There are over 35 insects and mites that attack peppers and more than 50 diseases. Fortunately, most of these are rare or minor problems or don’t occur in our growing area. In Part 3A, we will look at some of the more common pests that you may encounter on your peppers in your vegetable garden. Next month in Part 3B we will look at pepper diseases.

Pests: Aphids Green Peach Aphid Myzus persicae, Melon Aphid Aphis gossypii (Figure 1). The adult green peach aphid is light to dark green or pink with red eyes and three dark lines may be visible running down its back. The adult melon aphids are 1-2 mm long and come in a range of colors that include light yellow, green, dark green, or almost black. Regardless of the body color, melon aphid cornicles will always be dark. Aphids can be controlled with insecticidal soaps, horticultural oils, malathion, bifenthrin, or imidacloprid.

Figure 1: Left Picture – Melon Aphid Aphis gossypii – A: Dark blackish form; B: Alternate color form; C: Winged adult; D: Light color form showing cornicles. Note the cornicles are dark in all color forms. Right Picture – Green Peach Aphid Myzus persicae. A: Wingless adult showing cornicles with dark tips; B: Winged adult; C: Adult giving birth to nymph; D: Alternate color form.

Beet armyworm Spodoptera exigua (Figure 2). The mature larva can be variable but is generally a light green to black larva with four pairs of abdominal prolegs and a dark head. There are many fine, white wavy lines along the back and a broader stripe along each side. There is usually a distinctive dark spot on each side just above the second pair of true legs. Beet armyworms can be controlled with BT, Spinosad, permethrin, and cyfluthrin.

Figure 2: Beet Armyworm (Spodoptera exigua) lifecycle. : -Eggs; B: Young instars feeding in mass; C: Mature larva showing variation; D: Mature moth with wings open and wings folded.

Colorado potato beetle Leptinotarsa decemlineata (Figure 3). The adults measure about 3/8 inch long and are yellowish-orange with multiple black stripes down the back. The head has a triangular black spot and the thorax has irregular black markings. The small, plump, reddish larvae of the Colorado potato beetle are ½” long when mature with two rows of black spots down their sides. Picking the larvae and adults off of plants manually can control populations in small garden plots. Colorado potato beetle can be controlled with insecticides such as azadirachtin (neem) and Figure 1: Left Picture – Melon Aphid Aphis gossypii – A: Dark blackish form; B: Alternate color form; C: Winged adult; D: Light color form showing cornicles. Note the cornicles are dark in all color forms. Right Picture – Green Peach Aphid Myzus persicae. A: Wingless adult showing cornicles with dark tips; B: Winged adult; C: Adult giving birth to nymph; D: Alternate color form. Figure 2: Beet Armyworm (Spodoptera exigua) lifecycle. : -Eggs; B: Young instars feeding in mass; C: Mature larva showing variation; D: Mature moth with wings open and wings folded. Spinosad. Strains of Bacillus thuringiensis can be used to control larvae. Colorado potato beetle is resistant to many commonly used chemical insecticides such as carbaryl, permethrin, pyrethrin, and imidacloprid.

Figure 3: Colorado Potato Beetle Leptinotarsa decemlineata. A: Egg mass. B: Larva. C: Adult

Vegetable Leafminers Lyriomyza sativae (Figure 4). The adults are principally yellow and black. Females are larger than males, and have an elongated abdomen. They have a wing length of 1.25 to 1.7 mm, with the males averaging about 1.3 mm and the females about 1.5 mm. In warm climates they may breed continuously, with many overlapping generations per year. Mature larvae are about 2.25 mm long. Initially the larvae are nearly colorless, becoming greenish and then yellowish as they mature. Leafminers generally don’t cause sufficient damage to warrant control measures. Contact insecticides aren’t effective against larvae once they are inside the leaf. Systemic insecticides like imidacloprid can be effective if infestation is severe.

Figure 4: Vegetable Leafminer Lyriomyza sativae. A: Adult. B: Mature larva. C: Tunnels on pepper leaves.

Tomato fruit worm (Corn earworm) Helicoverpa zea (Figure 5). Full-grown larvae of the corn earworm are olive-brown, tan, maroon, pink, or black with three or four dark stripes along their backs. The head is yellow and not spotted. Mature larvae may be up to 2 inches long. Adults moths are grayish-brown with a wing-span of 1 ½”. The front wings are marked with dark gray, irregular lines with a dark area near the wing tip. Damage is often visible as a small hole near the fruit stem. The larva can be found feeding inside the fruit. Bt, carbaryl, and permethrin can be used as a treatment before the larva enters the fruit. Insecticides must be present on plants when eggs hatch so that newly hatched larvae are killed before entering the protection of the fruit.

