Weevil larva feeding inside a pepper..fruit..unopened flower

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1 Commodity-Based Pest Insect Info Pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) Pengxiang Wu 1,2, Muhammad Haseeb 1, Chinemenma Okoroji 1, Lambert Kanga 1 and Jesusa Legaspi 3 Pepper weevil (PW), Anthonomous eugenii Cano (Coleoptera: Curculionidae), is an economically important invasive insect pest of cultivated peppers in the southeastern United States. The pest is native to Mexico, and widely distributed in the southern United States, Mexico, Central American, and the Caribbean. Adult pepper weevils feed on fruit and leaf buds and lay eggs on flowers, buds and fruits. Larvae feed inside the fruit, causing premature fruit drop and often significant crop losses of 50% or more. Larger fruits do not immediately drop. Entire infested fields are often abandoned because of concern in shipping infested fruit to markets. Under heavy infestation, the entire pepper crop must be removed from the field because the infestation poses a serious threat to future pepper crops. Because young plants for transplanting are shipped northward each spring, the PW sometimes occurs in the northern States. In central and south Florida, adults are commonly found from March until June reflecting the availability of peppers, but a few can be found throughout the year except in December and January. In north Florida, the species can be found most of the year except mid-december to late-february. Under suitable weather conditions, the PW requires 20 to 30 days to complete its life cycle. Under insectary conditions in California, up to eight generations have been produced in a single year, but three to five generations is probably normal in most locations. The adults are long-lived and produce overlapping generations, so it is difficult to determine generation number accurately. The shipment of infested fruits and plants have regulatory and trade implications. Because of its minute size and cryptic nature, the weevil can also escape primary inspections at the port of entries. Weevil feeding on an unopened flower. Weevil larva feeding inside a pepper..fruit..unopened flower Adult weevil exist holes in jalapeno peppers. Identification. Adult beetles are oval in shape, mm long, mm wide, mahogany-brown to black, with a strongly-arched body and a long, stout beak. The thorax and elytra are mostly covered with small scales. Antennae are long and markedly expanded at the tip. Each femur bears a sharp tooth. Pupae resemble adults in form, except that wings are not fully developed and large setae are found on the prothorax and abdomen. Pupae are white when first formed, but eventually become yellowish with brown eyes. Larvae are white to gray in color, with a yellowish brown head. Larvae lack thoracic legs and have few large hairs or bristles. Eggs are white when first deposited, but soon turn yellow. They are oval in shape and measure 0.53 mm in length and 0.39 mm in width. Host Plants. Pepper weevils attack all species of pepper (Capsicum spp.) as well as nightshades (Solanum spp.). The American black nightshade, S. americanum, is an important alternative host plant. Distribution. The origin of the pepper weevil likely is Mexico, but it is found throughout most of Central America, the Caribbean, and the southern United States. It was found in Texas in 1904, California in 1923 and Florida in 1935, and is now found across the southernmost United States from Florida to California. However because transplants are shipped northward each spring, pepper weevil sometimes occurs in more northern locations. The PW was first observed in Hawaii in 1933 and in Puerto Rico in Damage. Destruction of blossom buds and immature fruits is an important form of pepper damage. Both adult and larval feeding causes bud drop. Adult feeding punctures appear as dark specks on the fruit, and are not very damaging. Sometimes the fruit is deformed. Fruit drop is very common and is the most obvious sign of infestation. Larval feeding within the mature pod is another important form of damage, causing the core to become brown, and often moldy. The stem of pods infested by larvae turn yellow, and the pod turns yellow or red prematurely. Punctures caused by pepper weevil allow penetration of the fungus Alternaria alternata. 1 Center for Biological Control (CBC), College of Agriculture and Food Sciences, Florida A&M University (FAMU), Tallahassee, Florida, The United States. 2 Institute of Zoology, Chinese Academy of Sciences, Beijing, China, and 3 CBC, USDA, ARS, Tallahassee, Florida, The United States. Page 1

