Metagenomics analysis of soil prokaryote community composition and diversity at 22 Barossa Valley vineyard sites

Abstract

Soil is one of the influential factors that defining a wine’s terroir or the uniqueness of a wine produced by vines grown in specific conditions and also by different winery process (e.g.,oak process).Recentdata shows that the diversity, distribution and composition of soil microbial communities may play important roles in determining wine quality and indirectly affect its economic value. Here, we evaluated the impact of environmental factors on microbial composition and diversity of 22 Barossa Valley vineyard sites using metagenomics tools based on the 16S rRNA gene hypervariable region 4.In this study, we report that environmental heterogeneity (rainfall, temperature, soil moisture, soil P content) in different regions caused morephylogeneticdissimilarity than geographic distance. Eden Valley and Western Ridge showed lower diversity and a higher ratio of dominant taxa, and this was correlated with a correlatedwith higher rainfall. The coldest region, Eden Valley, had the lowest diversity. Combined withfunctional analysis of metagenomicsdata, soil microbial community composition and diversity has the potential to be useful biological indicators of grape berry and wine characteristics. Importantly, these features significantly associated withchanges in the microbial communities, highlighting the influence of microbiome on the grape plants. Our results suggest that environmental factors affect wine terroir and this may be mediated by changes in microbial structure, thus providing a basis understanding of the mechanistic interactions between plants and growing conditions.