Corn earworms are considered as one of the most damaging pests of corn. All the larval stages of corn earworms cause serious damage to corn but their adult moths are not harmful to any plant parts of corn or any other host crops. Young larvae generally feed on corn silk but mature larvae burrow into the ear and feed on the kernels. In addition to corn, larvae of corn earworm can cause considerable damage to tomatoes.
Adults: Adult moths of corn earworm have yellowish brown forewings with a black spot at the center of each forewing. Hindwings are creamy white and blackish in color. Moths are active during night but they become inactive and hide in the vegetation during daytime.
Eggs: Newly laid eggs are pale green in color but they turn yellowish gray in color just before hatching.
Larvae/Caterpillars: Larvae of corn earworms are variable in color but their head capsule is orange to brown in color. Larvae of corn earworms have dark stripes on the lateral sites.
Corn earworms overwinter as pupae in the soil and emerge as moths from the pupae in the spring. After mating, female moths lay eggs singly in the corn silk or on the leaf hairs. Eggs hatch within a week into small larvae that start feeding on the silk and then move down the ear where they feed on the kernel. These larvae develop through 6 stages and become mature. Matured larvae then fall off the plant and pupate in the soil. Moths will emerge from pupae and life cycle will continue. Under favourable conditions, corn earworms can complete two generations in a year.