2 Commodity-Based Pest Insect Info Monitoring and Pest Density Inspect two terminal vegetative buds per plant in the morning at least twice weekly. Sampling should be concentrated on field perimeters. Use yellow sticky traps and pheromone traps for adults. Use boll weevil traps baited with pepper weevil pheromones. Make direct adult weevil counts using whole plant inspections. Scout for feeding damage or egg laying in terminal bud clusters. Biology and Ecology A female oviposits 5 to 7 eggs per day with a mean fecundity of 341 eggs per lifetime. Egg stage (4.3 days) is followed by the first (1.7 days), second (2.2 days), and third (8.4 days) instars, then pupa (4.7 days), and adult; hence, the duration from egg to adult emergence is 21.3 days. Pupation occurs within a flower or fruit and, upon emergence from the pupa, the adult escapes from the fruit by making a round exit hole. Maximum A. eugenii fecundity (3.1 eggs per female per day), shortest development time (12.9 days), and minimal mortality were obtained at 30 C, the temperature for maximum population increase. One generation is completed in 20 to 30 days, and up to 8 or more generations can be completed depending upon the weather conditions and host plant availability. Pest Management Strategies Two important parasitoids of PW are Catolaccus hunteri Crawford (Hymenoptera: Pteromalidae) and Bracon mellitor Say (Hymenoptera: Braconidae). Avoid locations with pepper weevil infestations when selecting sites for a new pepper crop. Scout fields weekly beginning at transplanting or before first bloom. Also scout nightshade plants and old pepper residue in the area to determine if a preplant cleanup is needed. Avoid carry-over of weevils from one season to the next. This is a problem where peppers are cut back to produce a second crop or crop residue is left standing after harvest. If weevils infest early in the season, begin controls at first bloom to prevent an early build-up of pepper weevil. Action threshold: 1 adult per 400 terminal buds or 1 adult per trap. Target insecticide sprays at the adults by getting good spray coverage and timing applications with the presence of adults or their emergence from fallen fruit. References Addesso K.M., and H.J. McAuslane Pepper weevil attraction to volatiles from host and non-host plants. Environmental Entomology, 38(1): Anderson R.S., O Brien CW, Salsbury GA, Krauth SJ, Orchestes alni (L.) Newly discovered in north america (Coleoptera: Curculionidae). Journal of the Kansas Entomological Society, 80 (1): Cortez E.M., E.D. Cabanillas, and B.D. Armenta Parasitoids and natural parasitism of the pepper weevil Anthonomus eugenii in the north of Sinaloa, Mexico. Southwestern Entomologist, 30(3): Eller F.J., and D.E. Palmquist Factors affecting pheromone production by the pepper weevil, Anthonomus eugenii Cano (Coleoptera: Curculionidae) and collection efficiency. Insects, 5(4): Schuster, D.J Suppression of Anthonomus eugenii (Coleoptera: Curculionidae) pepper fruit infestation with releases of Catolaccus hunteri (Hymenoptera: Pteromalidae). Biocontrol Science and Technology, 17(4): Toapanta M.A., D.J. Schuster, and P.S. Stansly Development and life history of Anthonomus eugenii (Coleoptera: Curculionidae) at constant temperatures. Environmental Entomology, 34(5): For further information, please contact Center for Biological Control, Florida A&M University. Phone: Page 2

3 Commodity-Based Insect Pest Info Citrus Root Weevil, Diaprepes abbreviatus (Coleoptera: Curculionidae) Jing Zhang 1, 2, Muhammad Haseeb 1, Runzhi Zhang 2 and Lambert Kanga 1 Citrus Root Weevil (CRW), Diaprepes abbreviatus (Coleoptera: Curculionidae) is serious invasive insect pest of citrus in Florida. The pest is native to Caribbean basin. In Florida, it was introduced in 1964 via an ornamental plant shipment from Puerto Rico. Since then, the pest has spread over a large areas of central and southern Florida. Recently, it has been recorded in north Florida in Leon County, where it is feeding and breeding on citrus and other host plants. Earlier economical estimate showed that the pest causes about $70 million in damage annually in Florida alone and infesting more than 100,000 acres of citrus. The seasonal annual abundance of adult weevils in citrus groves can be monitored using tedders traps to capture young adults. The CRW adult emergence from the soil and first peak of the population density can be