银杏内生真菌No.1028代谢产物的抗真菌活性及其培养生物学特性

采用无菌技术从银杏茎中分离到一株内生真菌(No.1028),经形态分类学和rDNAITS序列分析研究鉴定为黑孢属Nigrosporasp.,菌丝生长速率法测定结果表明,其代谢产物对重要作物真菌病害病原菌具有明显的抑制作用。离体条件下内生真菌发酵液对番茄早疫病菌、黄瓜枯萎病菌、菜豆炭疽病菌、葡萄炭疽病菌、水稻纹枯病菌、黄瓜立枯病菌均有较强的抑制作用,对上述不同病原菌的抑制率分别为66.7%、48.3%、64.6%、36.5%、57.1%和23.0%。经提取分离得到纯的白色晶体状活性物质。同时也研究了不同碳源、氮源、无机离子对内生真菌No.1028生物学特性和生长的影响,发现玉米粉、黄豆饼粉比较适合其生长和抑菌代谢产物的合成,Na 对抑菌代谢产物的合成有较明显的促进作用。

Anti-fungi activities and cultural characteristics of gingko endophytic fungus No.1028

Endophytic fungus No.1028,was identified as Nigrospora sp. based on morphological study and sequence analysis of rDNA-ITS, isolated from the stem of Gingko biloba L. by aseptic techniques. The metabolites of this endophytic fungus were found to have strong inhibition effect on several crop pathogenic fungi in terms of inhibition rate in hypha growth. The inhibition rates were 66.7%, 48.3%, 64.6%, 36.5%, 57.1%, 23.0% on pathogenic fungi Alternaria solani, Fusarium oxysporum, Colletotrichum lindemuthianum, Colletotrichum gloeosporioides, Thanatephorus cucumeris and Rhizoctonia solani, respectively. The active ingredient was separated and purified out from fermentation liquid of endophytic fungus No.1028. It was white crystalline powder by extraction. The effects of carbon, nitrogen and inorganic ion were studied on the growth and metabolism of this endophytic fungus. Corn starch, soybean starch and Na could obviously promote its growth and metabolism for significantly producing more active ingredients.