Abstract
Background Ferula sinkiangensis is a desert short-lived medicinal plant, and its number is rapidly decreasing. Rhizosphere microbial community plays an important role in regulating global biogeochemical cycle, plant growth and adaptability. However, the Ferula sinkiangensis bacterial community and the processes that drive its assembly remain unclear. Results In this study, based on Illumina HiSeq high-throughput sequencing, we explored the diversity, structure and composition of Ferula sinkiangensis rhizosphere bacterial communities at different slope positions (upper, middle and bottom) and soil depths (0-10 cm, 10-25 cm, 25-40 cm) and their correlation with soil physicochemical properties. Actinobacteria (22.7%), Proteobacteria (18.6%), Acidobacteria (14.0%), Gemmatimonadetes (10.1%), Cyanobacteria (7.9%), Bacteroidetes (6.9%), Planctomycetes (3.9%), Verrucomicrobia (3.5%), Firmicutes (3.4%) and Chloroflexi (3.2%) were the dominant bacterial phyla in Ferula sinkiangensis rhizosphere soil. Variance analysis showed that the diversity and abundance of rhizosphere bacterial community in Ferula sinkiangensis were significantly different at various slope positions and soil depths. Specifically, the diversity of bacterial community was significantly higher at the top than the bottom of the slope, and the diversity and richness of bacterial community were significantly greater in the 0-10cm than the 25-40cm soil layer. Linear discriminant effect size (LEfSe) analysis showed the specific phyla and genera of bacteria affected by slope position and soil depth. For example, Planctomycetes, Sphingomonas , Rubrobacter and Adhaeribacter by slope position and significant impact on soil depth. In addition, distance-based redundancy analysis (db-RDA) and variance analysis showed that soil physicochemical factors jointly explained 29.81% of variation in Ferula sinkiangensis rhizosphere bacterial community structure. There was a significant positive correlation between available phosphorus(AP)and the diversity of Ferula sinkiangensis rhizosphere bacterial community ( p < 0.01), whereas pH largely explained the variation of Ferula sinkiangensis rhizosphere bacterial community structure (5.58%, p < 0.01), followed by altitude (5.53%), total salt (TS, 5.21%) and total phosphorus (TP, 4.90%). Conclusion Our results revealed the heterogeneity and variation trends of Ferula sinkiangensis rhizosphere bacterial community diversity and abundance on a fine spatial scale (slope position and depth) and shed new light on the interaction mechanisms between Ferula sinkiangensis rhizosphere bacterial community and soil physicochemical properties.