General Information

Common name: Corn earworm
Scientific names: Helicoverpa/Heliothis zea, H. armigera
Lepidoptera:Noctuidae

Synonyms: Tomato fruitworm, Sorghum headworm, Cotton bollworm

Host plants

Corn, sorghum, soybean, peanut, tobacco, cotton, cowpea, tomato, okra, pechay, radish, lettuce, and beans

Distribution

Helicoverpa/Heliothis zea is found in Canada, South America, and USA while H. armigera is found in Asia

Damage

Larvae feed on leaves, tassels, whorl, silks, and within ears. When larvae feed on corn silks, they clipped these off prior to feeding on the corn ears. The ears are the preferred sites for corn earworm attack. Ear damage is characterized by extensive excrement at the ear tip. They remain feeding in the tip areas until they leave to pupate in the soil.

Description

Eggs are pinhead-sized and yellow-green in color. These are found singly laid on the silk and occasionally on the husks of the corn ear. Hatching occurs within about 2-5 days.

Larvae vary in color from bright green, pink, brown, to black, with lighter undersides. Alternating light and dark bands run lengthwise along their bodies, the heads are yellow and the legs are almost black. Mature larvae vary in length about 3-5 cm. They drop to the ground to burrow into the soil to pupate. The larval stage lasts from 12-24 days.

Pupae are yellowish green and turn brown as they mature. Pupation takes place under the soil. Pupal period is 12-24 days.

An adult male is yellow-brown while a female is orange-brown in color. It has a wingspread size of about 3.8cm. Each female may deposit 200-2,000 eggs in her entire lifetime. Total development period from egg to adult is 34-45 days.