Peanut (Arachis hypogaea L.) pod and rhizosphere harbored different bacterial communities

Abstract

Peanut is an important oil crop in the world. A full understanding of the rhizosphere and peanut pods bacterial communities and function are still lacking. In this study, we found the bacterial collections isolated from the peanut pods promoted the germination of peanut seeds. The bacteria community around rhizosphere and pods of peanut were further analyzed by 16S rRNA amplicon sequencing. The bacteria community around the pods was highly diversified and significantly different from that of the rhizosphere. Almost all the phyla and 174 of the genera contributed to the difference. Among the top four phyla, the abundance of Acidobacteria was higher in the geocarposphere, while the abundance of Proteobacteria and Actinobacteria were higher in the rhizosphere. The top two genera, Dyella and Burkholderia, were more abundant in the rhizosphere than in the geocarposphere. The core microbiome around pods consisted of more operational taxonomic units (OTUs) than the rhizosphere microbiome, and harbored a more complex co-occurrence network. In order to obtain functional microorganisms, 7 OTUs with greater degree centrality were selected through the co-occurrence network. An Arthrobacter isolate was found to significantly increase the seed germination rates. The differences in the bacterial community between the pods and rhizosphere of peanut provided an efficient method to exploring beneficial bacterial resources for yield enhancement.