabrotica viridula Fabricius, D. Adult of Diabrotica speciosa. South American Diabrotica species are presented in at least species in 24 families. Diabrotica speciosa larvae developed well on maize, peanut Arachis hypogaea L. Diabrotica viridula , preferred maize as adult and larval food, and for oviposition Cabrera Feeding on leaflets by adults interferes with photosynthesis and, therefore, reduces production of tubers.
Larvae damage stolons and form galleries in tubers Cabrera ; Lara et al. In some areas, the most important economic damage to potato is caused by the subterranean larvae gnawing the surface of tubers, which lose quality and become susceptible to soil pathogens CIP Eggs and larvae do not develop under dry conditions, so damage is most severe during wet seasons.
Deep tillage leads to exposing of larvae and pupae to the action of predators and adverse environmental factors. In cases of heavy infestation, especially when potato plants are small, insecticide applications are recommended against adult beetles CIP ; Sanchez and Vergara Since potato is a major crop for humankind, it has a global distribution and it is attacked by a myriad pests which can substantially reduce its productivity and its quality.
The increasing awareness about the nutritional, agronomic, and cash creating advantages potato provides is likely to further increase its status as a global crop, particularly in developing subtropical and tropical countries.
The development, adaptation and use of integrated pest management will be an important area of future research crucial for a sustainable and more resilient and economic profitable potato production in all potato growing regions worldwide. Emphasis should be given to develop and use biological approaches in pest management.
This will reduce the dependence on insecticides as well as will reduce the risk that insect populations develop resistance against insecticides.
Previous work has clearly shown that many insect pests of potato will respond to climate change by expanding their geographical range of distribution and increasing population densities will lead to greater crop and post-harvest losses, particularly in subtropical and tropical regions.
Modeling of the response of potato pest populations to global warming will help to predict potential changes in pest distribution and severity in order to support potato growers in the adaptation of their pest management strategies. Skip to main content Skip to sections. This service is more advanced with JavaScript available.
Advertisement Hide. Open Access. Keywords Solanum tuberosum Insect pest biology Insect pest distribution Pesticide resistance Climate change Integrated pest management. Download chapter PDF. Insecticide resistance is usually associated with several traits that may be taken advantage of when devising resistance management plans.
As a result, they are being outcompeted by susceptible insects. Also, in many cases resistance is inherited as an incompletely dominant or an incompletely recessive trait. Therefore, insects that are heterozygous at the resistant locus can be successfully controlled with sufficiently high dose of insecticide. So, resistance management techniques are generally directed towards preventing the situation when only highly resistant homozygotes survive in a population Alyokhin et al.
In practical terms, this can be achieved by doing the following: Monitoring insecticide efficacy. Individual potato IPM programs vary greatly depending on the specific agroecology and the socioeconomic conditions for which it is developed or adapted. However, they all share several important components, which distinguish them from the so-called conventional approaches that largely rely on calendar-based sprayings of pesticides.
Today it has a worldwide distribution and is considered the most damaging potato pest in the developing world Fig. Although this species is known as a pest of potato and tomato in South America and the Australian region, it does not attack any of these two crops in North America but instead feeds on black nightshade Solanum americanum Mill.
In , the pest was unintentionally introduced into Venezuela and then invaded Colombia and Ecuador. In , T. Since then the pest has been considered as a major threat to potato throughout southern Europe and was listed as a quarantine pest by the European and Mediterranean Plant Protection Organization EPPO a ; Kroschel et al.
In , it was finally recorded in mainland Spain where efforts are going on to eradicate the pest Jeger et al. Open image in new window.
Host range P. Symptoms of infestation P. Impacts on production losses P. Methods of prevention and control Control of the potato tuber moths must take place both in the field and in storage.
Storage management Potato tuber moth infestation occurs frequently in rustic farmer-managed potato stores in developing countries, especially if temperature is suitable for rapid population build up and the storage lasts for several months.
Distribution The pea leafminer Liriomyza huidobrensis is an agricultural pest endemic to South America Fig. Since the early s, the pest has been also recorded in many other countries around the world, presumably associated with the global trade of ornamental plants Mujica et al. Host range L. Symptoms of infestation Adults and larvae of L. Impacts on production losses L. Methods of prevention and control Ecological and economical sound control of the leafminer fly is best realized when based on IPM, which promotes natural enemies in combination with cultural practices and low-toxic insecticides Mujica ; Mujica et al.
The Andean potato weevil complex consists of at least 14 species with 12 in the genus Premnotrypes and two in the genus Rhigopsidius and Phyrdenus. The most important species attacking potato are Premnotrypes vorax , P. All Premnotrypes species show sexual dimorphism; the females 6. Distribution The Andean potato weevils Premnotrypes spp. Host range The host range of Andean potato weevils includes only potato and its wild relatives. Symptoms of infestation The Andean potato weevil, in the larval and adult stages, causes damage to the potato.
Following an accidental introduction, B. Host range B. Symptoms of infestation Both adults and nymphs feed by sucking the sap of plants.
Impacts on production losses Potato zebra chip disease is a serious disorder of potatoes that has resulted in millions of dollars in losses to the potato industry.
