Species of Botryosphaeriaceae involved in grapevine dieback in China

Botryosphaeria dieback is a serious disease problem for table and grape wine production worldwide. The disease however, has been less well-studied in China. In this study, we surveyed Botryosphaeria dieback in 72 vineyards of 20 grape-growing regions in China and found that Botryosphaeria dieback occurs in 18 out of 20 provinces. Morphological and multi-gene phylogenetic analyses confirmed that Botryosphaeria dothidea, Diplodia seriata, Lasiodiplodia theobromae and Neofusicoccum parvum are associated with different grapevine dieback symptoms. This study also revealed considerable differences in the geographical distribution of Botryosphaeriaceae species in China with Lasiodiplodia theobromae and Neofusicoccum parvum occurring only in subtropical monsoon climate regions, Diplodia seriata occurring only in temperate monsoon climate regions, and Botryosphaeria dothidea occurring in both temperate and subtropical monsoon climate regions. Analysis of 26 isolates showed that there is little genetic variation within species. Koch's postulates were satisfied for all species, and pathogenicity testing showed that among the 25 major cultivars growing in China, none was resistant to the four taxa. The current paper represents the first detailed report on Botryosphaeria dieback of grapevines in China.