Figure 5: Tomato Fruit Worm/Corn earworm (Helicoverpa zea) A: Young larva feeding inside fruit. B: Mature larva feeding on leaves.

Pepper weevil Anthonomus eugenii (Figure 6). The adult is a 1/6” long black or gray beetle with a long snout (proboscis) and L-shaped antennae. The tiny, legless larvae are found inside the pepper fruit. Insecticides recommended for pepper weevil contain carbaryl or malathion. Chemical control is difficult because all stages except the adult are protected within the fruit. Only the adult weevil is exposed to insecticide sprays.

Figure 6: Pepper Weevil A: Adult weevil (note the proboscis). B: Small white larva inside fruit.

Thrips Western flower thrips Frankliniella occidentalis, Onion thrips Thrips tabaci, Chili thrips Scirtothrips dorsalis (Figure 7). Adult thrips are elongate, slender, and tiny (less than 1/20” long), with fringes on the margins of both pairs of their long, narrow wings. Immatures are similar in shape to the adults but lack wings. Most thrips range in color from translucent white to yellowish to brown. Thrips damage results in feeding scars, leaf distortion, and discoloration of buds, flowers and young fruits. Thrips control recommendations include the use of systemic insecticides containing imidacloprid. Contact insecticides like insecticidal soap, and horticultural oil may be effective but attaining good coverage is difficult due to the small insect size and feeding locations.

Figure 7: Thrips A: Western flower thrips Frankliniella occidentalis B: Onion thrips Thrips tabaci C: Chili thrips Scirtothrips dorsalis D-F: Damage caused by thrips feeding.

Whiteflies Solanum Whitefly Aleurotrachelus trachoides, Silverleaf (Sweetpotato) Whitefly Bemisia tabaci, Greenhouse Whitefly Trialeurodes vaporariorum (Figure 8). Whitefly adults are tiny (0.06 inch, 1.5 mm long), yellowish insects with white wings. Whiteflies are found mostly on the undersides of leaves. They fly readily when plants are disturbed. Whiteflies damage peppers by feeding on the sap weakening the plant and by producing honeydew that provides food for black sooty mold. Sooty mold grows on the honeydew which can cover a large proportion of the plant; thus, lowering the photosynthetic capacity of the plant and making the fruit unattractive Because whiteflies are easily disturbed, control using contact insecticides is spotty. Use of systemic insecticides like imidacloprid are more effective.

Figure 8: Whiteflies. A: Solanum Whitefly Aleurotrachelus trachoides B: Silverleaf (Sweetpotato) Whitefly Bemisia tabaci C: Greenhouse Whitefly Trialeurodes vaporariorum D: Mass of whiteflies on leaf underside

Flea Beetles Potato Flea Beetle Epitrix cucumeris, Tobacco Flea Beetle Epitrix hiritipennis, Palestriped Flea Beetle Systena blanda (Figure 9). Flea beetle adults are small (about 0.125 inch long), shiny, hard beetles with enlarged hind legs that allow them to jump. Adult flea beetles feed on the undersides of leaves leaving small pits or irregularly shaped holes on the leaves. Large populations can kill or stunt seedlings. Older plants rarely suffer economic damage, although their older, lower leaves may be damaged. Adults do most of the damage. Most flea beetle larvae feed on roots, but this does not warrant concern in peppers usually. If insect population and plant age warrant control measures, insecticides containing dinotefuran, permethrin, bifenthrin, or carbaryl have been shown to be effective. If insect population and plant age warrant control measures, insecticides containing dinotefuran, permethrin, bifenthrin, or carbaryl have been shown to be effective.

Two spotted spider mite Tetranychus urticae (Figure 10). Two-spotted spider mites are 1/50 inch long, with a green-yellow translucent color. The two large spots in the body are accumulated waste, so may not be present during early stages. The two-spotted spider mite produces a web containing the eggs that hatch after 3 days. These spider mites live mainly on the undersides of leaves and damage the plant by feeding with their piercing-sucking mouthparts. Feeding injury often gives the top leaf surfaces a mottled or speckled appearance. Spider mite feeding causes yellowing of the leaves that eventually die and drop off the plant. Miticides containing abamectin or bifenazate have been shown to be effective against spider mites. Contact pesticides like insecticidal soaps and neem oil have also been effective but getting adequate coverage is difficult. Insecticides containing pyrethrins should not be used because they have been shown to increase spider mite reproduction and can lead to population explosions.

Figure 11: Broad Mite Polyphagotarsonemus latus A: Adult mites, mite eggs, and young mite. B: Damage caused by broad mite feeding on pepper.