seen in late May to early July and the second peak in late August to October. No pheromones are available to monitor pest density. Monitoring and sampling of larvae is difficult because larvae feed on roots below ground. The damaged roots provides opportunity to Phythophora fungus. A single larva can kill a young citrus plant while several larvae can cause serious damage to mature plants. Adult presence and feeding on citrus leaves usually alerts growers to control this serious pest. Brigade WSB, a synthetic pyrethroid is the only pesticide registered for young larval control. Certain nematode species naturally occurring in Florida s soil can provide some control, however, due to heavy application of pesticide to control citrus psyllids during last 10 years has diminished their densities to provide effective control. Very few natural enemies of the citrus root weevil were found including two egg parasitoid, Tetrastichus haitiensis and Ceratogramma etiennei and certain general predators including a predatory stink bug, Euthyrhynchus floridanus, the regal jumping spider, Phidippus regius, and several species of ants. Their potential to manage this serious pest under field conditions need to be determined. Citrus leaves damage by the Citrus Root Weevils Adult Citrus Root Weevil Identification. Adult: 0.95 to 1.90 cm long, dark black body covered by minute white, orange, and/or yellow circular scales on the elytra. The scales on the elytra are often rubbed off on the ridges in older weevils giving the appearance of dark brown to black stripes. Egg: 1.2 mm long and about 0.4 mm wide, oblong-oval in shape and are laid in clusters of 30 to 265 and enclosed within leaves that have been folded and glued together by the female. Larva: White and legless reaching a mature length of about 2.5 cm. The head capsule has variable light and dark areas. Host Plants. Common host plants include citrus, papayas, sweet potato, sugarcane, cotton, peanut, corn, and other plant species. The pest is known to feed on over 270 species of plants within 59 different families. Distribution. The species is native to Caribbean basin particularly, Jamaica, Dominican Republic, and the lower Antilles. In the United States, the pest is currently found in Florida, Louisiana, Texas, California, and Puerto Rico. Damage. Both larval and adult stages of pest can cause serious damage to host plants. In citrus, larvae feed on roots. After infestation, the plant roots become more vulnerable to Phytophthora fungus. A single larva can kill a young citrus plant. In mature plants, few to several larval feeding can cause serious damage. Adult notches the leaves and tender shoots, however most plants can tolerate this damage except the young ones. 1 Center for Biological Control (CBC), College of Agriculture and Food Sciences, Florida A&M University (FAMU), Tallahassee, Florida, The United States. 2 Institute of Zoology, Chinese Academy of Sciences, Beijing, China. Page 1

4 Commodity-Based Insect Pest Info Monitoring and Pest Density. The CRW adults can be monitored using tedders traps in the citrus groves. To detect adult infestation, one can easily monitor damaged leaves due to CRW feeding by visual observations. Visual observation of scars on fruits are also normally helpful to know infestation levels. To collect adult weevils, hold a white paper plate right under a branch and shake or beat the branch to dislodge the plum curculios. The use of regular insect sweep nets for collection are useful. Because of good size, adult weevils can be also hand-picked from host plants. Because larvae feed on roots under the ground, their monitoring is difficult. Earlier studies suggest that adult emergence often overlaps with the onset of summer rains in late-may through June in central Florida and July to August in north Florida. Biology and Ecology. A single female can lay cluster of 30 to 260 eggs between two leaves or inside the folded edge of a citrus leaf. Upon emergence, the young larvae drop from leaves to the soil surface and burrow into the soil and start feeding on small fibrous roots. The older larvae burrow into larger roots. Larvae are unable to burrow into dry soil. The last two larval instars (10 & 11) does not feed much and enter a quiescent/ pre-pupal period. After feeding for several months, the mature larvae pupate in the soil. The pupae remain in a pupal chamber in the soil for 15 to 30 days. Adult weevils will not emerge from soil if the soil is dry and compacted. Therefore, irrigation or rainfall