While total bacteria and Betaproteobacteria were correlated with the presence of thymol in the leaves, the Alphaproteobacteria community was correlated with the presence of both thymol and carvacrol (more specifically in the genotype

LSID104 where carvacrol is the main essential oil component). Because Rhizobium was the predominant genus detected within the Alphaproteobacteria community, we may BTSA1 ic50 assume that it can withstand the presence of the volatile components of the essential oil. The same postulation can be made for the genera Comamonas and Acidovorax because they Napabucasin nmr were only found in samples from leaves. In contrast, no specific grouping was observed when Actinobacteria were considered. Actinobacterial communities do not seem to be influenced drastically by plant location or the presence of the essential oil in the leaves of L. sidoides. It is well documented that Actinobacteria are particularly adapted to survival in harsh environments [43], which may explain why strains belonging to the genera Curtobacterium, Microbacterium, Brevibacterium and click here Corynebacterium were isolated in this study. Corynebacterium was the only actinobacterial genus found

in the leaves (genotype LSID105). When the fungal communities were evaluated, we also observed the influence of the part of the plant sampled on their structure, as previously demonstrated for bacteria. However, the DGGE profiles were more complex, and a greater diversity of genera was observed within the fungal communities. The phylum Ascomycota was prevalent among the different fungal taxa found. Similarly, Siqueira et al. [44] isolated endophytic fungi representing different species belonging to the groups Ascomycota, Coelomycetes and Hyphomycetes from L. sidoides Cham. In Hevea

brasiliensis (rubber tree), Gazis and Chaverri [45] observed fungal communities present in the leaves that were different many from those isolated from the stem. Ascomycota was also the prevalent fungal group found. Based on PCA, fungal communities were to some extent correlated with the presence of thymol in the leaves. Conclusion On the basis of the data from bacterial and fungal communities found in the leaves and stems of different genotypes of L. sidoides, we believe that both communities are selected by the conditions found in the interior of the plant. Thus, the presence of an essential oil with antimicrobial properties in the leaves certainly represents harsh survival conditions for the endophytic microorganisms. To understand how the microbial community associated with L. sidoides contributes to the physiology of the plant is the next step to be achieved. Acknowledgements This study was supported by grants from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ). References 1.