Two novel species of Colletotrichum (Glomerellaceae, Glomerellales) from Sichuan Province, China

In recent years, the number of reported species of bamboo-inhabiting fungi worldwide has continued to increase, and the forest regions of Southwest China have become hotspots for the discovery and study of new fungal species. Sichuan Province has abundant, diverse, and widely distributed staple bamboo resources for giant pandas. The stable and healthy bamboo forest ecosystems provide favorable habitats for the colonization and proliferation of bamboo-inhabiting fungi.

In the present study, dead bamboo culms were collected from the Giant Panda National Park in Ya’an City and Aba Prefecture, Sichuan Province, China. Based on morphological characteristics and multilocus phylogenetic analyses (ITS, act, chs- 1, his 3, gapdh, and tub 2), two new species, Colletotrichum abaense and C. phyllostachydis, are described in this paper. Colletotrichum is a globally widespread fungal genus.

Most species in this genus are important plant pathogens, while some can colonize hosts as endophytes or saprobes. This genus comprises multiple species complexes and harbors abundant cryptic species. The discovery of the two new species adds to the germplasm resources and species diversity of bamboo-associated Colletotrichum in China.

In this study, detailed morphological descriptions, illustrations, and comparisons with closely related species are provided. The findings lay a foundation for the exploration of bamboo fungal resources and the taxonomic study of the genus Colletotrichum.