Metagenome-Assembled Genomes from maize rhizobiome contribute to unravel key microbial taxa in the community influenced by the inoculant Azospirillum brasilense

Plants strategically recruit beneficial microbiomes throughout their developmental stages. As a result, the plant-mediated soil microbiome legacies have long-lasting major impacts on subsequent crop seasons through plant-soil feedbacks. The ecological recruitment of microbiota from crop soil upon inoculation with a plant growth-promoting bacteria (PGPB) is still understudied. The effect of plant-associated soil microbiome in the performance of the PGPB Azospirillum brasilense strain Ab-V5, a commercial inoculant for maize and other crops, has been investigated in a dilution-to-extinction gradient. Previous results revealed a weak maize growth promoting effect of Ab-V5 inoculation in natural soil, contrasting the positive effects of diluted soil and irradiated soil. Although a large amount of metagenomic sequencing studies are available, modern bioinformatic approaches are necessary to fully understand the potential of plant growth promoting bacterial communities influenced by the inoculant strain Ab-V5. The characterization of putative metabolic contributions of metagenome-assembled genomes (MAGs) are useful for this purpose. In this study, MAGs from maize rhizosphere microbiomes are dissected and their putative phenotypic and metabolic potentials are discussed.