Inferences from inventories of microbes in ecological vineyard settings

The effect of degraded soil conditions on microbial communities associating the rhizosphere and roots of grapevines was investigated within the frame of project CORE Organic Plus ReSolVe. Several relationships based on Dice cluster analyses of DGGE gel profiles suggest that fungal and bacterial communities from degraded and non-degraded areas differ. Results also suggest that composted organic amendments had an effect on community structures. However, the comparison of diversity indexes did not show differences between degraded and non-degraded plots. They suggested rich and even diversity of bacteria and fungi in any of the tested samples. Culture dependent analysis emphasized that a high diversity of Streptomyces spp. associates grapevine roots in degraded and non-degraded areas. Streptomyces species, best known for their potential to produce antibiotics, are increasingly depicted as beneficial plant associated bacteria.