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Publication #ENY-461

Insect Management for Tomatoes, Peppers, and Eggplant1

S. E. Webb, P. A. Stansly, D. J. Schuster, J. E. Funderburk, and H. Smith2

Pest management should be based on the proper identification of pests and knowledge of their biology. The major pests of tomatoes, peppers, and eggplant in Florida and guidelines for their management are described below. Some insects may be more important in some areas of the state than others. Scouting guidelines and action thresholds for tomatoes are from the Florida Tomato Scouting Guide, SP 22, 2nd edition.

For each pest described, a table of management options will be found after the damage. These tables will be expanded as more information becomes available. Tables 12–14, at the end of this publication, list pesticides labeled for each major fruiting vegetable grown in Florida: tomatoes, peppers, and eggplants. Pesticides for controlling insects not described below can be found by looking under the "Insects" column in the tables.

Silverleaf Whitefly, Bemisia argentifolii

Description

The adult silverleaf whitefly (Figure 1) [6 March 2013] is small, approximately 1/16 of an inch in length, and has powdery white wings held tent-like over a yellow body while at rest. Whiteflies are usually found on the undersides of leaves, often in pairs. Males are smaller than females. Eggs, which are yellow and football-shaped, are attached upright by a tiny stalk inserted into the lower leaf surface. A mobile first instar or crawler stage hatches from the egg and settles on the leaf. It then develops through immobile second, third, and fourth instars, which look like semi-transparent, flat, oval scales. The fourth instar or "pupa" is more yellow and more easily seen without the aid of a hand lens, typically has very distinct eyespots, and is referred to as a "red-eyed nymph."

Figure 1. 

Silverleaf whitefly.


[Click thumbnail to enlarge.]

Biology

The life cycle from egg to adult can be as short as two weeks when the weather is very warm. Adult females lay most of their eggs on young leaves so young nymphs also generally occur on the underside of younger leaves. As the plant grows, leaves bearing the maturing nymphs are found lower down on the plant, so older nymphs can be found by looking at older leaves. Whiteflies ingest sap from the plant vascular system (phloem) through stylets similar to those of aphids and, like aphids, process a relatively large volume of plant sap by excreting excess liquid in the form of a sugary substance called honeydew.

Damage

Heavy whitefly populations can damage plants directly by removing sap. The honeydew that they excrete while feeding serves as food for sooty mold, which can reduce the amount of light reaching leaves. Moderate numbers of nymphs can cause irregular ripening of tomatoes, characterized by incomplete ripening of longitudinal sections of fruit. Nymphal feeding also causes an increase in objectionable white tissue in interior fruit walls. Adults also transmit plant viruses. After feeding on infected plants, whiteflies can then transfer the virus to healthy plants. Unlike the mosaic viruses transmitted rapidly by aphids, the whitefly-transmitted geminiviruses commonly found in tomatoes are transmitted persistently. It takes longer for the whitefly to acquire the virus and the virus must pass through the body of the insect into the salivary glands before the whitefly can transmit it to a healthy plant. The whitefly has to feed on a healthy plant for some time to cause infection. Once the whitefly acquires the virus, it may transmit it for the rest of its life. In addition to Tomato mottle virus, the very severe Tomato yellow leaf curl virus is now common in Florida.

Silverleaf whitefly can reach high numbers on tomato and eggplant and can be a problem on peppers. Generally, whitefly populations are highest in South, Southwest and West Central Florida during the spring although, in West Central Florida, the number of whiteflies carrying virus is usually higher in the fall. The whitefly is less often a problem in North Florida but may reach damaging numbers in summer and fall. Tomato yellow leaf curl virus causes problems in all tomato-growing areas in Florida.

Aphids

Description and Biology

Aphids (Figure 2) are soft-bodied, sucking insects that can rapidly colonize plants due to their short generation time. Adults are delicate, pear- or spindle-shaped insects with a posterior pair of tubes (cornicles), which project upward and backward from the dorsal surface of the abdomen and which are used for excreting a defensive fluid. In Florida, winged and wingless forms are all female and give birth to living young (nymphs). Nymphs are smaller but otherwise similar in appearance to wingless adults, which they become in 7 to 10 days.