promotes adult emergence. The life cycle can be completed in 5 to 18 months depending upon the temperature and soil moisture. Adult weevils are strong flyer. They feed during the early morning and late afternoon. The CRW adult emergence from the soil and first peak of the population density can be seen in late May to early July and the second peak in late August to October. Pest Management Strategies. Application of Brigade WSB, a synthetic pyrethroid as soil barrier can be applied to neonatal larvae to manage CRW. Current increase in use of insecticides to manage Asian citrus psyllid has caused negative impact on the potential use of nematodes to control larvae of CRW. Conservation of natural occurring parasitoids, and predators, including nematodes by applying safer pesticides can be useful to manage CRW. Phytophthora-resistant/tolerant citrus rootstock can provide protection against the disease. Adult weevils will not emerge from soil that is dry and compacted. Therefore, frequent irrigation practice may increase adult emergence. References Bender, G. S., L.M. Bates, J.J. Bethke, E. Lewis, G. Tanizaki, J.G. Morse, and K.G. Godfrey Evaluation of insecticides, entomopathogenic nematodes, and physical soil barriers for control of Diaprepes abbreviatus (Coleoptera: Curculionidae) in citrus. Journal of Economic Entomology, 107(6): doi: /ec Duncan, L.E., M.E. Rogers, S.H. Futch, and J.H. Graham Florida citrus pest management guide: Ch. 13 citrus root weevils. UF-IFAS Extension. Document No: ENY-611 (rev.). 4 pp. Sandoval-Mojica, A. F. and J.L.Capinera, J. L Antifeedant effect of commercial chemicals and plant extracts against Schistocera americana (Orthoptera: Acrididae) and Diaprepes abbreviatus (Coleoptera: Curculionidae). Pest Management Science, 67(7): doi: /ps Weissling, T.J., J.E. Pena, R.M. Giblin-Davis, and J.L. Knapp, Jr Diaprepes root weevil, Diaprepes abbreviates (Linnaues) (Insecta: Coleoptera: Curculionidae). UF-IFAS Extension. Document No: EENY-024 (rev.). 5 pp. For further information, please contact Center for Biological Control, Florida A&M University. Phone: Page 2

5 Source: Source: Commodity-Based Insect Pest Info. Plum Curculio, Conotrachelus nenuphar (Coleoptera: Curculionidae) Plum curculio, Contrachelus nenuphar (Coleoptera: Curculionidae) is a common pest of numerous fruit crops in north Florida including plum, peaches and other stone fruits. The pest also feed on the pome fruits and blueberries. This is a native pest species, frequently found in the east of the Rocky Mountains in the United States and Canada. In some orchards, damage from plum curculio leads to a large percentage of fruits that are unmarketable and inedible. Effective non-chemical controls for plum curculio have not yet been developed. If this insect is more than a nuisance in your planting you can try sanitation and shaking or beating the branches but these methods probably won t be sufficient, and you will probably need to apply certain chemical control measures to manage it successfully. Plum Curculio Adult Plum Fruits Showing Oviposition Scars Identification Adult plum curculio is a small brownish-black snout weevil. Adult is 4-6 mm long, mottled with lighter gray or brown markings. Their backs are roughened and bear two prominent humps and two smaller humps. Larvae are slightly curved, yellowish-white, legless, brown-headed grubs. Larva is 6-9 mm long when fully grown. Host Plants The favorite hosts included wild plum, crab apple, cherry, and similar plants. Major fruit-attacking insect pest of peaches and other stone fruits. Plum curculio is also a pest of pome fruit and blueberries. Distribution This is a native pest species, frequently found in the east of the Rocky Mountains in the United States and Canada. Damage Both adult and larval stages of the plum curculio damage fruits. In nectarines and plums, adult damage consists of tiny circular feeding punctures or small crescent-shaped oviposition wounds made by females immediately adjacent to egg-laying punctures. In peaches, it is more common to see a 4 mm area of shiny fuzz. Teasing away the fuzz will expose a feeding or oviposition scar, possibly an oval white egg or brown larval tunnel into the flesh. These feeding and oviposition sites cause conspicuous scarring and malformation as the fruit enlarges, plum curculio feeding looks like the injuries caused by cat-facing insects or cold. The larvae tunnel and feed in developing fruit, usually boring to the pit. Most peaches infested by plum curculio early in the season drop prematurely. Larger peaches, infested after pit hardening begins, generally stay on the tree until ripe, but these wormy fruit are of no value due to the flesh damage and/or presence of the grubs. Monitoring and Pest Density The pest levels can be monitored using pyramidal traps. To detect plum curculio s infestation on fruits a 10X hand lens is useful for clear observations. Page 1