Figure 12: Nematodes. A: Typical symptoms of nematode damage to roots. Top row are healthy peppers. Bottom row are infected peppers. B-D: Nodules and root damage caused by root knot nematode.

Broad Mite Polyphagotarsonemus latus (Figure 11). Adults are 1/100 inch long, white, eight-legged mites found mostly on the underside of young foliage. Generation time may be as short as 5 days, depending on temperature. In peppers, broad mite feeding distorts plant tissue, causing leaves to become thickened and narrow, giving them a straplike appearance. Heavy feeding causes flower loss and dark, smooth russeting on the fruit. Broad mite control using insecticidal soaps and horticultural oils is very effective if adequate coverage is achieved. Acaricides containing abamectin, spirotetramal, or Pylon are also effective against broad mites. Nematodes Southern Root Knot Meloidogyne incognito, Guava Root Knot Meloidogyne enterolobii, Reniform Nematode Rotylenchulus reniformis (Figure 12). The reniform nematode causes root necrosis resulting in severe root pruning and subsequent dwarfing of plants. Fibrous or feeder roots are mostly attacked which may reduce the absorption ability and other physiological functions of the plant. This may lead to stunting, yellowing and wilting. Currently available recommended nematicides are “Restricted Use”; therefore, the most effective management practices available to home gardeners are crop rotation, soil solarization, and resistant varieties.

~ Dr. Joe W. Willis

Resources:

Capinera, J.L. 2020. Vegetable Leafminer. UF/IFAS. EENY-255. vegetable leafminer - Liriomyza sativae Blanchard (ufl.edu) Chilli Thrips. 2024. UF/IFAS Extension. Chilli Thrips – Gardening Solutions (ufl.edu) Fasulo, T.R. 2022. Broad Mite Polyphagotarsonemus latus. UF/IFAS EENY-183. EENY-183/IN340: Broad Mite, Polyphagotarsonemus latus (Banks) (Arachnida: Acari: Tarsonemidae) (ufl.edu) Jacques, R.L. Jr. 2020. Colorado Potato Beetle. UF/IFAS Featured Creatures. EENY-146. Colorado potato beetle - Leptinotarsa decemlineata (Say) (ufl.edu) Kumar, V. et. al. 2017. Solanum Whitefly, Pepper Whitefly. UF/IFAS EENY-662. EENY662/IN1159: Solanum Whitefly, Pepper Whitefly (Suggested Common Names) Aleurotrachelus trachoides Back (Insecta: Hemiptera: Aleyrodidae: Aleyrodinae) (ufl.edu) Martini, X., J.E. Funderburk, S.E. Webb, & H. Smith. 2021. Arthropod Management for Tomato, Pepper and Eggplant. UF/ IFAS ENY-461. ENY-461/IN169: Arthropod Management for Tomato, Pepper, and Eggplant (ufl.edu) Natwick, E.T. et. al. 2016. Flea Beetles. UC-IPM. Pub. 3460. Flea Beetles / Peppers / Agriculture: Pest Management Guidelines / UC Statewide IPM Program (UC IPM) (ucanr.edu) Natwick, E.T. et. al. 2013. Whiteflies. UC-IPM. Pub. 3470. Whiteflies / Tomato / Agriculture: Pest Management Guidelines / UC Statewide IPM Program (UC IPM) (ucanr.edu) Noling, J.W. 2023. Nematode Management in Tomatoes, Peppers and Eggplant. UF/IFAS. ENY-032/NG032: Nematode Management in Tomatoes, Peppers, and Eggplant (ufl.edu) Overstreet, C. & D. Xavier. 2016. Nematodes on Vegetables. Nematodes on vegetables (lsuagcenter.com) Overstreet, C. et. al. 2018. Guava Root-Knot Nematode - A Potentially Serious New Pest In Louisiana. guava-root-knotnematode-adapdf.pdf (msfb.org) Ploeg, A.T. 2016. Nematodes. UC-IPM. Nematodes / Peppers / Agriculture: Pest Management Guidelines / UC Statewide IPM Program (UC IPM) (ucanr.edu) Rusnak, P. 2023. Invasive Pepper Thrips Could Become a Major Pain for Growers in Florida. Invasive Pepper Thrips Could Become a Major Pain for Growers in Florida - Growing Produce Sorensen, K., J. Baker, C.C. Carter, and D. Stephan. 2024. Pests of Peppers. NC State Extension. AG-295. Pests of Peppers | NC State Extension Publications (ncsu.edu) Wang, K-H. 2019. Reniform Nematode. UF/IFAS. reniform nematode - Rotylenchulus reniformis (ufl.edu)