Rhizosphere Microbial Community Responses of Panax notoginseng to Contrasting Cultivation Modes

Different cultivation systems of Panax notoginseng, including wild growth, understory cultivation, and field cultivation, may create distinct rhizosphere environments. Rhizosphere soil properties and microbial communities are closely linked to the sustainability of P. notoginseng cultivation, yet comparative evidence across these cultivation systems remains limited. In this study, rhizosphere soils from two-year-old P. notoginseng grown under semi-wild, understory, and conventional field cultivation modes in Yunnan Province, China, were analyzed for soil physicochemical properties and microbial community composition using amplicon sequencing. A total of 6842 bacterial ASVs and 1014 fungal ASVs were obtained after quality control and denoising. Soil properties differed among cultivation modes, with semi-wild cultivation generally associated with higher SOC (soil organic carbon), TN (total nitrogen), and alkali-hydrolyzable nitrogen (AN), whereas the pH of it was lower than the other cultivation modes. Beta diversity analyses based on PCoA analysis and PermANOVA analysis revealed significant differences in both bacterial and fungal community composition, with fungal communities showing larger separation than bacterial communities. Semi-wild cultivation was associated with higher relative abundances of Actinobacteria and Agaricomycetes, whereas field cultivation showed a greater proportion of Proteobacteria and Sordariomycetes. Correlation analysis indicated that soil organic carbon, pH, and inorganic nitrogen were the edaphic factors most consistently associated with microbial community differentiation. These results suggest that cultivation mode was closely associated with rhizosphere soil conditions and microbial community composition in P. notoginseng, and that semi-wild cultivation may provide a more favorable rhizosphere environment for ecological stability.