Role of Host Plant in Production of Winged Forms by a Green Strain of Pea Aphid Acyrthosiphon pisum Harris

Abstract

THE importance of tactile contacts between aphids, or the effet de groupe as first described by Bonnemaison¹, has been demonstrated in several species of aphids. Lees² has reviewed work in this field, and has evaluated the claims of those who have invoked “nutrition” as the important factor in the production of these forms, rather than any crowding factor. He concluded: “Unequivocal evidence that starvation or malnutrition, or specific changes in the quality of the plant sap, can cause isolated aphids to become alatae or alata-producers is still lacking”.