Figure 2. 

Winged aphid (top) and wingless aphid (bottom).


[Click thumbnail to enlarge.]

The green peach aphid, Myzus persicae, is the most common aphid species in Florida peppers and tomatoes, although the potato aphid (Macrosiphum euphorbiae) may also occur. Green peach aphid adults vary from 0.04 to 0.08 inch in length and are light green to yellow to pink and pear-shaped. The tubercles (bumps between antennae) point inward and are a distinguishing characteristic. Winged forms have a black patch on the back of the abdomen.

Damage

Heavy aphid infestations may cause stunting and leaf distortion. Feeding on blossoms reduces fruit set. Sooty mold will grow on the honeydew that the aphids excrete. They also spread plant viruses such as Tobacco etch virus, Potato virus Y, and Pepper mottle virus. Most transmission results from winged aphids probing the leaf surface, rejecting the plant as a host, flying to another plant, and probing again. Aphids that settle, feed, and reproduce on the plant are less likely to transmit virus. Aphids can acquire and transmit the virus in a matter of seconds (although they lose the virus after probing a few plants) so conventional insecticides are of no help in controlling the spread of these viruses. Sources of infection are nearby virus-infected tomato, pepper, tobacco or other host plants. Related weeds such as nightshade may also be infected and serve as a source of virus for the crop.

True Bugs (Hemiptera)

Description

Like aphids and whiteflies, true bugs are sucking insects. True bugs can be recognized by their front wings, which are leathery close to the body but membrane-like at the tips. Nymphs resemble adults in shape but are often colored differently and do not have fully developed wings. Stink bugs (Pentatomidae) (Figure 3) are green [6 March 2013] or brown shield-shaped bugs 1/2 to 2/3 of an inch long. Eggs are barrel-shaped and found on the undersides of leaves in masses of 10 to 50. Nymphs are similar in shape to adults, but more brightly colored and patterned. Leaffooted bugs [6 March 2013] (Coreidae) (Figure 4) are dark-colored true bugs with parallel sides. Three species attack tomato in Florida, two of which have flattened hind tibia (lower legs). Eggs are metallic and ovate but somewhat flattened laterally and laid in clusters. Some leaffooted bugs lay their eggs end to end in a single row or chain along a stem or leaf midrib. Nymphs are oblong in shape and red, especially on the abdomen.

Figure 3. 

Green stink bug.


[Click thumbnail to enlarge.]

Figure 4. 

Leaffooted plant bug.


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Biology

Southern green stinkbug can complete its life cycle in 65 to 70 days. It overwinters as an adult in leaf litter, tree bark, and other protected sites. Weed hosts include beggarweed, rattlebox, Mexican clover, wild blackberry, and nutgrass. Leaffooted bugs also attack a wide variety of plants, although thistles and nightshade are principal hosts. Both stink bugs and leaffooted bugs emit a strong odor when disturbed.

Damage

Nymphs and adults of both stink bugs and leaffooted bugs suck juices from green fruit leaving a puncture which later may become surrounded by a discolored zone due to invasion of secondary pathogens. Stink bug feeding punctures are often surrounded with a lightened, sometimes depressed, blotch beneath the fruit surface caused by the removal of cell contents and the enzymes injected by the bug. Leaffooted plant bug punctures may cause fruit to become distorted as they enlarge. True bugs are occasional pests throughout Florida.

Western Flower Thrips, Frankliniella occidentalis, and Melon Thrips, Thrips palmi

Description and Biology

Adults of the western flower thrips and adults of the melon thrips are tiny (1/16 inch), slender, dark yellow insects with brown, fringed wings. They are most often located in flowers, but rarely occur in the terminal buds and leaves. The larvae are wingless, inhabiting primarily flowers and fruits. Two pupal stages do not feed, but fall to the ground. Thrips complete their life cycle in 15 to 30 days, depending on temperature. Western flower thrips and melon thrips have a broad host range. Western flower thrips feed and reproduce on tomato, pepper and eggplant. Tomato is not a suitable host for melon thrips, although pepper and eggplant are sometimes damaged. The western flower thrips occurs statewide in Florida, whereas damage to vegetables from melon thrips is restricted to southern Florida.