6 Commodity-Based Insect Pest Info. Visual observation seeing scars on fruits are also normally used to know infestation levels. Hold a white paper plate right under a branch and shake or beat the branch to dislodge the plum curculios. Start looking for the adults before the flowers have opened and check every few days. In the morning, when the insects are cold, they will fall onto the plate rather than flying away. Even cutting of some fruits with a knife and observing them with a hand lens can be practicable. Biology and Ecology The plum curculio exhibits four life stages: egg, larva, pupa and adult. Eggs are deposited under the skin of the fruit in a small, crescent-shaped cavity. After approximately one week, the eggs hatch into tiny, legless whitish larvae. Larvae have distinctive brown head capsules with well-developed mandibles. There are four larval instars. Pupal stage is spent underground, usually in the upper two inches of soil. Pupa is whitish or cream-colored, and is characterized by having the appendages free from the body and looking like a mummified adult. Adult is a small, rough snout weevil. A complete life cycle, from egg to adult, takes about 50 to 55 days. Temperature and moisture conditions play a major role in regulating plum curculio development and activity. Weevils are more active on warm, damp, cloudy days and in thick, heavy stands of trees that provide abundant moisture in the center of the orchard. Plum curculio activity nearly ceases when temperatures drop below 60 F; however, if temperatures reach 70 to 75 F for two days before petal fall, the weevils may begin to feed and mate. In the spring, plum curculio adults leave their overwintering places and migrate to fruit trees just about bloom time. Pest Management Strategies Adult populations are suppressed in the spring by well-timed applications of effective insecticides. Keeping the orchard floor closely mowed after harvest affords less protective cover to adults that overwinter in the orchard. Destruction of nearby plum thickets, abandoned peach blocks, and other alternate hosts is suggested to reduce plum curculio migration into orchards from outside sources. Sprays provide a protective barrier to prevent overwintering adults from laying first generation eggs. Sprays for plum curculio control are normally initiated at shuck split. Two or possibly three additional sprays at 10- to 14-day intervals are needed to assure control of the overwintered population. In infested orchards, special attention should be given to mid- and late-season cultivars by applying recommended insecticide sprays at six, four, and two weeks before harvest. References Bloem, S., III., R. F. Mizell, and C.W. O Brien. Old traps for new weevils new records for curculionids (Coleoptera: Curculionidae), Brentids (Coleoptera: Brentidae), and Anthribids (Coleoptera: Anthribidae) from Jefferson Co. Florida. Fla. Entomol : Byrne, D. N. and T. S. Bellows, Jr Whitefly biology. Ann. Rev. Entomol. 36: David J., T. Cottrell d, D. Horton, A. Hodges, and G. Hodges. Hosts of Plum Curculio, Conotrachelus nenuphar (Coleoptera: Curculionidae), in Central Georgia. Environmental Entomology 35(1): Johnson, D., Mizell, R.F. III, and D. Horton. Plum curculio. Available online (accessed on 25 January, ). 3 pp. Johnson, D. T Jr, P. G. Mulder, B. D. McCraw, B. A. Lewis, B. Jervis, B. Carroll, and P. J. McCleod. Trapping plum curculio Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae) in the southern United States. Environ. Entomol : For further information, please contact Center for Biological Control, Florida A&M University. Phone: Page 2

