Abstract:

To investigate the variations in fungal community diversity in the rhizosphere of Panax notoginseng across different soil types in Wenshan region and elucidate the characteristics of fungal communities associated with P. notoginseng, four representative soils from P. notoginseng planting areas, including Pingba Township of Wenshan City (WA), Weimo Township of Yanshan County (WB), Lianhuatang Township of Xichou County (WC), and Jiahanqing Township of Maguan County (WD), were selected as research subjects. High-throughput sequencing technology was employed to analyze the differences and features of fungal community structure among different soil types. The results revealed that at the phylum level, Ascomycota (65.76%-88.60%), Mortierellomycota (2.75%-26.20%), and Basidiomycota (2.82%-5.44%) were identified as the top three dominant phylum, respectively. The diversity indices of treatment WB including Chao1, Ace and Shannon were significantly higher than other treatments, with respective values of 327.47, 328.35 and 3.22. PCA analysis demonstrated significant dissimilarities in fungal community structures among each treatment’s soil samples with low similarity (Adonis， R²=0.533, P=0.001). LefSe enrichment analysis indicated notable disparities in enriched fungal taxa among treatments. Treatment WA exhibited significant enrichment of beneficial fungi such as Mortierella and Penicillium within Mortierellomycetes class except for unknown classification. Treatment WB displayed substantial enrichment of Chaetothyriales and Eurotiomycetes. Cucurbitariaceae and Sordaria were significantly enriched within treatment WC. In the treatment WD, Laboulbeniomycetes and Saccharomycetes exhibited significant enrichment. Furthermore, a significant positive correlation was observed between ginsenoside Rd and the pathogenic fungus Fusarium, while Plectosphaerella displayed a significant negative correlation with R1, Rb1, and Rd. Ginsenoside Re demonstrated a noteworthy positive correlation with the pathogenic fungus Ilyonectria; however, it exhibited a substantial positive correlation with the potential beneficial fungus Chaetomium. In terms of community correlation analysis, Fusarium exhibited an inverse relationship with Sclerotinia and Conlarium. These fungi could potentially serve as valuable fungal resources that antagonize root rot pathogens in P. notoginseng plants and possess functions against pathogenic fungi. This study provides novel insights for exploring biocontrol agents in P. notoginseng cultivation areas in Wenshan Prefecture for soil improvement and promoting high-quality production of P. notoginseng.

Key words: Panax notoginseng, soil types, rhizosphere, fungal community, diversity, fungal community diversity, high-throughput sequencing, biological control, ginsenosides