Abstract: Bamboo forests are widely distributed in Yunnan. Numerous fungi inhabit on bamboo host, most of which are ascomycetes. In this study, the species diversity and distributions of bambusicolous ascomycetes were investigated based on the data collected from central, south, northeast and northwest of Yunnan. Fungal isolation, DNA extraction, sequencing and identification were carried out. Totally, 300 samples were collected, and pure cultures were obtained by using methods of single spore isolation and tissue isolation. Seventy-four species were identified based on molecular analyses. Bamboo ascomycetes distributions of each area of Yunnan were statistically recorded. The research shows that fungal species diversity in the southern area is relatively rich, however, in the northwest of Yunnan, it demonstrates lower due to the high altitude. The species diversities in classes, orders, families and genera were carried out to show that species mainly belong to classes Dothideomycetes, Sordariomycetes and orders Botryosphaeriales, Hypocreales, Pleosporales and Xylariales. The most widely distributed families are Apiosporaceae, Bambusicolaceae, Botryosphaeriaceae, Roussoellaceae and Xylariaceae. Arthrinium, Bambusicola and Roussoella were the most widely distributed genera. Members of Arthrinium and Botryosphaeriaceae are common plant pathogens. The discovery has reference value for plant disease control and resource conservation.

Key words: Ascomycetes, species diversity, Dothideomycetes, Sordariomycetes