7 Source: UC, IPM Source: WSU Center Commodity-Based Insect Pest Info. Spotted Wing Drosophila, Drosophila suzukii (Diptera: Drosophilidae) The Spotted Wing Drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae) is a new invasive species that is native to South East Asia. It was first detected in North America in The SWD is spreading rapidly and economic losses are severe to soft-skin fruit crops. Fruits industry and growers are concerned about the continuous rise in population density, and the rising damage rates of this pest. The SWD causes larval infestations in stone and berry fruits. The SWD are able to deposit eggs in healthy unwounded fruit using the serrated female ovipositor. Egg laying introduces fungal pathogens which causes fruit rot. There are several management practices and monitoring tools to reduce the risk of SWD. SWD Female and Male SWD Adult depositing eggs in blackberry fruit Identification Adult body length is approximately 2-3 mm, red eyes, yellowish- brown body color and dark bands across the abdomen. Males have a small dark spot on each wing tip. Females lack the wing spot. Females possess a serrated ovipositor which enables it to penetrate thin skinned fruits and deposit eggs into fruit. Egg measures 0.6 mm long, oval, white, and possess 2 filaments at one end. Larva is legless, headless, up to 6 mm long at maturity, white or transparent in color. Pupa is around 3 mm long, brown, football-shaped, two stalks with small finger-like projections on one end. Host Plants The SWD is able to lay eggs in healthy unwounded fruits. Crops that are potentially at risk include soft-skinned fruits at the ripening stage such as blueberries, blackberries, raspberries and strawberries. Distribution More than 70% of the U.S small fruit production occurs in the Pacific to Atlantic coastal areas. Continuous infestation to new areas is likely due to being packed and shipped with fruit from region to region. This can be avoided by carefully monitoring fruits for its presence. Damage Single outer spots on the fruit that are wrinkled will suggest where the female SWD has pierced the fruit using her serrated ovipositor. By opening the fruit, fruit growers can visually see the larvae inside. The larvae destroy the infested fruits in a matter of a few days. Monitoring and Pest Density Monitor fruits regularly especially when fruits start ripening. Fruit growers should look for signs of fruit rotting or decaying. Use of traps is recommended in the field to know the arrival of flies. Page 1

8 Commodity-Based Insect Pest Info. Biology and Ecology A single female can lay one to 60 eggs per day and eggs in her lifetime. A female lays approximately one to three eggs per oviposition site. The eggs are laid singly and are randomly distributed on fruits. Multiple clutches of larvae may be present on the same fruit because females may oviposit on the same fruit. A single life cycle of the SWD last days. Eggs develop and hatch within the fruit in which they are laid. Pupation occurs inside and outside of the fruit. Up to 13 generations can be completed in one year depending on the prevailing ecological conditions. The SWD prefer a moderate temperature. Adult activity occurs between 68º F to 86º F. Pest Management Strategies Fly trapping or visual inspection will determine if a field has been infested with the SWD, and serves as a mean to monitor levels of infestation. Sanitation- To avoid infestation levels on later ripening fruit, or infestation on future crops sanitation should be practiced. This includes eliminating any fruit that has fallen on the ground and any infested fruit remaining on plants. Biological Control- Natural enemies of the SWD would require further investigation. Netting- Nets should be applied before the fruit begins to ripen, to avoid trapping the pest inside. Nets should be tightly secured over the entire host to avoid infestation. Insecticide- There has been limited research on treatments. Sprays must be timed to kill adults before the SWD lay eggs, as sprays will not control larvae already in the fruit. Many insecticides are very toxic and not recommended due to drift and runoff. References Cha, D. H., Adams, T., Werle., C.T., Sampson, B.J., Adamczyk, J.J A four component synthetic attractant for Drosophila suzukii. Dhami M.K. and L. Kumarasinghe A HRM Real-Time PCR Assay for Rapid and Specific Identification of the Emerging Pest Spotted-Wing Drosophila (Drosophila suzukii). PLoS ONE 9(6): e Doi:1371/journal.pone Joanna C. Chiu, Xuanting Jiang, Li Zhao, Christopher A. Hamm, Julie M. Cridland, Perot Saelao, Kelly A. Hamby, Ernest K. Lee, Rosanna S. Kwok, Guojie Zhang, Frank G. Zalom, Vaughn M. Walton, David J. Begun. Genome of Drosophila suzukii, the Spotted Wing Drosophila. Oregon State University. Kanzawa T Studies on Drosophila suzukii Mats. Kofu. Review of Applied Entomology 29: 622. Radcliffe B, Edward., D. Hutchinson, William., E. Cancelado, Rafael. Integrated Pest Management Cambridge Michigan State University For further information, please contact Center for Biological Control, Florida A&M University. Phone: Page 2

