Bacterial Community Structure Responds to Soil Management in the Rhizosphere of Vine Grape Vineyards

Simple Summary Viticulture is one of the most resource-demanding agricultural sectors worldwide. Therefore, if we would like to find a way to make it more sustainable, we need to understand how cultivation methods affect the interactions between vine grape and its environment. However, very little is known about what bacteria live in the root system of grapes. Furthermore, we have even less knowledge about how the microorganisms' composition might be changed due to various tillage methods and soil disturbances. This study examined and compared the soil-bacterial microbial composition of three experimental plots using laboratory techniques and up-to-date molecular methods. We investigated soil microbial communities' composition and some cultivation practices' effects. Our results show that intensive tillage significantly and negatively affected soil bacterial community structure and diversity.Abstract The microbial communities of the rhizospheres of vineyards have been subject to a considerable body of research, but it is still unclear how the applied soil cultivation methods are able to change the structure, composition, and level of diversity of their communities. Rhizosphere samples were collected from three neighbouring vineyards with the same time of planting and planting material (rootstock: Teleki 5C; Vitis vinifera: M & uuml;ller Thurgau). Our objective was to examine the diversity occurring in bacterial community structures in vineyards that differ only in the methods of tillage procedure applied, namely intensive (INT), extensive (EXT), and abandoned (AB). For that we took samples from two depths (10-30 cm (shallow = S) and 30-50 cm (deep = D) of the grape rhizosphere in each vineyard and the laboratory and immediately prepared the slices of the roots for DNA-based analysis of the bacterial communities. Bacterial community structure was assessed by means of PCR-DGGE analysis carried out on the v3 region of 16S rRNA gene. Based on the band composition of the DGGE profiles thus obtained, the diversity of the microbial communities was evaluated and determined by the Shannon-Weaver index (H '). Between the AB and EXT vineyards at the S depth, the similarity of the community structure was 55%; however, the similarity of the D samples was more than 80%, while the difference between the INT samples and the other two was also higher than 80%. Based on our results, we can conclude that intensive cultivation strongly affects the structure and diversity of the bacterial community.