DETECTION OF SWEET-POTATO VIRUS DISEASE-ASSOCIATED CLOSTEROVIRUS IN ASWEET-POTATO ACCESSION IN THE UNITED-STATES

A closterovirus (sweet potato virus disease-associated closterovirus [ SPVD-aC]) that, in association with sweet potato feathery mottle potyv irus (SPFMV), causes the Nigerian sweet potato virus disease (SPVD), w as detected in sweet potato (Ipomoea serosa) following grafting of inf ected scions of sweet potato cv. White Bunch, an accession in the USDA sweet potato repository. Confirmation of infection with SPVD-aC was b y a riboprobe hybridization assay specific for the viral RNA coupled w ith chemiluminescent detection of the bound RNA, and SPFMV was detecte d by enzyme-linked immunosorbent assay (ELISA) using a specific antise rum. This is the first report of SPVD-aC and of SPVD in sweet potato i n North America. Use of the riboprobe hybridization assay should facil itate a more rapid detection of SPVD-aC infected sweet potato and subs equent selection of virus-free germ plasm for international exchange.