Isolation And Identification Of Endophytic Fungi From Medicinal Plants And Study On Its Culture Characteristics

Endophytes are a kind of plant parasitic fungi, due to the particularity of the living environment, endophytes cooperative coevolution with host plants, in the course of evolution, two factors form a symbiotic relationship. Recent research shows that endophytes not only have antibacterial, antitumor, insecticidal, antiviral, antioxidant activity and also can produce some substances promoting plant growth, such as plant auxin cells, and excited gibberellin directly contributing to the growth of plants. Endophytes are becoming a kind of important resource that people are looking for the new antibacterial antitumor drugs.The materials of the study are mainly the medicinal plant having the antimicrobial activity. We used the materials to isolate the endophytes with antimicrobial activity, then test the antagonist effect of them, identified them by morphology and molecular biology. And we optimized the growth condition of the strain BY-1from chelidonium majus,The experiment results are as follows:Firstly,27strains of endophytes were isolated from seven kinds of medicinal plants such aschelidonium majus, Gynura root and Ranunculus japonicus.Secondly, there were14strains of endophytes having antagonist effect against Alternaria alternata Keissl by screening. The antagonist effect on Alternaria alternata Keissl by the strain BY-1from chelidonium majus, the strain TJ-2from Gynura root and the strain MY-1from Ranunculus japonicus was significant respectively, their inhibitory rates were above50%. Furthermore, conidial suspension and fermentation liquor of the strains BY-1, TJ-2and MY-1have significant antagonist effect on Alternaria alternata Keissl.Thirdly, based on characteristics of morphology, microscopic observation and the analysis of16S rDNA sequence, the homology between TJ-2and Fusarium sp was99%, the strain TJ-2from Gynura rootwas identified preliminarily, belong to Fusarium sp. The strains MY-1^MJ-1-, LJ-3and Bionectria ochroleuca have high homology, the homology was above99%. The strains MY-1、MJ-1from Ranunculus japonicus and the strain LJ-3from Glechoma longituba were identified as Bionectria ochroleuca. The strains SJ-2from Thalictrum aquilegifolium and BY-1from Greater Calandine Herb were identified and they were belong to Bionectria sp, Hypomyces aureo-nitens, Hypocreales, Ascomycetes, Ascomycota.Fourthly, the biological characteristics of the strains BY-1fromchelidonium majus were given in the article. The result showed that the best illumination conditions for the strain are as follows:the basic medium is czapek’s medium, the temperature is25℃, the pH is8, the light condition is12h light and12h darkness and the carbon and nitrogen source are sucrose and glutamic acid respectively.