Cross study reveals ubiquitous bacterial taxa across legume rhizospheres

Abstract

The soil adjacent to roots, known as the rhizosphere, harbors a microbial community whose structure differs from that of the surrounding soil. Rhizosphere inhabitants play a significant role in plant health and growth. Identifying the most important players can impact and guide future research in plant-microbial interactions. In this paper, we analyzed and compared the rhizospheric communities of eight economically relevant legume species. We collected publicly available sequencing data and processed them de novo from raw data to the taxonomic assignments of the sequences. The hypothesis of our work was the existence of core bacterial taxa present in most rhizospheres, despite differences in different plant rhizosphere communities. Desmodium and Mimosa rhizospheres harbored high-diversity communities, whereas Lotus and Trifolium rhizospheres harbored low-diversity communities. Although communities from some studies were located outside the main cluster in the ordination plot, this separation was not statistically significant, indicating that the community structure of the different rhizospheres is similar. The most ubiquitous bacterial genera found in the rhizospheres were Mycobacterium , Pseudomonas , Devosia , and Streptomyces . The ubiquity of these bacteria in the rhizosphere of legumes highlights their ability to colonize it and the relevance of this lifestyle to the ecology of these microorganisms.