The diversity pattern of soil bacteria in the rhizosphere of different plants in mountain ecosystems

Research on the composition and diversity of rhizosphere microbial communities of different plant species can help to identify important microbial functional groups or functional potentials, which is of great significance for vegetation restoration and ecological reconstruction. To provide scientific basis for the management of mountain ecosystem, the diversity pattern of rhizosphere bacterial community was investigated using 16 S rRNA high-throughput sequencing method among different host plants (Cirsium japonicum, Artemisia annua, Descurainia sophia, Lepidium apetalum, Phlomis umbrosa, and Carum carvi) in Tomur Peak National Nature Reserve, China. The results showed that the richness and diversity of rhizosphere bacteria were highest in Descurainia sophia, and lowest in Lepidium apetalum. Pseudomonadota, Acidobacteriota, and Actinomycetota were the common dominant phyla, and Sphingomonas was the predominant genus. Furthermore, there were some specific genera in different plants. The relative abundance of non-dominant genera varied among the plant species. Canonical correspondence analysis indicated that available potassium (AK), total phosphorus (TP), total potassium (TK), and soil organic matter (SOM) were the main drivers of bacterial community structure. Based on PICRUSt functional prediction, the bacterial communities in all samples encompass six primary metabolic pathways and 47 secondary metabolic pathways. The major secondary metabolic pathways (with a relative abundance of functional gene sequences > 3%) include 15 categories. Co-occurrence network analysis revealed differences in bacterial composition and interactions among different modules, with rhizosphere microorganisms of different plants exhibiting distinct functional advantages. This study elucidates the distribution patterns of rhizosphere microbial community diversity in mountain ecosystems, which provides theoretical guidance for the ecological protection of mountain soil based on the microbiome.