BIOLOGY OF SWEETPOTATO BUG, Physomerus grossipes Fabr. (Coreidae, Hemiptera)

Abstract

Eggs of the sweetpotato bug are laid in groups on the underside of leaves. The eggs have an incubation period of 15.82 days and hatchability of 86.8%. There are five nymphal instars. Total mean developmental period is 85.45 days for males and 87.69 days for females. Adult males and females are similar in general appearance except that the last abdominal segment of the male is more pointed than that of the female and the hind leg of the male has a characteristic spine. The bugs are normally most abundant from January to April and least from July to August. One parasitic species of wasp belonging to family Eulophidae (Order Hymenoptera) was observed on field-collected eggs. Plant species namely, Ipomoea aquatica, Ipomoea triloba and Bacella rubra could serve as alternate hosts ofthe insects.