9 Source: Bugguide.net Source: CBC, FAMU Commodity-Based Insect Pest Info. Yellowmargined Leaf Beetle, Microtheca ochroloma (Coleoptera: Chrysomelidae) The yellowmargined leaf beetle (YMLB), Microtheca ohcroloma, is an introduced pest of cruciferous crops in the southern United States including Florida, and arguably the most damaging pest of organic crucifer vegetable production in the region. The YMLB was first reported in Alabama in Today this leaf beetle is active along the gulf coast from Florida to Texas, and in Georgia and North Carolina. For the conventional grower, the YMLB is a major concern. Plantmediated pest management against this serious pest can be a useful option to control it successfully. Identification YMLB Adult Turnip Damage by YMLB The adult is about 5 mm long; usually the females are larger than the males. The yellow-margined leaf beetles elytra are brownish to black with yellow margins. The egg is bright orange, elongate, and laid singly or in small groups on plant stems, under fallen leaves or on the soil surface The larva is grayish to yellow-brown, covered with a fine layer of hairs and has a dark, sclerotized head capsule that is brown or black. Pupal cases are attached to the undersides of leaves, and their dark color stands out against the green foliage. Host Plants Plants belonging to the crucifer family are the normal host for this species. broccoli cabbage cauliflower collards mustard radish turnip watercress Turnip is the most preferred host for this flea beetle, followed by mustard, radish, collards and cabbage. The beetle is also a pest of mizuna, mibuna, napa cabbages which are high-value crops which are often grown organically. Distribution The YMLB is an invasive insect pest, found in several South American countries (Argentina, Brazil, Chile, and Uruguay) where it is native. Since then, it has spread throughout most of the southern states: Alabama, Mississippi, Louisiana, Texas, North Carolina, Georgia, and Florida. In Florida, the YMLB is present in the field during the coolest months, which corresponds with the primary production season for leafy greens. Page 1

10 Commodity-Based Insect Pest Info. Damage Most damage occurs in the spring when both the larvae and adults are found feeding on crucifers. They feed on the foliage and leaf margins, making small holes. Adults and larvae often defoliate the host. Larvae, especially early instars, work in groups to strip individual stems. The beetle's host plants thrive in the cool months from October to April, and this period comprises the growing season for organic farmers in Florida. Monitoring and Pest Density Monitor field plants for egg masses, larvae, pupae and adults. One adult or larva per plant is the threshold to apply control measures. Biology and Ecology The eggs are bright orange and are laid on the soil or dry leaves. The larva is yellow to brown with a sclerotized head capsule. When the larva is ready to pupate, it builds a brownish, net-like pupal case to surround itself. The YMLB takes 27 days to develop from egg to adult at 20 C and the adult can live up to 6 months. Both larvae and adults feed on the plant foliage and can completely defoliate their host plants. Larvae are gregarious during their early instars, but become solitary later. Adults can start copulating six days after they emerge from pupae, and females can lay eggs three to six days later. Pest Management Strategies The YMLB is not a problem for the average grower, as it usually is controlled by foliar insecticides used against other insect pests. However, it is a problem for organic growers who cannot use these materials or homeowners who choose not to use insecticides. Field sanitation should be practiced also. Perimeter trap cropping and release of Spined solder bug has the potential to lower pest population. References Ameen A.O, Story R.N Feeding preferences of larval and adult Microtheca ochroloma, (Coleoptera: Chrysomelidae) for crucifer foliage. Journal of Agricultural Entomology 14: Thomas R.F Common name: Yellowmargined leaf beetle scientific name: Microtheca ochroloma Stål (Insecta: Coleoptera: Chrysomelidae) Featured Creatures UF/IFAS, Entomology and Nematology Department. EENY-348 Wilkerson JL, Webb S.E, Capinera JL Vegetable Pests I: Coleoptera - Diptera - Hymenoptera. UF/IFAS CD-ROM. SW 180. For further information, please contact Center for Biological Control, Florida A&M University. Phone: Page 2