Figure 5. 

Thrips.


[Click thumbnail to enlarge.]

Damage

Eggs of the western flower thrips are inserted individually in tomato fruits, causing dimples, sometimes surrounded by a white area. Heavy dimpling can result in cullout and downgrading, depending on market conditions. Dimpling is very rare on pepper and eggplant. The adults and larvae of both the western flower thrips and the melon thrips feed by sucking the contents of the epidermal cells of the plant. When feeding, primarily by the larvae, occurs on fruit, it results in a damage symptom called "flecking." The western flower thrips is the key vector of Tomato spotted wilt virus. Tomato spotted wilt virus is the key pest problem in northern Florida. It is not a serious problem in central and southern Florida, although problems sometimes occur on late-planted fruiting vegetables.

Eastern Flower Thrips, Frankliniella tritici, Florida Flower Thrips, Frankliniella bispinosa, and Tobacco Thrips, Frankliniella fusca

The eastern flower thrips is the most common thrips in northern Florida. It does not occur in central and southern Florida. The Florida flower thrips is the most common thrips in central and southern Florida. Both species have biologies similar to western flower thrips and melon thrips. Adults of the eastern flower thrips and the Florida flower thrips are not associated with dimpling or flecking, even when their numbers exceed 15 or more per flower. Further, their reproduction on fruiting vegetables is much less than the western flower thrips, and the potential for larval 'flecking' damage is minimal. Populations of these native species are considered beneficial, as they outcompete western flower thrips. The tobacco thrips is another species native to Florida. It occurs rarely in fruiting vegetables, and usually in very low numbers.

Damage

Heavy infestations cause silvered or bronzed leaves, stunted leaves and terminals, and scarred and deformed fruit. On peppers, fruit scarring emanates from the stem end following crevices between locule lobes. Foliar damage may also be severe. Melon thrips also damages eggplant. Tomatoes are not affected.

Vegetable Leafminer, Liriomyza sativae, L. trifolii

Description and Biology

The adult is a small fly (Figure 6), approximately 1/8 inch long, with a black head, yellow between the eyes, a black thorax and a tube-like “ovipositor” at the end of the abdomen used to puncture the upper leaf surface for egg laying. The white, oval egg is inserted in the leaf tissue, but many punctures (called stipples) are used by the adult for feeding and do not contain eggs. The larva, a yellow maggot with black, sickle-shaped mouth hooks, feeds between the upper and lower leaf surface for approximately seven days, leaving a serpentine mine containing a string of black frass (fecal matter). The mature larva exits from the mine and falls to the ground (or plastic mulch) where it molts to a pupa within a golden brown, barrel-shaped, and ribbed puparium from which the adult emerges in seven to 14 days. Generation time is 15 to 28 days depending upon temperature.

Figure 6. 

Vegetable leafminer.


[Click thumbnail to enlarge.]

Damage

Leafminers reduce photosynthetic area and may provide entry points for foliar pathogens. Heavily damaged leaves become necrotic, predisposing fruit to sunscald. Vegetable leafminer may be an important pest in south and central Florida but is only an occasional pest in north Florida. It is not usually a serious pest of pepper or eggplant.

Tomato Pinworm, Keiferia lycopersicella

Description

The adult is a small gray moth (wing span about 1/2 inch) with a reddish-brown, mottled head and thorax. Eggs are pale yellow to orange, oval in shape, and are usually deposited singly or in groups of two to three on lower surfaces of foliage. Larvae (Figure 7) are purplish-gray, 3/8 inch long at maturity, and found inside blotch mines, leaf folds or fruit, usually around the stem attachment. The pupa is formed in a silken cocoon covered with sand particles near the soil surface or on the plastic mulch surface.

