【摘要】 利用诱捕法从土壤中分离得到 18株木霉 (Trichodermasps.)菌株 ,采用对峙法从中测定、筛选出一株对烟草赤星病菌 (Alternariaalternata)具有极强拮抗作用的菌株 (Tv - 1)。光学显微镜及透射电镜观察结果表明 ,Tv - 1菌株的拮抗机制主要为生长竞争、寄生作用以及产生抗菌素类物质使病菌菌丝消解 ,表现为Tv - 1菌株菌丝生长迅速 ;能附着、缠绕于病菌菌丝上 ,并产生吸器侵入菌丝 ;同时还能分泌使病菌菌丝原生质浓缩、断裂、消解的物质更多还原

【Abstract】 By the method of baiting, 18 isolates were obtained ,and further identificatied as Trichoderma viride. The antagonistic tests of all these isolates to 7 strains of Alternaria alternata from diseased tobacco leaves from different area of Yunnan were carried out by pairing culture on PDA. The results showed that 1 isolated (Tv 1) was strong antagonistic. The examination of antagonistic mechanism under optical microscope and transmission electron microscope showed Tv 1 hyphae growed quickly. Its hyphae could adhere to, coil around the hyphae of pathogen. Its finger shaped haustorium penetrated into the hyphae of Alternaria alternat. Tv 1 could also secret antibiotic substance to make the pathogan hyphal plasma contracted, vacuolated and disrupted.更多还原