Methods of prevention and control Monitoring pest population. Distribution Prodiplosis longifila is a polyphagous species only in the Americas Fig. Its origin is unknown. Methods of prevention and control Crop management. Host range Colorado potato beetle is an oligophagous species feeding on about ten species of plants in the family Solanaceae Alyokhin et al. Symptoms of infestation Both adults and larvae are voracious leaf feeders and can completely defoliate potato plants.
Methods of prevention and control IPM programs against this potato pest emphasize reducing insect pest populations by using several control measures, including crop rotation, altered planting dates to avoid peak pest populations during vulnerable stages of crop development , and use of B. Distribution Ostrinia nubilalis is native to Europe and was introduced into North America near Boston Massachusetts in Baker et al.
Host range The European corn borer is primarily a pest of maize Zea mays L. Symptoms of infestation In potato, the most obvious sign of infestation is stem wilt. Impacts on production losses Potato plants present high tolerance for this insect; fairly high levels of infestation often do not seem to significantly affect tuber yields Kennedy Methods of prevention and control Sampling.
Distribution The green peach aphid, Myzus persicae , is thought to have its origins in China, just as its overwintering host plant, the peach Prunus persica L. Batsch Fig. However, the green peach aphid is highly adaptable and is currently cosmopolitan in distribution. The potato aphid M. Host range Both species are extremely polyphagous, being capable of feeding on several hundred-plant species Blackman and Eastop Symptoms of infestation Aphids can damage potato plants directly by feeding on sap, and indirectly by transmitting various viral diseases.
Impacts on production losses Direct damage : Large build-up in aphid population may result in death of heavily infested plants. Methods of prevention and control Biological control. Distribution Bemisia tabaci is a common pest in tropical and subtropical regions but is less prominent in temperate habitats Fig.
Trialeurodes vaporariorum originated in tropical or subtropical America probably Brazil or Mexico. Currently, it has become a cosmopolitan pest, with records in every zoogeographic region of the world CABI e , f. Symptoms of infestation Adult whiteflies can be easily seen on the underside of the leaves.
Methods of prevention and control Monitoring pest populations. Henosepilachna vigintioctomaculata Motschulsky , Henosepilachna vigintioctopunctata F. Distribution Henosepilachna vigintioctomaculata and H.
The ranges of both species overlap, particularly in China. However, H. Host range Potato ladybirds are polyphagous species feeding on a variety of plant species. Symptoms of infestation Both adults and larvae feed on potato leaves, causing their complete defoliation and eventual death in cases of severe infestation.
Impacts on production losses Potato ladybirds can be serious pests of potato. Distribution Cutworms are larvae of several noctuid moth species which are cosmopolitan Fig. Most widely distributed are the black cutworm Agrotis ipsilon , the variegated cutworm Peridroma saucia and the turnip moth Agrotis segetum. Their origin is uncertain but specimens which were used to describe A. Host range Cutworms are polyphagous and have been reported as a pest on nearly all vegetable crops and some cereals.
Symptoms of infestation The cutworm larvae remain in the soil at the base of the plant during the day. Methods of prevention and control Monitoring. Host range Army worms feed on a wide range of crops and are important pests especially in cereals.
Symptoms of infestation Armyworms are mainly forage feeders and feed during the day, do not make burrows, and may migrate in mass into potato fields from adjacent crops. Methods of prevention and control It is recommended to make suitable soil preparations that expose the pupa of the insect to environmental conditions and predators. Distribution Wire worms are the larvae of click beetles Fig. Over 39 species in 21 genera of wireworms have been reported to attack potato.
Wireworms are found throughout the world, and species vary greatly among regions. While in the UK, the three most important pest species in potato are Agriotes lineatus , A. Host range Grasses are the main host but they also attack potato, asparagus, carrot Daucus carota subsp.
Symptoms of infestation Wireworms are frequent pests in temperate climates, but less so in warm tropical areas. Impacts on production losses Wireworms may injure potatoes by feeding on the seed piece resulting in weak stands, but most of their damage is caused by tunneling into tubers, which reduces yield quality.
Distribution Epitrix spp. Epitrix tuberis Gentner and E. A nonnative pest of potato recently established and causing significant economic damage in Portugal and Spain was identified as Epitrix papa sp. Host range The host range comprises potato, tomato, eggplant, tobacco as well as weeds of the family Solanaceae. Symptoms of infestation Flea beetles are small beetles and jump easily in the foliage of plants. Impacts on production losses The flea beetles are considered one of the most serious pests threatening the entire EPPO region.
Methods of prevention and control Cultural control. Distribution Scarab beetles and thus white grubs are found worldwide. Host range White grubs are polyphagus and feed on over plant species including field crops such as potato, sweetpotato, maize, asparagus, and soybean; fruits such as apple, peach, grape, as well as trees and ornamentals Pathania and Chandel ; Visser and Stals ; Misra and Chandel Fig.
Symptoms of infestation White grubs are the larvae of relatively large beetles. Impacts on production losses Economic damage results mostly from larval damage to potato tubers.
