Zonation of the Vitis vinifera microbiome in Vino Nobile di Montepulciano PDO production area. null

Factors that relate wine organoleptic properties to the site of origin are embedded within the concept of terroir, which has gained outstanding importance in wine-producing countries. The microbial dimension of the terroir is now considered to be of paramount importance for final wine quality, as microbiomes are involved in plant biofertilization, stress tolerance and pathogen suppression. In particular, microbial terroir can act as a biological signature at large scale, but we still lack data for local contexts, preventing a finer characterization, exploitation, and safeguard of the regional microbial diversity associated with vineyards. Here, we define the microbial terroir of vineyards scattered across the 12 sub-areas (Additional Geographic Units -AGUs) of the “Consorzio del Vino Nobile di Montepulciano DOCG" PDO area (Italy), a world-renowned wine-producing region. To this end, rhizospheres of Vitis vinifera cultivar Sangiovese and soil samples were collected across the entire viticultural season 2022 and analyzed through an integrated metabarcoding/shotgun metagenomic approach, targeting both bacteria and fungi. While highlighting a peculiar taxonomic configuration of the Vino Nobile di Montepulciano terroir compared to other Italian and worldwide vineyards, our data show that microbiomes are “AGU-specific” in terms of taxonomic abundances and plant growth-promoting functions. The reconstructed metagenome-assembled genomes confirmed a high potential for plant growth promotion, with differences related to the AGU, considering a set of genes associated with plant well-being. In addition to enriching our understanding on the importance of microbial terroirs as biodiversity treasures with a key role in shaping wine characteristics and wine relationship with geography, this study may provide further economic incentives for agricultural and oenological practices that preserve the regional microbial terroir and biodiversity. This work was carried out in the context of the “Controlling Microbiomes Circulations for Better Food Systems” (CIRCLES) project, which was funded by the European Union's Horizon 2020 research and innovation program under grant agreement no. 818290.