Occurrence of Cowpea aphid-borne mosaic virus in peanut in Brazil

Surveys of peanut crops in northeastern Brazil since 1995 showed the occurr ence of a hitherto unreported virus disease. Characteristic leaf symptoms w ere ring spots and blotches. The virus was seed transmitted in peanut (1/61 0) and cowpea (47/796). Local and systemic symptoms were observed in cowpea (cv. TVu 3433) known to be susceptible to most Cowpea aphid-borne mosaic v ines (CABMV) isolates. The virus was transmitted by aphids Toxoptera citric idus and Aphis gossypii. Using degenerate primers, the 3' terminal region o f the viral genome was cloned and sequenced. Sequence analyses of the coat protein and the 3' untranslated region indicated that the potyvirus was mos t closely related to CABMV isolates from South Africa, Zimbabwe, and the Un ited States. On the basis of genome analysis, the virus was identified as C ABMV. The natural occurrence of CABMV on peanut has so far not been reporte d. The significance of this finding especially for germ plasm exchange is d iscussed.