MULTIPLE PARASITISM OF THE PEA APHID: STAGE OF DEVELOPMENT OF PARASITE DETERMINES SURVIVAL OFAPHIDIUS SMITHIANDPRAON PEQUODORUM(HYMENOPTERA: APHIDIIDAE)

Abstract

Chow and Mackauer (1984) recently reported on inter- and intraspecific larval competition betweenAphidius smithiSharma & Subba Rao andPraon pequodorumViereck (Hymenoptera: Aphidiidae), when both were parasitizing the pea aphid,Acyrthosiphon pisum(Harris) (Homoptera: Aphididae). In interspecific competition, a 1st-instarPraonlarva usually eliminated, by physical combat, anAphidiuslarva that was up to 48 h older. However, circumstantial evidence suggested that once anAphidiuslarva had reached an advanced stage of the final (4th) instar, it was able to complete development and pupate, even in the presence of a youngerPraoncompetitor.