Endophytic Fungal Diversity And Their Secodary Metabolites Of Eleven Dominant Plant Species In The Dry-hot Valley Of Yuanjiang, Yunnan Province, China

Seven hundred and eight endophytic fungi were isolated from 1147 stems and leaves segments of 11 dominant plant species Atylosia scarabaeoides, Azadirachta indica, Phyllanthus emblica, Broussonetia papyrifera, Sida acuta, Lannea coromandelica, Alysicarpus vaginalis, Calotropis gigantea, Acacia farnesiana, Flemingia philippinensis and Ocimum basilicum, which grow in the dry-hot valley of Yuanjiang county, Yunnan Province, southwest China. The isolation rates of endophytic fungi were between 0.44-0.92. It was found that the isolation rates of endophytic fungi from leaves were significantly higher than that of stems (P=0.043). Based on their morphological characteristics, the isolated fungi were finally identified to 29 taxa including Phomopsis sp., Bipolaris sp. and Alternaria sp. etc, which included 156 mycelia steriles,512 mitosporic fungi and 40 Ascomycetes.Phomopsis, Bipolaris, Peyronellaea, Ascomycetes, Aspergillus and Alternaria were also the dominant fungi of plant species in the dry-hot valley and the percentage of them were 34.18%,8.33%,7.34%,7.06%,3.53%and 2.26%, respectively. The endophytic fungi richness of the 11 plant species was different. The highest endophytic fungi richness appeared in,A. scarabaeoides, P. emblica, S. acuta and O. basilicum, in which 11 taxa were found, whereas, the lowest endophytic fungi richness appeared in L. coromandelica, in which only 5 taxa were found. The results showed that Phomopsis sp.(242,34.18% in all) was the most widely fungi of the dominant plant species in the dry-hot valley, its relative frequency got a range of 12.90% to 68.18%. The diversity of the community composition of endophytic fungi analysis suggested that the endophytic fungal diversity of dry-hot valley plants of Yuanjiang, Yunnan was lower than that of other environmental plant species.243 isolates were screened for their anti Candida albicans activity, and the results showed 29 isolates,11.93% of test strains.29 antifungal trains for secondary sereening, and the results showed that there were 16 trains secodary metabolites of antifungal activities, which the Phomopsis sp. was 13 strains,81.25% of antifungal trains. The higher 0antifungal activities isolates appeared in L.coromandelica and A.farnesiana, the inhibitory circle diameter was between 15-20mm.Compound LX-1 and LX-2 were isolated from the strain J642, which has been identified to be Phomopsis sp. and showed the highest anti Candida albicans activity. Compound LX-2 was identified asβ-D-Glucopyranoside based on its MS and NMR daters but compound LX-1 was still was not identified and still need further work. LX-1 showed anti Candida albicans activity, the inhibitory circle diameter was 16mm.