Bacterial communities in the rhizosphere of biofortified BRS pontal and conventional carioca bean (Phaseolus vulgaris) plants.

The current knowledge of bean plants microbiome is far from being complete. Unraveling the complexity of the bacterial communities within common bean cultivars that may significantly contribute to plant health, growth and protection against soil pathogens, represents a major challenge. In this study, the richness and composition of the bacterial communities from bean plant rhizospheres and control bulk soils were analyzed by high-throughput sequencing and comparative analyses. From the classified sequences, Proteobacteria represented the most abundant phylum (42-66%), followed by Acidobacteria (12-36%) and Actinobacteria (11-18%), Bacterial community structures were different between bulk soil and rhizosphere samples. Comparing the bean cultivars, the biofortified cultivar presented high number of sequences affiliated to the genera Burkholderia and Rhodanobacter. Interestingly, despite the presence of stable and persistent core bacterial taxa associated with the common bean varieties, our analysis suggested that the biofortified common bean cultivar could select and maintain differential abundances of microbial groups in the rhizosphere environment.