Department of Molecular and Cellular Biology, the University of Guelph, Guelph, ON N1G 2W1, Canada.
Department of Genetics, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
Viruses. 2022 Dec 21;15(1):23. doi: 10.3390/v15010023.
Syrah decline, first identified in Southern France in the 1990s, has become a major concern in the global grape and wine industry. This disease mainly affects Syrah (Shiraz) grapevines. Characteristic symptoms include the bright and uniform reddening of leaves throughout the canopy in late summer or early fall; the appearance of abnormalities on the trunk, mainly at the graft union (swelling, pits, grooves, and necrosis); and a reduction in vine vigor, yield and berry quality. Diseased vines may die a few years after disease onset. Damages to the vine are even more pronounced in cool climate regions such as Ontario (Canada), where the affected vines are subjected to very cold and prolonged winters, leading to large numbers of vine deaths. Despite the extensive efforts of the global grape research community over the past few decades, the etiology of this disease remains unclear. In this study, we conducted extensive analyses of viruses in declining Syrah vines identified in commercial vineyards in the Niagara region (Ontario, Canada) through high-throughput sequencing, PCR, RT-PCR and the profiling of genetic variants of select viruses. Multiple viruses and viral strains, as well as three viroids, were identified. However, an unequivocal causal relationship cannot be established between Syrah decline and any of these viruses, although the possibility that certain virus or genetic variants, or both in combination, may contribute to the disease cannot be excluded. Gleaning all information that is available to date, we feel that the traditional approach and an insistence on finding a single cause for such a complex disorder in a woody perennial fruit crop involving grafting will prove to be futile. We hope that this study offers new conceptual perspectives on the etiology of this economically important but enigmatic disease complex that affects the global grape and wine industry.
西拉衰退病，于 20 世纪 90 年代在法国南部首次被发现，现已成为全球葡萄和葡萄酒产业的主要关注点。该病主要影响西拉（设拉子）葡萄植株。其特征性症状包括：夏末或初秋整个树冠叶片均匀明亮地变红；树干出现异常，主要在嫁接部位（肿胀、凹陷、凹槽和坏死）；葡萄藤活力、产量和浆果质量下降。发病后几年，患病葡萄藤可能死亡。在安大略省（加拿大）等气候凉爽的地区，葡萄藤受到极冷和漫长冬季的影响，受损更为严重，导致大量葡萄藤死亡。尽管过去几十年全球葡萄研究界做出了广泛努力，但该病的病因仍不清楚。在这项研究中，我们通过高通量测序、PCR、RT-PCR 和选择病毒遗传变异的分析，对尼亚加拉地区（加拿大安大略省）商业葡萄园中鉴定出的衰退西拉葡萄藤中的病毒进行了广泛分析。鉴定出多种病毒和病毒株，以及三种类病毒。然而，不能明确西拉衰退病与任何这些病毒之间存在因果关系，尽管不能排除某些病毒或遗传变异体，或两者结合可能导致该病的可能性。鉴于迄今为止获得的所有信息，我们认为，对于涉及嫁接的这种复杂木质多年生水果作物的单一疾病，采用传统方法并坚持寻找单一病因，将证明是徒劳的。我们希望本研究为这一影响全球葡萄和葡萄酒产业的具有经济重要性但神秘莫测的疾病复合体的病因提供新的概念视角。
