一株能与盾叶薯蓣细胞共培养的内生真菌分离及其生物学特性

bstract: An endophytic fungus which could be co-cultivated with D zingiberensis calli was isolated from the rhizome of D zingiberensis. The studies on the morphological and chemical characterization showed that the fungus could not sporulate on the tested media and the fungus alone could produce diosgenin. An attempt had been made to identify the fungus by molecular methods. Phylogenetic analysis based on ITS1-5.8S rDNA-ITS2 sequence demonstrated that fungus RE0105 formed a cluster together with the genus Libertella with a good statistical support, suggesting a closer similarity between them. Cultural characteristics of the fungus were also investigated in the study. Media rich in organic nutrients were propitious to the growth of fungus RE0105. Calli and calli extracts of D zingiberensis could stimulate growth of the fungus. Treatment of the fungus cultures with 20 μmol/L auxin (NAA or 2,4-D) could promote its growth. The growth of the fungus treated with 200 μmol/L cytokinin (KT or 6-BA) was not improved significantly in comparison to the treated cultures with 20 μmol/L auxins. The favorable carbon and inorganic nitrogen sources were sucrose, glucose, fructose, lactose, xylose and ammonium nitrate. However, the growth of the fungus was inhibited and the morphology of culture RE0105 was also changed in the presence of ammonium chloride or ammonium sulphate.