除虫菊内生拟盘多毛孢Y1菌株的生物学特性及其对植物病原菌的抑制作用

Biological characteristics and biological activity of Pestalotiopsis sp.obtained from leaf of Pyrethrum cinerariifolium Trev.

从除虫菊叶中分离到1株内生真菌，经形态学和生长特性等研究初步鉴定其为半知菌类拟盘多毛孢（Pestalotiopsissp．）．该菌发酵液的10倍稀释液对苹果炭疽病菌（Glomerellacingulata）、番茄灰霉病菌（BotrytisciFeFea）、玉米大斑病菌（E．rserohilumturcicum）等6种病原真菌的抑制作用均达到85％以上，其5倍稀释液对番茄灰霉病菌、玉米大斑病菌、苹果炭疽病菌的孢子萌发抑制率均达80％以上．盆栽试验中对小麦白粉病（Blumeriagraminis）、番茄灰霉病、黄瓜霜霉病（Lycopersiconesculentum）的防治效果达60％以上．环境和营养因子对该菌的生长繁殖和抑菌活性影响较大：①在10～35℃时，菌丝能生长并形成孢子，最适生长繁殖温度为30℃，孢子的致死温度为65℃；②在pH6．5～8．0时，菌丝生长、孢子形成和萌发均良好，最适pH值为7．5；③能直接利用玉米粉和糊精；④氮源以有机态氮为佳，硝态氮对其生长繁殖有抑制作用；⑤分别以D-木糖、山梨糖、甘露醇为碳源，以硝酸钠、甘氨酸、硫酸铵、牛肉膏、蛋白胨为氯源培养时，该菌株发酵液抑菌活性较高．

An endophytic fungus found from the leaves of Pyrethrum cinerariifolium Trev., was identified as Pestalotiopsis sp. based on its morphological and biological characteristics. The bioassay results show that the inhibition rates of 10 time diluted fermentation liquid of this strain against 6 pathogenic fungi including Glornerella cingulata , Botrytis cirerea , Eacserohilum turcicum, et al ranged from 85.2% to 95. 1%, and those of the 5 time diluted fermentation liquid against B, cirerea, E, turcicum and G, cingulata were more than 80%, The antifungal activity of its fermentation liquid was analyzed by in vivo assay, the prevention and cure effect against Blumeria graminis, B. cinerea and Lycopersicon esculentum were more than 60%. The effect of environmental and nutritional factors on its growth and reproduction was remarkable, i） The temperatures from 10 ℃ to 35 ℃ were suitable for mycelial growth, sporulations and germination. The optimum temperature was 30℃ for sporulation, the lethal temperature was 65 ℃ for 10 minutes, ii） pH value ranged from 6.5 to 8. 0 was favourable for mycelial growth, sporulation and spore germination. The optimum pH was 7.5. iii） The best carbon sources for mycelial growth and sporulations were corn flour or dextrin, iv） As to nitrogen sources, the fungus utilized organic nitrogen very well, while NO3--N （nitrate） inhibited its growth and sporulations, v） Taking D-wood sugar, sorbose, or mannitol as carbon source, with sodium nitrate, glycine, ammonium sulphate, beef extract, or peptone as nitrogen source, the antifungal activity of the fungal fermentation liquid was comparatively high.