New endophytic species of Hypocreales (Sordariomycetes, Ascomycota) from the medicinal plant Panax notoginseng in China.

Panax notoginseng is a famous medicinal plant in China. Under forest-based ecological cultivation, its roots harbor a diverse assemblage of endophytic fungi with unique community structures. Some of these fungi can enhance host resistance to diseases and environmental stresses, promote plant growth, and may influence the biosynthesis of medicinal saponins, thereby contributing to host fitness and metabolite regulation. In this study, a total of 188 endophytic fungal isolates were obtained from the roots of P. notoginseng cultivated under a forest-based ecological system in Yunnan Province, China, including 70 isolates belonging to Hypocreales. Three undescribed taxa of Hypocreales were further investigated based on morphological observations and multilocus phylogenetic analyses, resulting in the description of three new species: Trichoderma wenshanense, Clonostachys grandispora, and Thelonectria chlamydosporia. Detailed descriptions, notes, and illustrations are provided for these new species. This study expands the known diversity of endophytic fungi associated with P. notoginseng and provides taxonomically characterized fungal resources for future studies on their potential applications in ecological cultivation and medicinal quality improvement.