BIOLOGICAL FACTORS INFLUENCING THE TRANSMISSION OF POTATO LEAFROLL VIRUS BY DIFFERENT APHID SPECIES

Macrosiphum euphorbiae, collected in the field from potato plants infe cted with potato leafroll virus (PLRV), transmitted the virus to fewer potato plants in a field trial than did laboratory-reared Myzus persi cae. In the laboratory, M. persicae was the only efficient vector of P LRV from Physalis floridana seedlings, potato sprouts or excised leave s to P. floridana. Two clones of M. euphorbiae and one clone of Aulaco rthum solani transmitted PLRV from infected potato plants to Nicotiana clevelandii as efficiently as M. persicae but a clone of Aphis gossyp ii was an inefficient PLRV vector. An isolate of PLRV, which M. persic ae transmitted inefficiently from potato to N. clevelandii. was also t ransmitted inefficiently by M. euphorbiae and A. solani.