呼伦贝尔草原不同地区叉分蓼可培养内生真菌群落组成与多样性OA

Polygonum divaricatum,a perennial herbaceous plant species that exhibits strong drought resistance and ecological adaptability,is commonly used as a medicinal plant in Mongolian medicine.In this study,traditional fungal isolation and culture techniques combined with ITS sequence-based molecular identification were used to reveal the composition and diversity of cultivable endophytic fungal communities associated with different plant tissues and geographic environments of P.divaricatum in the Hulun Buir Grassland.The endophytic fungal communities in the roots,stems,and leaves of P.divaricatum collected from three sampling sites(S1,S2,and S3)were investigated.Additionally,differences in the fungal community composition across plant tissues and environmental conditions were analyzed.In total,807 fungal isolates belonging to 3 phyla,12 classes,21 orders,40 families,49 genera,and 134 species were obtained from 54 plant samples.The majority of isolates were affiliated with Ascomycota,Basidiomycota,and Mucoromycota.The dominant genera varied significantly among the plant tissues,with Cephalosporium,Fusarium,and Penicillium being prevalent in roots and Alternaria and Aspergillus predominant in stems and leaves.Alpha diversity analysis showed that the Shannon,Simpson,and Chao 1 indices were significantly higher in the roots than in the stems and leaves,with leaves exhibiting the lowest diversity(P<0.05).One-way ANOVA revealed significant differences in the fungal community composition of the roots and stems across the three sites(P<0.05)as well as between the roots and leaves at site S3(P<0.001).Spearman correlation analysis indicated a significant positive correlation between fungal communities in stems and leaves within the same site as well as among stems and leaves across different sites(P<0.001).Principal component analysis revealed that the cultivable fungal communities in the stems and leaves were structurally similar across sites,whereas root-associated communities varied significantly among the sampling locations.Overall,this study highlights the rich diversity of cultivable endophytic fungi in P.divaricatum and the clear tissue specificity and geographic preference in their community composition.These findings enhance our understanding of plant-microbe interactions in grassland ecosystems and provide a valuable fungal resource for future studies on bioactive metabolites from endophytes of Mongolian medicinal plants.