黄绿木霉诱变菌株对大豆根腐病镰刀菌的拮抗

ANTAGONISM OF Trichioderma aureoviride MUTANT STRAIN AGAINST Fusarium spp. THE PATHOGEN OF SOYBEAN ROOT ROT

以黄绿木霉(Trichoderma aureoviride)为出发菌株,孢子经紫外线照射,亚硝酸及氯化锂复合处理后获得一株酶活增强的突变株。通过对峙培养与发酵液处理病原菌研究了该诱变株对大豆根腐病几种镰刀菌(Fusagium spp.)的拮抗作用。诱变株经传代30代后,其产酶活性仍保持增强,生防能力有所提高。拮抗试验结果明确了黄绿木霉诱变株对镰刀菌的拮抗机理以生存竞争和接触后对病原菌菌丝破坏的溶菌作用为主,且诱变株产孢速度快,分生孢子梗空间竞争优势强于原始菌株。酶活测定结果表明,诱变株的滤纸酶活提高85.7%,CMC—Na酶活提高26.7%,β- 葡萄糖苷酶活提高130.3%。

An increased cellulose enzyme activity mutant strain, which treated original strain spore of T. aureoviride by UV, Nitrous acid and LiC1 was obtained. The antagonism of this induced mutant strain against Fusariurn spp. pathogen of soybean root rot was studied by means of dual culture and treating pathogen with its metabolite. The result showed： after subculture 30 times, the enzyme activity was increased; the bio-control ability was also improved. The mechanism of this strain mainly including competition and cell lyses; the ability of producing spore of mutant strain was stronger than original one. Detecting different cellulose enzyme activity of these two strains, filter paper enzyme activity, CMC-Na enzyme activity and β-glucosidase activity were increased 85.7% ,26.7%, and 130.3% separately.