Figure 7. 

Tomato pinworm larva.


[Click thumbnail to enlarge.]

Biology

Moths are most active at dusk. The female emits an odor, or pheromone, which attracts males from long distances downwind for mating. After hatching, first instars spin silk over themselves and tunnel into the leaf. Third and fourth stages fold or tie leaves or feed in stems or fruit. The pupal stage can last 1 to 4 weeks. Total generation time varies from 21 to 67 days depending on temperature. Seven to eight overlapping generations a year occur in South Florida.

Damage

The tomato pinworm feeds only on solanaceous plants such as tomato, eggplant, and potato. Pepper is not a host. Heavy feeding on foliage may cause defoliation, but damage to fruit is usually the worst consequence of tomato pinworm infestations. Damaged fruits are contaminated with insect parts, silk and frass, and may rot from introduction of pathogens. The tomato pinworm is an important pest in the spring in south and central Florida and summer or late fall in North Florida, especially after populations have built up over the preceding season.

Tomato Fruitworm (Corn Earworm), Heliocoverpa zea

Description

The wingspan is about 1.5 inches. The forewing of the adult male is cream-colored with an orange or olive cast; the female is light yellow-brown with indistinct vertical lines. Eggs are waxy, white, dome-shaped and ribbed, with a flat base. They are deposited singly on the undersides of leaves or flower petals. Larvae (Figure 8) can vary in color from light green or pink to brown or nearly black and are lighter underneath. The body is marked with lengthwise alternating light and dark stripes. Spines have raised dark areas at their bases.

Figure 8. 

Tomato fruitworm (corn earworm) larva.


[Click thumbnail to enlarge.]

Biology

Adults are active at night. Eggs hatch in 2 or 3 days and the larval stage lasts 14–21 days. Larvae move to green fruit soon after hatching, where they bore deeply into the fruit. Tomato fruitworm pupates in the soil; the adult emerges in 7 to 14 days.

Damage

Larvae chew large deep holes in tomato fruit, especially at the stem end. They occasionally feed on foliage. Eggplant and pepper fruits may also be damaged by tomato fruitworm.

Southern Armyworm, Spodoptera eridania

Description

The adult is relatively large (1.5-inch wingspan) with the front wing streaked with cream, gray, light brown and black and the hindwing white with some dark on the margins. Eggs are laid on the undersides of leaves in large masses of 100 to 200, covered with a felt-like mat of body hair. Eggs which hatch in about three to four days. Larvae are dark caterpillars, two yellowish lateral lines interrupted by a large dark spot on the first abdominal segment (Figure 9). Large larvae have two rows of dark triangles on the dorsal surface. The generation time is 29 to 35 days. Southern armyworm is the most common armyworm pest of tomato in south and central Florida but is only an occasional pest in north Florida.

Figure 9. 

Southern armyworm larva.


[Click thumbnail to enlarge.]

Beet Armyworm, Spodoptera exigua

Description

The adult is smaller than southern armyworm, (wingspan one inch) with the front wing light brownish gray with indistinct lines and the hindwing white. Egg masses are also smaller than southern armyworm, numbering usually 50 to 75 eggs but are otherwise similar. Larvae (Figure 10) are generally green, mottled with white spots, one to 1¼ inch long at maturity and often with a small black spot above the second pair of true legs. Generation time 25 to 35 days. Tomato is not a preferred host for beet armyworm but the insect may occasionally reach damaging levels anywhere in the state. Pepper is a preferred host, and larvae may feed on buds, silk leaves together, or may bore into fruit. The beet armyworm is more difficult to control than the southern armyworm.

Figure 10. 

Beet armyworm larva.


[Click thumbnail to enlarge.]

Yellowstriped Armyworm, Spodoptera ornithogalli

Description

The adults and eggs are similar to the southern armyworm. Yellowstriped armyworm larvae (Figure 11) have dark heads and dark lateral marks bisected by a thin, white line on each segment behind the true legs. The yellowstriped armyworm is a serious pest in north Florida during the fall but is rarely present in south and central Florida.

