First report of Grapevine syrah virus-1 in Grapevines in China.
In 2017, a sample from cultivar SO4 grapevine rootstock (Vitis berlandieri × Vitis riparia) exhibiting chlorotic mottling and deformation was collected in Liaoning province in China. Results of RNA sequencing and BLAST analysis revealed four viruses and one viroid: Grapevine Syrah virus-1 (GSyV-1), Grapevine leafroll-associated virus 3, Grapevine virus A, Grapevine virus and Hop stunt viroid. Fifty-two contigs with lengths of 34 to 257 bp (53% coverage) showed 90.48 to 96.28% nucleotide (nt) identity with the genome sequence of a USA isolate of GSyV-1 (FJ436028). To further confirm the infection by GSyV-1, PCR assay and sequence comparisons were performed. To evaluate the incidence of GSyV-1 in China, 90 samples of different grapevine cultivars were collected from 10 different provinces and regions and were tested by reverse transcription PCR. The results showed that 4.4% (4 of 90) of the samples tested positive for GSyV-1. GSyV-1 was found in wine grape cultivars Cabernet Gernischt (2), Vidal blanc (1), and Marselan (1). This is thought to be the first report of GSyV-1 in China.