木霉生防耐药因子的诱导及其生化特性研究

为了研究以含药(施佳乐)培养基筛选和诱导生防木霉菌株T-21产生耐药性生防蛋白因子———几丁质酶的效果。利用含药(施佳乐)培养基筛选诱导生防木霉菌株T-21产生几丁质酶,通过DEAE 32纤维素柱层析法进行分离纯化,用SDS-PAGE测定其分子量,并分析温度和pH值对酶活力的影响以及耐药酶对灰霉菌的抑制作用。生防木霉菌株T-21对化学农药施佳乐具有一定的抗性,浓度达1 000μg/ml时生长及产孢情况良好。通过分离纯化的几丁质酶,其分子量为45 kD,其最适反应温度为50℃,最适pH值为5.0,对灰霉菌有明显抑制作用。生防木霉菌株T-21产生的几丁质酶,可与化学杀菌剂混合使用,以增强田间的防治效果、减少化学农药的用量,进而减少化学农药对农作物的污染及残留。

Studies on the Induction of Biocontrol Drug-resistant Factor from Trichoderma and its Biochemical Characteristics

The research was constructed to investigate the effects of producing biocontrol protein factor-chitinase from biocontrol Trichoderma strain T-21 which was screened and induced on medicated medium with pyrimethanil.Chitinase was produced from biocontrol Trichoderma strain T-21 on medicated medium with pyrimethanil,separated and purified by DEAE-cellulose column chromatography.Its molecular weight was determined by SDS-PAGE and the effects of temperate and pH value on the enzyme activity and the inhibition effect of drug-resistance enzyme on Botrytis cinerea were analyzed.Biocontrol Trichoderma strain T-21 had certain resistance to chemical pesticide pyrimethanil.When the concentration of pyrimethanil reached 1 000 μg/ml,the growth of strain and the sporulation were good.The purified chitinase had the molecular weight of 45 kD.Its optimum reaction temperature and pH value of chitinase were 50 ℃ and 5.0 respectively and had an obvious inhibition effect on Botrytis cinerea.Chitinase produced by biocontrol Trichoderma strain T-21 could be used with chemical germicide to strengthen the control effect and reduce the dosage of chemical pesticides so as to decrease the pollution and residue of chemical pesticides in crops.