Diversity of Yeast and Drosophila Species Associated with Grape Sour Rot in China

Sour rot is a complex disease of grapes, primarily caused by the synergistic effects of yeast and Drosophila species, leading to fruit decay, poor quality, and significant economic losses. The lack of information on species distribution and diversity of these organisms in China limits the efficacy of control strategies. In this study, we sequenced the 26S rRNA D1/D2 region in yeasts and the COI region in Drosophila. Nine yeast genera were identified. Hanseniaspora spp. (45.76% of total) were the most abundant, followed by Starmerella spp. (23.62%) and Saccharomyces spp. (17.34%). At the species level, 14 yeast species were identified. Starmerella bacillaris (23.62%), Saccharomyces cerevisiae (17.34%), H. opuntiae (17.34%), and H. uvarum (15.13%) predominated. Of the five species of Drosophila present, Drosophila melanogaster (63.16%) was the dominant species. This study is the first to characterize the diversity of yeasts and Drosophila across major grape-producing regions in China. The findings provide a scientific foundation for elucidating the key drivers of sour rot and designing targeted control strategies.