Methods of prevention and control Cultural practices. Distribution The origin of the tomato or tobacco red-spider mite Tetranychus evansi is Brazil. The pest was accidentally introduced into Southern Africa during the s. The t w o spotted- or red-spider mite Tetranychus urticae and the broad mite Polyphagotarsonemus latus are widely distributed in both tropical and subtropical areas of the world CABI g , h Fig.
Host range Mites are polyphagous. Symptoms of infestation T. Impacts on production losses Plants with severe damage of P. Distribution The western flower thrips Frankliniella occidentalis originated in western North America and has since become a major pest on many crops across the US and around the world Fig. The onion thrip Thrips tabaci is thought to have originated in the Mediterranean region but is now found on all continents except Antarctica.
Host range F. Symptoms of infestation Thrips can cause major damage mainly during dry climatic conditions. Impacts on production losses Thrips are minor pest of potato. Distribution The tomato leaf miner, Tuta absoluta , was first identified in Peru by Meyrick in the year from samples collected in Huancayo m above sea level Fig. Since then, it has been recorded in all South American countries.
The pest is predominantly found in areas below m asl. It was first introduced into Europe in Spain in , from where it is believed to have spread to other European countries. Host range Hosts of T. Symptoms of infestation On potato, T. Impacts on production losses T. Methods of prevention and control Monitoring with pheromone traps. Distribution The leafhopper Empoasca fabae is widely distributed Fig. Host range E. Symptoms of infestation The potato leafhopper E.
Impacts on production losses The complex of symptoms caused by the leafhopper leads to reduced growth and reproduction of plants. Methods of prevention and control Most of the potato leafhopper management in potato and other crops is based on monitoring, cultural control, and the use of insecticides. Host range South American Diabrotica species are presented in at least species in 24 families.
Symptoms of infestation Feeding on leaflets by adults interferes with photosynthesis and, therefore, reduces production of tubers. Impacts on production losses In some areas, the most important economic damage to potato is caused by the subterranean larvae gnawing the surface of tubers, which lose quality and become susceptible to soil pathogens CIP International Potato Center, Lima, pp — Accessed 11 Jun Google Scholar.
Academic Press, Boston, pp — Google Scholar. Alyokhin A Colorado potato beetle management on potatoes: current challenges and future prospects. The latest outbreak in England was two months ago in the south-west, from Dutch seed, which was contained.
Symptoms include wilting of the potato plant, but the disease is most noticeable in tubers. A brown ring is found if the tuber is cut in half and in severe infections, the vascular regions rot away completely. Colorado beetle was first recorded as a pest in the USA in It is widely established in much of continental Europe, having first arrived in Bordeaux in , but not the UK.
With climate change, the risk of it extending its range and becoming established in Britain is increasing. It is one of the best known beetles and is famous for devouring potatoes, tomatoes, egg plants and peppers. Adult beetles as well as their larvae can strip plants of leaves and ruin an entire crop. Dome-shaped adults are nearly 0. The beetle has developed a resistance to all major insecticide classes used in the UK.
Small black beetles that originated in North America, flea beetles have spread rapidly through Portugal since The larvae cause corky lesions and superficial warty growths on potato tubers and the adults, small black beetles, cut holes in leaves. The main impact is the loss of commercial value of the tubers — damaged tubers are rejected. Yield does not appear to be affected. The adults are active fliers and it is possible that juvenile stages or adults may be spread with tubers or soil.
Potato tubers or soil attached to the tubers could carry the pest as larvae, pupae or overwintering adults over long distances. In potatoes, symptoms in the field may be difficult to recognise before plants mature.
Potato plants infected with a severe infection of PSTVd are upright, stunted and much thinner than normal plants. Leaves are smaller, may be grey and twisted or distorted. Potatoes left in the ground will eventually rot causing pest and disease. Easy to identify by the black blotches which appear on the leaves first. These then appear on the stems and the plants quickly begin to collapse. Leaf which has potato blight For more information on Potato Blight check out our comprehensive article on how to identify and treat potato blight.
It is not restricted to potatoes it affects other vegetables which form under the soil such as beetroot and radishes. The slugs burrow into the tubers when they are growing and leave tunnels in them with the surrounding flesh being turned brown. Affected potatoes are almost totally inedible. See the picture below. Slug Damage Normally with slugs they can be killed by the use of slug pellets but the slugs which damage potato tubers remain almost exclusively below ground so slug pellets on the surface have little effect.
If the problem is widespread grow early varieties which are not in the ground long enough for slugs to be a problem. Do not manure the ground before planting which encourages slugs, use blood, fish and bone as a fertiliser instead. Lift potatoes as soon as possible, slug damage normally starts at the beginning of August. Look at the potato plants stem and if it is black or brown at soil level spreading upwards as the disease progresses then you know your plants have Potato Blackleg.
It has two different Latin name as well just to complicate matters. The official names are Globodera rostochiensis golden nematode and Globodera pallida white nematode , but they are sometimes referred to by their old Latin names Heterodera rostochiensis and Heterodera pallida.
Colour aside, they are one and the same potato eelworm.
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