Figure 11. 

Yellowstriped armyworm larva.


[Click thumbnail to enlarge.]

Pepper Weevil, Anthonomus eugenii

Description

The adult (Figure 12) is a small (1/6 inch) black or gray beetle with a long snout (proboscis) and elbowed antennae. Larvae are tiny, legless grubs, found inside the pepper fruit.

Figure 12. 

Pepper weevil larva and adult.


Credit: F. Drummond, University of Maine
[Click thumbnail to enlarge.]

Biology

Adults use the mandibles at the end of the proboscis to feed on leaf or flower buds. Females also use the mandibles to bore a small hole in developing fruit or flower buds. The hole is plugged with fecal matter (frass) after an egg is deposited. A tiny legless grub hatches from the egg and eats its way toward the seed core of the fruit where it feeds on seeds and pulp, passing through larval growth stages or instars. Pupation takes place inside the fruit within a small cell created by larval feeding. The emerging adult may feed within the fruit for awhile before escaping through a circular hole chewed in the wall of the fruit.

Black nightshade can serve as a secondary host to maintain small numbers of pepper weevil during fallow periods. Because development times decrease as temperature increases and because adults will migrate readily from old fields to new plantings, populations generally build up during the season so that populations are greatest in later spring plantings.

Damage

Damaged fruit become contaminated by insect parts, frass and rotted tissue, and will eventually fall from the plant.

Broad Mite, Polyphagotarsonemus latus

Description and Biology

Adults (Figure 13) are tiny, white, eight-legged mites and are usually most numerous on the underside of young, emergent foliage. Males can sometimes be seen carrying females “piggyback." Nymphs are similar though somewhat smaller than adults are. Eggs are about 1/4 the size of adults, round with white, opalescent spots, and glued to the plant surface. Generation time may be as short as 5 days, depending on temperature.

Figure 13. 

Broad mite.


[Click thumbnail to enlarge.]

Damage

In peppers, broad mite feeding distorts plant tissue, causing leaves to become thickened and narrow, giving them a “strappy” appearance. Heavy feeding causes flower abortion and dark, smooth russeting of fruit. Infestations are often spotty, but may become more generalized, especially in late fall. Broad mite is a major pest of pepper and eggplant.

Colorado Potato Beetle, Leptinotarsa decemlineata

Description

Adults (Figure 14) have 10 lengthwise black stripes on yellow-orange wing covers and are approximately 3/8 inch long by 1/4 inch wide. They are distinctly convex in shape. Clusters of 10 or more yellow to orange spindle-shaped eggs can be found on the undersides of leaves. The larvae are humpbacked, red to orange, and have two rows of black spots on each side of their soft bodies.

Figure 14. 

Colorado potato beetle larva and adult.


[Click thumbnail to enlarge.]

Biology

Colorado potato beetle is primarily a pest in the northern half of the state. Adults will overwinter in debris around the edges of fields planted the previous season with potatoes, eggplant, or tomatoes. In the spring, they lay eggs in clusters of 10 – 40 that will hatch in 3 to 7 days, depending on temperature. Females may deposit over 300 eggs over a 4-to 5-week period. Larvae complete 4 instars while feeding on leaves for two to three weeks and drop to the soil to pupate. New adults emerge from the soil 5 to 10 days later, or longer, depending on temperature. Colorado potato beetle attacks primarily potatoes, eggplant, and tomatoes, but it will also feed on peppers, tobacco, and solanaceous weeds, such as nightshade, horse-nettle, and ground cherry.

Damage

They are voracious leaf feeders and will totally defoliate plants.

