Cabbage webworm

AVRDC
Crop Protection Guides

*Crucifer Insect Pests* Cabbage webworm Hellua undalis	In This Guide
	Damage symptoms
	Insect characteristics
	Where to look
	Technical information
	Control

Damage symptoms Silken webbing on the surface of the inner leaves and stalks is evident. The surrounding regions have obvious feeding holes. The area beneath the webbing contains frass and other insect remains. The growing point of seedlings may be severely defoliated. If the plant survives, several small heads may form.
		Larva feeding on tomato

Insect characteristics Chewing mouthparts. Caterpillars are pretty to look at. They are dusty yellow with broad purple stripes along the length of their bodies. Adult moths are rather nondescript and gray with small brown spots or specks.
		Larva feeding inside the fruit

Where to look

Inspect the young growing points, inner leaves, and stalks for chewing damage. If webbing is found, look underneath it for the webworm. Positive identification can only be made if the insect is found, but if webbing with dirty frass underneath is found, it is likely the damage is caused by this species.

Technical information

Female moths lay eggs on foliage near young growing points. After hatching, larvae bore into the growing point and cover themselves with a silken web, which has a exit hole in it. Larvae are voracious feeders. They pupate on shed leaves or other debris on the ground.

Control

To be added later.

Last updated: July 2000.
Information from: Field Guide: Insect Pests of Selected Vegetables in Tropical and Subtropical Asia. 1995. B.L. Parker, N.S. Talekar and M. Skinner. Publication 94-427. Pest control recommendations added.

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