First report of Grapevine Syrah virus 1 infecting grapevines in Korea

Authors: CHO, IN-SOOK - Rural Development Administration - Korea; YANG, CHANG YOUL - Rural Development Administration - Korea; KWON, SUN-JUNG - Rural Development Administration - Korea; YOON, JU-YEON - Rural Development Administration - Korea; KIM, DAE HYUN - Rural Development Administration - Korea; CHOI, GUG-SEOUN - Rural Development Administration - Korea; Hammond, John; MOON, JAE-SUN - Korea Research Institute Of Bioscience And Biotechnology; LIM, HYOUN-SUB - Chungnam National University

Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2019
Publication Date: 7/17/2019
Citation: Cho, I., Yang, C., Kwon, S., Yoon, J., Kim, D., Choi, G., Hammond, J., Moon, J., Lim, H. 2019. First report of Grapevine Syrah virus 1 infecting grapevines in Korea. Plant Disease. 103(11):29-70. https://doi.org/10.1094/PDIS-05-19-1037-PDN.
DOI: https://doi.org/10.1094/PDIS-05-19-1037-PDN

Interpretive Summary: Virus infections cause losses of crop yield or quality. Virus infection can be especially problematic in vegetatively propagated perennial crops, as infections are passed on to plants produced from infected mother plants, and additional viruses may accumulate through mechanical or vectored transmission during the life of the crop. Even viruses that cause little obvious damage in a single infection may exacerbate symptoms and losses in a mixed infection. Scientists in Korea identified multiple viruses and viroids in a symptomatic grapevine hybrid ‘Kyoho’ showing yellow spots on the foliage, small clusters of fruit, and uneven fruit ripening. Among the seven viruses and two viroids identified, one had not previously been known to occur in Korea; this virus, Grapevine Syrah virus 1, was found to be most closely related to an isolate previously reported from Brazil. Additional grapevine cultivars were tested specifically for Grapevine Syrah virus 1, which was detected only in one plant of ‘Campbell Early’, the most widely-grown table grape variety in Korea. The infected vine showed symptoms of poor fruit set. Although Grapevine Syrah virus 1 has not been consistently associated with symptoms in other countries where it has been reported, occurrence in the most popular table grape in Korea suggests a need for additional screening of grapevine propagation stocks to select plants free of this and other viruses.

Technical Abstract: Grapevine Syrah virus-1 (GSyV-1), a member of the genus Marafivirus in the family Tymoviridae, was first reported from grapevines in the United States. Although GSyV-1 has been reported in many other countries including Chile, Italy, France, Slovakia, the Czech Republic, Brazil, Hungary, South Africa, and more recently in Turkey, Spain and China, it has not been clearly related to any disease (Caglayan et al. 2017; Ruiz-Garcia et al. 2017; Ahmed et al. 2017). In 2017, a grapevine (Vitis labrusca × V. vinifera ) cv. Kyoho showing yellow spot on leaves and uneven ripening of berries and smaller clusters on grapes were observed in Gimje, Korea. Total RNA was extracted and used for constructing a cDNA library followed by high throughput sequencing (HTS) on an Illumina HiSeq 4000 platform. Generated reads were de novo assembled into contigs and identified through BLAST analysis. From the HTS data, seven viruses and 2 viroids were identified: GSyV-1, Grapevine leafroll-associated virus 3 (GLRaV-3), Grapevine fleck virus (GFkV), Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine Pinot gris virus (GPGV), Grapevine geminivirus A (GGVA), Grapevine fabavirus (GFabV), Hop stunt viroid (HSVd) and Grapevine yellow speckle viroid 1 (GYSVd-1). Six contigs with lengths of 280 to 464bp showed identities of 93.0 to 98.2% with GSyV-1 isolates in GenBank. To confirm the presence of GSyV-1, RT-PCR was performed using virus-specific primer pairs GSyV-1 F/ GSyV-1 R (5’-TTCCAATGGCAGA-CCAAGG-3’/5’-TGTGTAGGTCGGATGACG-3’) and SY3755F/SY4677R (Glasa et al., 2015). PCR products of the expected 408 bp and 919 bp were obtained and sequenced. The sequences (GenBank accession no. LC481448, LC481449) showed 94.8 and 94.0% identity with MH isolate from Brazil (KT037017), respectively. A further 164 grapevine samples were collected from various cultivars and screened for the occurrence of GSyV-1, which was detected only in one grapevine cv. Campbell Early showing poor fruit set among these tested samples. GSyV-1 occurred at low frequency, and was not clearly associated with symptoms on the infected grapevines. To our knowledge, this is the first report of GSyV-1 infecting grapevines in Korea.