PPRI GOS 01
Sequencing and sequence analysis of divergent molecular variants of GVA associated with Shiraz disease
Goszczynski, D E
ARC Plant Protection Research Institute
Jooste, A E C
Shiraz disease is highly destructive in Shiraz, Merlot, Gamay, Malbec and Viognier cultivars in South Africa. Infected plants never recover, and die within 3-5 years. First symptoms of the disease are visible in new growth. Canes show overgrown phloem and weakly developed xylem tissue. They do not mature. Shiraz disease affected plants shed leaves much later than plants that are free of this disease.
Results indicate that GVA, a Vitivirus, is associated with Shiraz disease. The results strongly suggest that only virus variants of one molecular group are able to induce the disease. The virus is transmitted by the mealybug Planococcus ficus, a pest which is common in local vineyards. It poses a serious threat to Shiraz disease susceptible cultivars in South Africa. To understand the virus better, detailed molecular analysis of various variants of different molecular groups, mainly those associated with Shiraz disease, was initiated.
Goszczynski, D E, Du Preez, J, Burger, J. 2007. Molecular divergence of grapevine virus A (GVA) variants associated with Shiraz disease in South Africa. Presentation at the 7th Grapevine Virus Workshop. 2 May, ACR Infruitec-Nietvoorbij, Stellenbosch, South Africa.
Goszczynski, D E, Du Preez, J, Burger, J T. 2008. Molecular divergence of grapevine virus A variants associated with Shiraz disease in South Africa, Virus Research, v. 138 (p. 105-110)