Grapevine Asteroid Mosaic-Associated Virus is Resident and Prevalent in Wild, Noncultivated Grapevine of New York State

In North America, uncultivated, free-living grapevines (Vitus spp.) frequently grow alongside their cultivated counterparts, thus increasing the potential for exchange of microbiota. For this study, we used high-throughput sequencing (HTS) of small RNAs to survey for virus populations in free-living grapevines of the Finger Lakes region of New York State. Of 32 grapevines analyzed, 23 were free-living vines, while the remaining 9 were commercially grown Vitis vinifera plants from the same region. In total, 18 (78.3%) of the free-living grapevines tested were positive for grapevine asteroid mosaic-associated virus (GAMaV) infection by HTS, with detection confirmed by seminested reverse-transcription PCR and sequencing of nine isolates. Phylogenetic analyses of an ungapped alignment of the New York GAMaV sequences (length: 2,334 nucleotides) with the five known full-length or close to full-length global sequences showed that the New York isolates were broadly grouped. Of the nine cultivated plants, eight were infected with both hop stunt viroid and grapevine yellow speckle viroid 1, three were singly infected with grapevine leafroll-associated virus 3, and one harbored GAMaV. This limited survey of free-living grapevines, one of the first to use HTS, has highlighted the high incidence of a virus associated with disease in commercial V. vinifera.

Automated summary

This study surveyed virus populations in free-living grapevines in the Finger Lakes region of New York State, showing a high incidence of grapevine asteroid mosaic-associated virus (GAMaV) infection. Commercially grown Vitis vinifera plants in the same region were also found to be infected with different viruses, highlighting the potential exchange of microbiota between cultivated and uncultivated grapevines.