Disease Note.

First Report of Sweetpotato Virus Disease-Associated Closterovirus in Brazil. G. Pio-Ribeiro, IPA, Bongi, 50761-000, Recife, PE, Brazil. S. Winter and R. I. Hamilton, Agriculture Canada Research Station, Vancouver, Canada V6T 1X2; and F. M. de Assis Filho and C. D. da Paz, UFRPE, Dois Iramaos, 52171-900, Recife, PE, Brazil. Plant Dis. 78:1122. Accepted for publication 10 June 1994. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-1122B.

In 1993, plants of Ipomoea batatas (L.) Lam. (sweetpotato) in 2/48 accessions of the germ plasm collection at the Universidade Federal Rural de Pernambuco (UFRPE) in northeast Brazil expressed symptoms resembling those of sweetpotato virus disease (SPVD), first reported in Nigeria in 1976 (1). Ipomoea setosa Ker., a standard indicator host for sweetpotato viruses, showed feathered leaves and severe stunting typical of SPVD when grafted with scions from these plants. In grafted I. setosa and in diseased sweetpotato, sweetpotato feathery mottle potyvirus (SPFMV) was detected by ELISA. In addition, sweetpotato virus disease-associated closterovirus (SPVD-AC) (2), was detected by dot-blot and Northern-blot hybridization using RNA probes complementary to RNA of the Nigerian isolate. The dsRNA patterns from SPVD-infected Brazilian and Nigerian sweetpotato were similar. One of the SPVD-infected accessions (Pedra 2, Batata Recife) was obtained from Pedra, PE. The other (UFRPE 1-88) was obtained from the cultivar Julian, imported from the United States before 1971, by selecting a plant regenerated from seed produced in Recife. The epidemiological significance of SPVD-AC for sweetpotato production in Brazil is being assessed because UFRPE has been the source of germ plasm for distribution to sweetpotato growers. Part of this research was funded by the International Board for Plant Genetic Resources (IBPGR), Rome.