A solanaceous crop related to the nightshade family of plants, eggplant has some of the same pests as pepper, potato, and tomato. The eggplant flea beetle and the eggplant lace bug are common pests, but twospotted spider mites can be more damaging.

Chewing insects that feed on aboveground plant parts
1. Beetles—Chewing insects with hard, shell-like forewings that meet in a straight line down the middle of the back. Beetles chew holes in foliage.
  1. Colorado potato beetle—This insect has a yellowish-brown, oval body that is 3/8 to 9/16 inch long. It has black spots on the pronotum (area behind the head) and five black stripes on each wing cover (Figure 1). The beetle feeds on terminal buds and may consume entire leaves. (For more information about Colorado potato beetles, see “Pests of Potato.”)
  2. Eggplant flea beetle—Black with a slightly hairy, oval body and black legs, this beetle is a little more than 1/16 inch long. The antennae are one-half to two-thirds the length of the body. The hind legs are modified for jumping. They leave tiny "shot holes" in foliage (Figure 2A).
  3. Potato flea beetle—Brownish-black to black, this beetle is almost 1/8 inch long. It is much less hairy than the eggplant flea beetle. The antennae are one-half to two-thirds the length of the body. The hind legs are modified for jumping. Flea beetles leave tiny "shot holes" in foliage (Figure 2B). (For more information about potato flea beetles, see “Pests of Potato.”)
  4. Colorado potato beetle larva—The larva is a soft-bodied, chewing insect that may grow to almost 5/8 inch long. It is red, yellowish red, or orange, with a black head, three pairs of black legs, and two rows of black spots on each side of the body. It has one pair of fleshy prolegs on the last abdominal segment (Figure 3). Like the adult beetle, it chews holes in leaves and buds. (For more information about Colorado potato beetles, see “Pests of Potato.”
Pests with needlelike mouthparts that feed on aboveground plant parts and extract plant juices
1. Eggplant lace bug —Grayish to light brown in color, adult eggplant lace bugs (Figure 4A) cluster in herds along with spiny, yellow nymphs (Figure 4B). Adults are almost 3/16 inch long and a little more than 1/16 inch wide, with two pairs of lacelike wings and a hoodlike projection just behind or over the head. They feed in colonies on the undersides of leaves. The tops of infested leaves have roughly circular discolored areas.
2. Twospotted spider mite—Tiny (almost microscopic) and pale to dark green, this pest has two or four dark spots (Figure 5). Adults and nymphs have eight legs. Larvae have six legs. Females are oval and about 1/64 inch long. Males taper toward the rear. All stages occur on undersides of leaves. Infested foliage has silvery or pale-yellow stipples. The leaves eventually become pale, then bronze, and finally dry up. Mites spin silken webs on the undersides of leaves as they feed. (For more information about twospotted spider mites, see “Pests of Beans and Peas.”)
Soft-bodied, root-feeding pests
1. Flea beetle larvae—The larvae of most species of flea beetles are cylindrical and whitish with a brown head, three pairs of legs near the head, and a pair of anal prolegs. They grow up to 3/16 inch long (Figure 6). (For more information about flea beetles, see “Pests of Potato.”)

Top view of oval beetle. Prominent longitudinal stripes on folded, outer wing covers. Various dark spots on thorax. Black and white art.

Figure 1. Colorado potato beetle.

Illustration by Ponglerd Kooaroon.

Top view of oval beetle with six legs, two antennae, and ridged, wing covers folded over back. Black and white art.

Figure 2A. Eggplant flea beetle.

Illustration by USDA.

Top view of uniformly dark, oval beetle with six legs, two antennae, and ridged wing covers folded over back. Black and white art.

Figure 2B. Potato flea beetle.

Illustration by USDA.

Side view of short, humpbacked grub with four rows of dark spots along side. Black and white art.

Figure 3. Colorado potato beetle larva.

Illustration by Ponglerd Kooaroon.

Top view of adult with paddle-shaped forewings folded straight back over body with many cells that suggest transparent lace. Black and white art.

Figure 4A. Eggplant lace bug adult.

