: 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.
Song-Zi Li, Ye Liu, Yuqing Zheng et al.· Phyton· 0 citations
Background: This study aimed to investigate the molecular mechanisms underlying the response of Codonopsis pilosula roots to Fusarium oxysporum infection, which causes root rot and significant economic losses, and to provide a theoretical basis for breeding resistant varieties and developing effective control strategies. Methods: Root samples of C. pilosula were inoculated with F. oxysporum and harvested across five distinct intervals (0, 6, 24, 72, and 120 h after inoculation). Transcriptome sequencing was performed on 15 samples, generating 171.65 GB of clean data. De novo assembly was used to construct unigenes, followed by functional annotation and differential expression analysis. In addition, CpMAPK9 was transiently overexpressed in C. pilosula leaves to evaluate its role in jasmonic acid (JA) biosynthesis and disease resistance. Results: A total of 94,896 unigenes were obtained. Functional analysis showed that genes involved in hormone signal transduction, the MAPK signaling pathway, and plant–pathogen interactions were consistently activated in response to infection. Among the MAPK gene family, CpMAPK9 showed significant expression changes. Transient overexpression of CpMAPK9 significantly increased JA accumulation, indicating that CpMAPK9 positively regulates JA biosynthesis and may enhance resistance to root rot. Conclusions: In conclusion, our findings indicate that CpMAPK9 actively modulates JA-mediated defense pathways in C. pilosula during F. oxysporum invasion. Our findings shed light on the intricate molecular networks that drive disease defense, offering valuable theoretical insights to guide subsequent crop improvement initiatives.