Bacterial and Fungal Communities of Table Grape Skins in Shanghai

Abstract

Grape skin serves as a reservoir for many bacteria and fungi, which can affect grape health, quality, and safety. However, grape skin microbiota and mycobiota of table grapes remain largely understudied. This study investigated bacterial and fungal communities residing on different table grapevine cultivars (‘Summer Black’ and ‘Kyoho’) as well as the impact of potential contributors thereby, via culture-dependent and culture-independent (analysis of 16S rRNA gene and internal transcribed spacer sequences) methods with different purposes. Microbiota of both grapevine cultivars were dominated by Cladosporium, Alternaria, Aspergillus, Thauera, and Pantoea. In addition, yeast strains belonging to Hanseniaspora opuntiae, Pichia terricola, Rhodotorula mucilaginosa, Candida stellimalicola, and Kodamaea ohmeri were enriched from the studied grapes, while some strains were considered as health-threatening pathogens. Differences in grapevine cultivars did not significantly affect their mycobiota and microbiota profiles. Nevertheless, their mycobiota exhibited significant variations across different grape-sampling sites in Shanghai, indicating the contribution of the grape-growing environment to grape skin mycobiota. Altogether, the current study demonstrated the contribution of the grape-growing environment to table grape skin mycobiota, and highlighted the importance of microbiota management in the production and consumption of table grapes.