Community succession of the grapevine fungal microbiome in the annual growth cycle

Microbial ecology is an integral component of wine production. From the vineyard to the winery, microbial activity influences grapevine health and productivity, conversion of sugar to ethanol during fermentation, wine aroma production, wine quality and distinctiveness. Fungi in the vineyard ecosystem are not well described. Here, we characterised the spatial and temporal dynamics of fungal communities associated with the grapevine (grapes, flowers, leaves, and roots) and soils over an annual growth cycle in two vineyards to investigate the influences of grape habitat, plant developmental stage (flowering, fruit set, veraison, and harvest), vineyards, and climatic conditions. Fungi were influenced by both the grapevine habitat and plant development stage. The core microbiome was prioritised over space and time, and the identified core members drove seasonal community succession. The development stage of veraison, where the grapes undergo a dramatic change in metabolism and start accumulating sugar, displayed a distinct shift in fungal communities. Co-occurrence networks showed strong correlations between the plant microbiome, the soil microbiome, and weather indices. Our study describes the complex ecological dynamics that occur in microbial assemblages over a growing season and highlight the importance of core community succession in vineyards. In addition to enriching our understanding of how plants and microbes interact, these findings may provide insights to craft wine regional distinctiveness and cope with global climate change.