A viroid (GV) was isolated from grapevines recently introduced into Japan from France, West Germany, Austria, Hungary and U.S.A., as well as from those cultivated in Japan. It was detected in 28 out of 32 (88%) grapevines tested. The isolates of GV had similar host ranges and induced symptoms in cucumber plants identical to those induced by hop stunt viroid (HSV).

The result indicates that GV is a grapevine isolate of HSV and suggests that grapevines were the source of hop stunt disease in Japan.

Sano et al. (1986) A Viroid Resembling Hop Stunt Viroid in Grapevines from Europe, the United States and Japan.- J Gen Virol August 1986 vol. 67 no. 8 1673-1678

doi: 10.1099/0022-1317-67-8-1673