A VIRUS LATENT IN TURNIPS

Abstract

Green peach aphids reared on turnip stecklings acquired a virus that was transmitted to plants of Physalis floridana Rydb. and P. pubescens L., hosts used in potato leaf roll studies. Symptoms on these hosts consisted of a yellowing of the veins of the leaves. Nicandra physalodes L., when infected, showed severe stunting and chlorosis. The virus was carried without symptoms on turnips and showed only slight stunting on several species of Brassica. It was not transmitted by mechanical inoculation and it does not appear to be similar to any of the viruses previously reported in turnips. The aphid Myzus persicae (Sulzer) acquired the virus during a seven-hour feeding period, and after a latent period of approximately 23 hr., transmitted the virus during a one-hour test-feeding period. Once infective, aphids remained so for several days.