Classification Of Psychrotrophic Geomyces And Population Genetics Of Geomyces Pannorum

Special environments results in highly fungal diversity. A large numbers of microbes, including psychrophiles and psychrotrophs, live in the cold environments such as the Polar Regions, high mountains, glaciers, and deep ocean. Geomyces spp. as one of the common groups in the cold environments exists in various ecological systems. In this study, a total of188Geomyces strains were isolated from soil samples collected from Antarctic pole, Arctic pole and Xinjiang, Tibet, Yunnan, Sichuan, Gansu of China, which were identified as Geomyces pannorum, Pseudogymnoascus roseus (telemorph of Geomyces vinaceus) and some Geomyces sp. Isolation rate of P. roseus was70%, a dominant species extensively distributed in the area of high altitude of China; while isolation rate of G. pannorum was81.81%in the frigid polar regions, a dominant species in the area of the Polar Area. After screening based on the growth of three standard temperatures including4℃、10℃and20℃, most of Geomyces isolates isolated from soil samples collected in China belonged to the psychrotolerant fungi, include those isolates from Qinghai-Tibet Highland and only27isolates were psychrotrophilic fungi. Population genetics was analysed with35G. pannorum isolates obtained from the Arctic pole, the Antarctic pole, Xizang, Inner Mongolia, Xinjiang, Xizang, Beijing and Hebei based on DNA sequences of ITS, SPR72, VSP13and their SNPs and the results revealed that clusters on phylogenetical tree was closely respondant with the geographic distribution of G. pannorum isolates. Finally,29fractions, gotten from a G. pannorum isolate obtained from the Antarctic pole, were used to treat4fungal phytopathogens including Colletotrichum gloeosporioides、 Botryosphaeria dothidea、Bipolaris sorokiniana、phoma sp. to screen inhabitors to fungal phytopathogen and the result showed two fractions, RNJ7and RNJ10, had significantly restraining abilities to4fungal phytopathogens. It indicated that metabolites obtained from psychrotrophilic fungi were good antagonistic source to fungal phytopathogens in nature and opened a new field to develop new fungicides.