References

Gillett, J. L., H. N. HansPetersen, N. C. Leppla, and D. D. Thomas. 2006. Grower’s IPM Guide for Florida Tomato and Pepper Production. Gainesville: University of Florida Institute of Food and Agricultural Sciences. http://ipm.ifas.ufl.edu/resources/success_stories/T&PGuide/

Pernezny, K., D. Schuster, P. Stansly, G. Simone, V. Waddill, J. Funderburk, F. Johnson, R. Lentini and J Castner. 1996. Florida Tomato Scouting Guide with Insect and Disease Identification Keys. SP-22 Gainesville: University of Florida Institute of Food and Agricultural Sciences. http://erec.ifas.ufl.edu/tomato-scouting-guide/

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Tables

Table 1. 

Silverleaf Whitefly

Management Option

Recommendation

Scouting/ thresholds

For tomatoes, examine six feet of row (a sample) for every 2.5 acres. When plants have three or fewer true leaves, examine six plants per sample for adult whiteflies. If plants have more than three leaves, examine the terminal leaflet of the third leaf from the top of the stalk. For nymphs, examine a terminal leaflet from the third leaf from the top until seven leaves are present and from the seventh leaf from the top thereafter. Look at six leaflets per six feet of row and calculate an average per leaflet. Tentative thresholds are 0.5 pupae or nymphs per leaflet or 10 adults per plant (0-3 true leaves) or 1 adult per leaflet (over 3 true leaves).

Note(s)

Soil application of a systemic, nicotinoid insecticide at crop initiation controls whiteflies well and reduces virus spread. To avoid the development of resistance to this insecticide, it is recommended that applications be made to the earliest “at risk” plantings using the lowest labeled rate. Fields should be scouted to determine the need for additional applications, using a different active ingredient, preferably an insect growth regulator or other selective material.

Mulches

Reflective aluminum mulches may reduce virus spread by deterring adult whiteflies from landing on plants.

Natural enemies

Parasitic wasps, lady beetles, lacewings, minute pirate bugs, fungi, particularly when whiteflies are developing on weeds.

Cultural controls

Tomato is the major source of whitefly-transmitted viruses, so attention should be paid to the probable source of whiteflies invading a field, given that highest risk is from senescing, abandoned or 'volunteer' tomatoes.

A two-month or more crop-free period will reduce virus and whitefly populations.

Table 2. 

Aphids

Management Option

Recommendation

Scouting/ thresholds

For tomatoes, examine six feet of row (a sample) for every 2.5 acres. When plants have two or fewer true leaves, examine six plants per sample for aphids. If plants have more than three leaves but are not yet blooming, examine the terminal three leaflets (trifoliate) of the third expanded leaf from the top of the main stem. After bloom, examine the terminal trifoliate of the seventh leaf from the tip of any branch. Look at six trifoliates per six feet of row and calculate an average per trifoliate. Treat with appropriate insecticides if aphids reach 3 to 4 per plant.

Note(s)

Insecticides will not slow the spread of most aphid-transmitted plant viruses. Certain mineral oil formulations, if applied strictly according to the label before 5%-10% infection, may delay spread of these viruses by interfering with the attachment of virus to the aphid's mouthparts.

Mulches

Reflective aluminum mulches will deter aphids from landing on plants. The effect is lost once plants are large enough to cover the mulch.

Natural enemies

Parasitic wasps, ladybird beetles, syrphid fly larvae, and lacewing larvae attack aphids that reproduce on the crop. In humid weather, fungi may kill many aphids.

Table 3. 

True Bugs

Management Option

Recommendation

Scouting/ thresholds

After fruit set, examine 10 fruit per 6-foot section of row for each 2.5 acres. If there is more than one stink bug per six plants, apply insecticide.

Natural enemies

Several species of parasitoid wasps attack eggs of leaffooted bugs. Insect predators also consume eggs. A tachinid fly parasitizes stink bug nymphs and adults, and a wasp parasitizes eggs.

Cultural controls

Trap crops (cowpeas and beans in summer, cruciferous plants in early spring and fall) may have some value. The trap crop should be sprayed before stink bug nymphs become adults. Weed management in and around the field prior to planting the crop is important.

Table 4. 

