AVRDC International Cooperators'
Fact Sheet

Sweet Potato Insect Pests
 

Sweetpotato Leaf Roller
Brachmia convolvuli

caterpillar and damage



Damage symptoms

Leaflets may be twisted upwards or downwards to form a sheath or leaf roll. Unrolled leaves have chewed surfaces with extensive frass. In severe cases, rolled leaves are brownish and dried.


Insect characteristics

Chewing mouthparts. Caterpillars are black with distinct white marking. A well-defined white stripe runs down their backs. They are very active, Jumping and squirming at the slightest touch. Adult moths are active at night. They are dark gray or black. Their wings have two light gray patches.


Where to look

Look for rolled leaves, especially ones with obvious chewing damage, and open them. Both the larva and the reddish-brown pupa can often be found inside.


Technical information

These insects attack only sweet potato. Greenish-yellow oval eggs are flattened at each end and are laid on the undersides of leaves. The egg, larval, and pupal stages last 4, 14, and 6 days, respectively.

rolled leaf
Photo and drawing of rolled leaf
unrolled leaf
Unrolled leaf showing damage (Note: black remains are insect frass)


Control

To be added later.

 

Last updated: 2001. 
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. 

AVRDC Home | Extension Materials Home | Sweet Potato Home