First report of grapevine rupestris vein feathering virus infecting grapevines in Korea.
Grapevine rupestris vein feathering virus (GRVFV), a tentative member of the genus Marafivirus in the family Tymoviridae, was first reported from a grapevine with chlorotic discolorations of leaf veins in Greece. The virus has been reported in the USA, Canada, Uruguay, Italy, Spain, the Czech Republic, and recently in China, Switzerland, and New Zealand. In 2016, grapevine leaf samples were collected from 10 symptomatic plants showing mottling, yellowing, and malformation, as well as from five asymptomatic plants in commercial vineyards in Gimje and Sangju, Republic of Korea. From the high throughput sequencing data, contigs derived from Grapevine leafroll-associated virus 3, Grapevine fleck virus, Grapevine rupestris stem pitting-associated virus, Grapevine Pinot gris virus, Grapevine geminivirus A, Hop stunt viroid and Grapevine yellow speckle viroid 1 were identified, all of which have been previously reported in Korea. In addition, analysis of five assembled contigs ranging from 236 to 735 bp showed the presence of GRVFV; these contigs shared identities of 83.5 to 87.0% with GRVFV isolates in GenBank. The presence of GRVFV was confirmed by RT-PCR. GRVFV-infected grapevine cv. Shine Muscat did not display any characteristic symptoms. This is thought to be the first report of GRVFV infecting grapevines in Korea.