Western flower thrips and melon thrips

Management Option

Recommentation

Scouting/ thresholds

Distinguish between adult and larval thrips and identify adult thrips to species. Examine at least 10 flowers and 10 small fruits for every 2.5 acres. Place flowers and fruit on white board to observe the thrips as they crawl out. Open flowers and remove the calyx on small fruit. In tomato, treat if there are more than 1 adult western flower thrips per flower. In pepper and eggplant, treat if there are more than 6 adult western and melon thrips per flower. In tomato, pepper and eggplant, treat when larval numbers exceed 2 per small fruit. Do not treat for eastern flower thrips and Florida flower thrips.

Natural enemies

Minute pirate bugs are predators of thrips with natural populations usually sufficient in pepper and eggplant to control thrips, if a conservation biological control program is employed. When peppers and eggplants are flowering be careful to choose insecticides for thrips and other insect pest control when peppers and eggplants are flowering that have minimal impact on minute pirate bug populations. Sunflower and other refugia plants provide a source for minute pirate bugs.

Cultural practices

Use ultra-violet reflective mulches when forming beds for control of thrips and Tomato spotted wilt virus. Do not overfertilize because thrips prefer and perform better on plants that are over-fertilized.

Notes

Certain insecticides, especially pyrethroids, enhance western flower thrips and melon thrips. They should not be used on pepper and eggplant, and they should be avoided on tomato. Please note that many insecticides have a generic label for thrips, but they do not control the western flower thrips or the melon thrips. Some even enhance their populations either directly or by killing minute pirate bugs and competitor thrips.

Table 5. 

Vegetable Leafminer

Management Option

Recommendation

Scouting/ Thresholds

For tomatoes, examine six feet of row (a sample) for every 2.5 acres. When plants have two or fewer true leaves, examine six plants per sample for leafminers. If plants have three to seven leaves, examine the terminal three leaflets (trifoliate) of the third expanded leaf from the top of the main stem. After seven leaves are present, examine the terminal trifoliate of the seventh leaf from the tip of any branch. Look at six trifoliates per six feet of row and calculate an average per trifoliate. Treat with appropriate insecticides if the average is 0.7 larvae per plant (0–2 true leaves) or 0.7 larvae per 3 terminal leaflets (>2 leaves per plant).

Note(s)

Insecticides applied for leafminer control should target small larvae for best results.

Natural enemies

A number of parasitic wasps attack vegetable leafminer in Florida and may provide high levels of mortality, especially late in the season. Therefore, insecticides with low or no toxicity to leafminer parasites should be selected for controlling leafminers and other pests.

Table 6. 

Tomato Pinworm

Management Option

Recommendation

Scouting/ Thresholds

Count the number of larvae on the foliage of whole plants (up to 7th true leaf stage), or on one leaf selected from the lower canopy of each plants (from 8th true leaf to end of crop). Treat if the following thresholds are reached: 0.7 larva per plant (0-7 leaves), 0.7 larva per leaf (>7 true leaves). Also treat with pheromone for mating disruption if 5 or more moths are caught per night in a pheromone trap.

Note(s)

Mating disruption by application of commercially available pheromone preparations is preferred over insecticidal control in order to conserve parasites and predators of tomato pinworm.

Cultural controls

Use clean transplants, separate plantings from previous crops of tomato, eggplant, or potato. Field sanitation and destruction of crop residue from previous plantings is important for reducing summer populations.

Table 7. 

Tomato Fruitworm (corn earworm)

Management Option

Recommendation

Scouting/ Thresholds

Examine 6 feet of row for every 2.5 acres. Concentrate on areas where there is evidence of feeding (leaves, fruit). Examine the undersides of leaves adjacent to flowers for eggs. Treat if there is one larva or more per six plants before bloom; after bloom, treat if one egg or larva is found per field. Pheromone traps, placed on the edge of the field, have been useful for monitoring purposes in the Midwest.

Note(s)

Insecticides must be present on plants when eggs hatch so that newly hatched larvae will contact a lethal dose.

Natural enemies

General predators, such as big-eyed bugs and pirate bugs, feed on eggs. Parasitoid wasps attack eggs and larvae.

