PHLOEM NECROSIS OF POTATO TUBERS IN RELATION TO LEAF-ROLL-FREE MYZUS PERSICAE SULC.

Abstract

In experiments in which nonviruliferous colonies (25 to 50 individuals per plant) of Myzus persicae Sulc. were caged from 7 to 10 days on healthy potato vines growing under field conditions, the tubers failed to develop phloem necrosis. Under comparable conditions, the tubers from healthy plants caged with leaf-roll-infective colonies of this vector developed severe phloem necrosis. When planted, these tubers produced leaf-roll-infected plants.