Illustration by Susan Van Gieson.

Top view of oval-bodied nymph with prominent spines on abdomen. Two round light areas behind thorax are the developing wing pads. Black and white art.

Figure 4B. Stage four eggplant lace bug nymph.

Illustration by Susan Van Gieson.

Female and male mites, resting stages, first stage (larva), second stage (nymph), third stage (nymph) and several eggs. Black and white composite drawing.

Figure 5. Twospotted spider mites.

Illustration by J.R. Baker, NC State.

Side view of very slender larva with small pointed head and posterior. Black and white line art.

Figure 6. Flea beetle larva.

Illustration by Ponglerd Kooaroon.

Eggplant Flea Beetle

Epitrix fuscula Crotch, Chrysomelidae, COLEOPTERA

Description

Adult—This black, oval beetle is a little more than 1/16 inch long and has thickened hind legs for jumping. Its antennae are two-thirds the length of its body. This species resembles the potato flea beetle but has black legs and slightly hairy wing covers (Figure 7A).

Egg—Generally elliptical in shape, the egg is extremely small and pointed at one end. Though white at first, it gradually becomes yellowish gray.

Larva—A typical flea beetle larva is white with a brown head and has three pairs of brown legs near its head (Figure 7B). This species is up to 3/16 inch long when fully grown.

Pupa—Shaped essentially like adults, pupae are found in the soil. They are white at first but gradually darken (Figure 7C).

Biology

Distribution—Occurring throughout most of the United States, eggplant flea beetles tend to be most common in southern states.

Host Plants—This flea beetle has few known host species. Reports of its occurrence have been limited to eggplant, potato, horsenettle, pokeweed, sugar beet, and strawberry.

Damage—Feeding on new spring growth, eggplant flea beetles can be very destructive to young plants. They riddle foliage with holes (Figure 8), cause leaf edges to turn brown, and give plants a diseased appearance. Though older leaves often withstand injury, younger leaves may die. The larvae feed on roots and may cause damage to tuber crops such as beet and potato.

Life History—Eggplant flea beetles overwinter as adults in soil or crop debris. Their life cycle has not been studied in North Carolina, but in Indiana they are known to emerge from hibernation in mid- to late March. They infest weedy hosts such as horsenettle and pokeweed until crop hosts become available. Eggs laid in soil near the bases of plants hatch in about one week. Larvae emerge from the eggs and feed on roots or tubers for two to three weeks. After developing through three instar stages, larvae pupate in the soil. The pupal stage lasts seven to ten days. Beetles emerge from the pupal skins, make their way out of the soil, and feed on leaves for two months or more. Flea beetles complete one to four generations each year. In North Carolina, there are probably three or four annual generations.

Control

Cultural practices such as destroying crop residue, controlling weeds, and planting late help minimize flea beetle problems. Removing crop residue reduces the number of favorable overwintering sites for flea beetles. Covering plant beds and destroying trash around them also are beneficial. Controlling weeds such as horsenettle and pokeweed around garden sites eliminates important early beetle food sources. Delayed planting favors the development of host plants over the establishment of flea beetles.

A number of insecticides (granular and foliar) are available to control adult flea beetles. For recommended chemicals and rates of application, consult the North Carolina Agricultural Chemicals Manual.

Figure 7A. Eggplant flea beetle.

Illustration by USDA.

Side view of slender, curved, pale grub with small, dark head, three small legs on thorax, and proleg at rear. Short bristles all over body.

Figure 7B. A typical flea beetle larva.

Illustration by NC Agricultural Experiment Station.

Oval pupa with appressed face, antennae, first two pairs of legs, and wing pads. Hind legs under wing pads. Two spines at tip of abdomen and some short hairs.

Figure 7C. A typical flea beetle pupa.

Illustration by USDA.

Single eggplant leaf, slightly curled inward lengthwise. Dotted by many tiny, glossy-black flea-like beetles. Surface is heavily pitted with small, pale spots.

Figure 8. Eggplant flea beetles and damage to eggplant foliage.

Photo by David Cappaert, Bugwood.org.