Table 8. 

Management of Beet, Southern, Fall and Yellowstriped Armyworms

Management Option

Recommendation

Scouting/ Thresholds

Examine 6 feet of row for every 2.5 acres. Concentrate on areas where there is evidence of feeding (leaves, fruit). Treat if there is one larva or more per six plants before bloom; after bloom, treat if one egg or larva is found per field.

Note(s)

Younger larvae are always easier to control than older larvae, especially when using Bacillus thuringiensis (Bt) products.

Natural enemies

Many natural enemies attack armyworms, including parasitoid wasps and tachinid flies. General predators feed on eggs and small larvae.

Table 9. 

Pepper Weevil

Management Option

Recommendation

Scouting/ Thresholds

Because adults tend to move to lower, more protected and less visible plant parts as temperatures increase, scouting efforts should concentrate on a search for adults in leaf whorls, flowers, and fruit during morning hours. Commercially available pheromone traps may also aid in early detection. Fruit and flower buds should be examined for damage and fallen fruit and buds examined for presence of larvae.

Note(s)

Chemical control is difficult because all stages except the adult are protected within the fruit, so that only the adult weevil is vulnerable to insecticides. Frequent sprays may be necessary starting in the initial stages of infestation, usually pre-bloom, in order to avoid unacceptable levels of damage.

Natural enemies

A few parasites and predators are known to attack the weevil, but are not thought to be a factor in suppressing populations.

Cultural controls

If possible, all damaged and fallen fruit should be removed and destroyed. Adjacent or nearby sequential plantings should be avoided. Crops should be deep-plowed immediately following harvest and after treating with insecticide to reduce adult movement into nearby fields and to reduce survival over the summer. Nightshade in and around fields should be controlled to reduce population survival between crops.

Table 10. 

Broad Mite

Management Option

Recommendation

Scouting/ Thresholds

None currently available for Florida. Infestations occurring during at or before the early fruiting stage of peppers cause the most damage.

Note(s)

Chemical control is not difficult but should be timely. Heavy infestation may require two applications five days apart to allow time for eggs to hatch. Specific acaricides are usually recommended over broad-spectrum acaricide/insecticides to better conserve beneficial insects.

Natural enemies

General mite predators can be effective.

Table 11. 

Colorado Potato Beetle

Management Option

Recommendation

Scouting/ Thresholds

There are no thresholds for Florida. Other states recommend examining at least 30 plants per field and treating if more than 1 adult, larva, or egg mass per plant is found (average of 30 plants).

Note(s)

Insecticide resistance is a major problem in other parts of the country.

Natural enemies

Good results have been obtained with a tiny wasp that parasitizes eggs. The wasp, Edovum puttleri, was introduced from South America and mass-reared for release in the Northeast.

Cultural practices

Rotation with non-host plants, such as corn, is effective, because beetles are weak fliers. Plant at least 1/2 mile away from a previously infested field. Potatoes can be used as a trap crop for tomatoes. One or two rows of potatoes planted 20 to 30 days before tomatoes will attract adult beetles, which can then be killed with insecticides before they move into the tomatoes.

Footnotes

1.

This document is ENY-461, one of a series of the Department of Entomology and Nematology, UF/IFAS Extension. Original publication date November 2001. Revised May 2010, June 2013, and February 2017. Visit the EDIS website at http://edis.ifas.ufl.edu.

2.

S. E. Webb, associate professor; P. A. Stansly, professor; D. J. Schuster, professor; J. E. Funderburk, professor; and H. Smith, assistant professor; Department of Entomology and Nematology, UF/IFAS Extension, Gainesville, FL 32611.

The use of trade names in this publication is solely for the purpose of providing specific information. UF/IFAS does not guarantee or warranty the products named, and references to them in this publication does not signify our approval to the exclusion of other products of suitable composition. All chemicals should be used in accordance with directions on the manufacturer's label. Use pesticides safely. Read and follow directions on the manufacturer's label.


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.