The Fungal Microbiome in the Vineyard Ecosystem Plays a Key Role in Shaping the Regional Characteristics of Wine

The regional characteristics of wine are shaped by the synergistic effects of vineyard climate conditions, soil microbial microorganisms, soil properties, and grape must microorganisms; however, their role in shaping regional wine quality is still poorly understood. In this study, soil, grape must, and fermentation samples were collected from Cabernet Sauvignon vineyards in five regions of China. High-throughput sequencing technology was used to analyze the microbiota, and Headspace-Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry (HS-SPME-GC-MS) was used to determine the wine metabolite profile. The results showed that the wine metabolite profiles from different vineyards were significantly different and could be distinguished by their volatile compounds, with each vineyard possessing unique characteristic metabolites. The geographical origin of vineyards significantly influenced the microbial diversity of both soil and winery environments. Although the microbiota changed during fermentation, regional microbial signatures were preserved at the end of fermentation. The random forest model indicated that fungal diversity and weather are key predictors influencing wine regionality, with fungal diversity in grape must having the greatest impact. Partial least squares path modeling further revealed that fungal diversity in grape must had the most significant impact on wine metabolite profiles, followed by weather and then soil fungal diversity. In contrast, soil properties and soil bacterial diversity had weaker effects on these profiles and were significantly influenced by the weather. Overall, this study provides a novel perspective for understanding the mechanisms underlying wine regionality and clarifies the key role of microorganisms, particularly fungal communities, in shaping wine regionality.