Abstract:

Objective: The main objective of this study is to investigate the diversity and distribution of entomopathogenic fungi in the Western Sichuan Plateau. Method: The soil total DNA, sampled from the samples of 13 different altitudes in the Western Sichuan Plateau, was sequenced by illumina HiSeq sequencing. The composition of fungi community, the species composition of entomopathogenic fungi and their correlation with altitudes were analyzed. Result: 1) At the Phylum level, Ascomycota and Bassiodiomycota together accounted for more than 69% of each altitude sample, which was absolutely dominant. At the Genus level, there were significant differences in the relative abundance of pathogenic fungi among the 13 altitudes, and the most dominant genera were different at each altitude.2) The entomopathogenic fungi detected in 13 soil samples belonged to 18 genera of three families of Hypocreales, among which the dominant species of Clavicipitaceae was Metarhizium, the dominant species of Cordyceps were Isaria and Cordyceps, and the dominant genus of Ophiocordycipitaceae differed in different samples. 3) The ratio of Cordyceps and Isaria in the Hypocreales reached two peaks at 4 300 m and 3 700 m. Conclusion: The diversity of pathogenic fungi is rich and varies at different altitudes in the Western Sichuan Plateau. The entomopathogenic fungi are mainly distributed in three families of Ascomycota Hypocreales, among which the abundance of Cordycipitaceae is significantly different in different altitudes. The abundance of Cordyceps is located at the altitudes of 3 400 m to 4 300 m, while the abundance of Isaria is located at 3 400 m to 3 700 m, indicating that the abundance of Cordycipitaceae is comparatively higher at the altitude range from 3 400 m to 4 300 m.

Key words: Western Sichuan Plateau, entomopathogenic fungi, Hiseq technology, diversity, elevation