Diversity of bacterial communities in the rhizosphere of the endangered plant, Paeonia jishanensis

Abstract

The microbial community in the rhizosphere is thought to provide plants with a second set of genomes, which plays a pivotal role in plant growth. In the present study, soil samples were collected from the rhizosphere of an endangered plant, Paeonia jishanensis. The plants were divided into three groups: well-growing plants, poor-growing plants and dead plants. Metagenomic DNA was isolated from rhizosphere soil samples of these plants and 16S rRNA genes were sequenced by the PacBio-RS II system. The results of taxonomic analysis showed that the dominant phyla were Proteobacteria, Acidobacteria, Planctomycetes, Bacteroidetes and Actinobacteria in all three sample types. Linear discriminate analysis Effect Size (LEfSe) showed that 5 species, Hirschia baltica, Arcobacter aquimarinus, Gimesia maris, Magnetococcus marinus and Pseudoxanthobactor soli, were significantly enriched in the rhizosphere of well-growing plants. Additionally, the results of PCA, MDS and clustering analysis indicated that the bacterial community in the rhizosphere of living P. jishanensis plants was similar. With the death of plants, the bacterial community changed considerably. These findings suggest that the abundance of many beneficial rhizospheric microbes declined with the death of P. jishanensis. This is a potential way to preserve endangered plants by inoculating declining species with beneficial microbes.