Microbial map of the world's vineyards:Applying the concept of microbial terroir on a global scale

The specific microbial biodiversity linked to a particular vineyard location is reported to be a crucial aspect, in conjunction with edaphic, climatic and human factors, in the concept of wine terroir. These biogeographical patterns are known as microbial terroirs. This study applied an HTS amplicon library approach in order to conduct a global survey of vineyards soil microbial communities. In all, soil samples from 200 vineyards on four continents were analysed in an attempt to establish the basis for the development of a vineyard soil microbiome map to represent microbial wine terroirs on a global scale. This study established links between vineyard locations and microbial biodiversity on different scales: between continents and countries, and between different wine regions within the same country. Geography had a strong effect on the composition of microbial communities on a global scale, which was also maintained on a country scale. Furthermore, a predictive model was developed, based on random forest analyses, to discriminate between microbial patterns in order to identify the geographical source of the samples with reasonable precision. Finally this study is the first to describe the microbial community of new and northern wine-producing regions, such as Denmark, that could be of great interest for viticulture adaptation in a context of climate change.