Bacterial endophytic communities in the grapevine depend on pest management

Microbial plant endophytes are receiving ever-increasing attention as a result of compelling evidence regarding functionalinteraction with the host plant. Microbial communities in plants were recently reported to be influenced by numerousenvironmental and anthropogenic factors, including soil and pest management. In this study we used automated ribosomalintergenic spacer analysis (ARISA) fingerprinting and pyrosequencing of 16S rDNA to assess the effect of organic productionand integrated pest management (IPM) on bacterial endophytic communities in two widespread grapevines cultivars(Merlot and Chardonnay). High levels of the dominantRalstonia,BurkholderiaandPseudomonasgenera were detected in allthe samples We found differences in the composition of endophytic communities in grapevines cultivated using organicproduction and IPM. Operational taxonomic units (OTUs) assigned to theMesorhizobium,CaulobacterandStaphylococcusgenera were relatively more abundant in plants from organic vineyards, whileRalstonia,BurkholderiaandStenotrophomonaswere more abundant in grapevines from IPM vineyards. Minor differences in bacterial endophytic communities were alsofound in the grapevines of the two cultivars.