Fungal diversity of Festuca sinensis seeds in different geographical populations on the Tibetan Plateau

In this study, 11 germplasm resources of Festuca sinensis were collected from different areas of the Qinghai-Tibet Plateau during the same growing season. The purpose was to identify the species and distribution of seed-borne fungi in Festuca sinensis collected from different geographic locations on the Qinghai-Tibet Plateau and to understand whether the infection rate of endophytic fungi affects their diversity. The fungal strains were isolated, purified, and identified using traditional morphological and molecular biological methods. The effects of environmental factors from the seed collection sites on fungal diversity index were analyzed. The results showed that: 1) A total of 92 culturable fungal strains were isolated from 11 F. sinensis germplasm resources, which were preliminarily classified into 92 fungal species based on morphology. Among these, 50 fungal species were identified, belonging to 20 genera and 14 species. The fungal community mainly consisted of Cladosporium, Fusarium, Didymella, Trichometasphaeria, and Neoascochyta, with Cladosporium being the most abundant genus. 2) There were major differences in fungal species distribution and diversity across different germplasm resources. Redundancy analysis showed that the growing monthly mean precipitation was the primary environmental factor driving changes in the seed-borne fungal community, while the endophytic fungal infection rate had no significant effect on the diversity of seed-borne fungi in F. sinensis (P > 0.05). Overall, the findings revealed that the seed - borne fungi of F. sinensis exhibit diversity. Their distribution and community structure were influenced by the growing monthly mean precipitation, with no significant correlation with the endophytic fungal infection rate.