This study aimed to improve the adaptability of biocontrol Trichoderma in the complicated agricultural environment in where herbicides, insecticides, and fungicides co-exist.Trichoderma harzianum was used as initial strain and induced by atmospheric and room temperature plasma(ARTP). The Trichoderma harzianummutants resistant to both fungicides mancozeb and insecticide dinotefuran were obtained and one with the most double-resistance was named as Th-36. The mutant was subject to further mutation by ARTP and screened on the medium with mancozeb, dinotefuran and herbicide oxyfluorfen. Two mutants with triple-resistance were obtained and named as Th-3-36 and Th-4-B. The toxicity resistance test showed that EC50s of mancozeb for Th-3-36 and Th-4-B were up to 5089.2μg a.i.·mL-1 and 5498.2μg a.i.·mL-1;for dinotefuran up to 758.5μg a.i.·mL-1 and 785.9μg a.i.·mL-1;for oxyfluorfen up to 198.2μg a.i.·mL-1 and 200.3μg a.i.·mL-1respectively. The above values were all higher than the average commercially recommended doses of these pesticides. The screened mutants showed the significant increasing resistance to pesticide, inherited parental broad-spectrum antibacterial property, and presented genetic stability. Furthermore growth capacity and enzyme characteristics of the mutants were better than those of the parental strains.%旨在为提高生防木霉菌对田间除草剂、杀虫剂以及杀菌剂共存的复杂环境的适应性,以生防菌哈茨木霉(Trichoderma harzianum,GIM 3.442)为出发菌株,采用常压室温等离子体的方法对出发菌株进行诱变.结果显示,以杀菌剂代森锰锌和杀虫剂呋虫胺为筛子,选育出对复合农药有良好抗性的诱变菌株.从中挑选双抗性最好的菌株Th-36,以含有杀菌剂代森锰锌、杀虫剂呋虫胺和除草剂乙氧氟草醚的PDA为诱变筛选培养基,再次进行诱变筛选,获得两株具有三抗特性菌株(Th-3-36和Th-4-B).毒力测试表明,抗性菌株Th-3-36和Th-4-B对代森锰锌、呋虫胺和乙氧氟草醚的EC50分别达到5 089.2μg a.i.·mL-1和5 498.2μg a.i.·mL-1、758.5μg a.i.·mL-1和785.9μg a.i.·mL-1、198.2μg a.i.·mL-1和200.3μg a.i.·mL-1,均高于各农药的市售平均推荐使用浓度.筛选到的突变株对农药抗性明显增强、遗传了亲本的广谱抗菌性并具有良好的遗传稳定性,生长繁殖能力和酶学性质优于亲本菌株.
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