Influence of Rosaceous Species and Driving Factors on Differentiation of Rhizospheric Bacteria in a Deciduous Broad-Leaved Forest

Understanding plant–microbe interactions could provide the basis for improved phytoremediation, microbial resource utilization, and secondary metabolite production. Rhizosphere bacterial communities are strongly influenced by abiotic factors such as soil nutrient availability and the composition of such communities exhibits differentiation under different host plants. In a deciduous broad-leaved forest in Anhui Province, eastern China, the rhizospheric bacteria of three different tree species of the Rosaceae family (Sorbus alnifolia, Cerasus serrulata, and Photinia beauverdiana) were studied, with the bacteria of the bulk soil as controls. Bacterial community composition was determined using the Illumina platform for high-throughput sequencing of 16S rRNA genes. The results showed that the bacterial community composition varied between rhizospheric and bulk soils, and dominant bacterial phyla as Proteobacteria, Actinobacteria, and Acidobacteria were found in both soils. Information on predicted functional genes and pathways revealed significant differences between rhizospheric and bulk soil bacteria. It provided ample evidence for the different metabolic characteristics of the rhizosphere bacterial communities of the three tree species. Electrical conductivity (22.72%), total phosphorus concentration (21.89%), and urease activity (22%) were the main drivers for changes in the composition of the rhizosphere bacterial communities from the three tree species.