EXPERIMENTS ON THE TRANSMISSIBILITY OF SHARKA VIRUS BY APHIDS
In a further set of experiments we compared the transmission of two sources of the necrotic strain (source A and B) and one source of the yellow strain of the sharka virus. Myzus persicae was used as vector. The results showed that the three sources examined distinguish themselves from each other in their transmissibility. The yellow strain was transmissible from N. clevelandii to N. clevelandii and to peach. Source B of the necrotic strain was readily transmitted from N. clevelandii to N. clevelandii, but peach seedlings could not be infected. Finally, source A of the necrotic strain was not transmissible by aphids, neither to N. clevelandii nor to peach.