草甘膦微生物降解菌株的筛选及其生物学特性

Screening and Biological Characteristics of Strains with Degrading Glyphosate Capacity

为解决草甘膦农药生产和使用过程中产生的环境污染问题提供依据,采用驯化富集培养和平板分离技术对长期施用草甘膦农药的农田和草甘膦农药生产厂家排污口等自然环境中的土壤进行降解菌株的分离与纯化;利用BIOLOG鉴定系统对菌株进行菌种鉴定,并采用紫外分光光度法和平板培养法对菌株降解草甘膦的能力及其生物学特性进行研究。结果表明:从草甘膦农药污染的原生境分离筛选到2株具有高效稳定的草甘膦降解能力的菌株B-1和Y-1,分别为越南伯克氏菌(Burkholderia vietnamiensis)和硝基还原假单胞菌(Pseudomonas nitroreducens/azelaica)。2种菌株在初始pH6.0、6%接种量和30℃培养温度条件下对草甘膦农药的降解效率最佳,在以草甘膦农药(400mg/L)为唯一碳源的MSM培养基中对草甘膦农药的降解率分别为92.64%和87.73%,对3种常见抗生素(Amp,Kan,Chl)均有不同程度敏感。

The strains with degrading glyphosate capacity were isolated and purified from the soils of the farmland with long-term applying glyphosate and the drain outlets of a glyphosate manufacture factory by enrichment culture and plate isolation technique to solve the environmental pollution during the production and use process of glyphosate. The strains with degrading glyphosate capacity were identified by BIOLOG identification system and the degrading glyphosate capacity and biological feature of the isolated strains with degrading glyphosate capacity were analyzed by ultraviolet spectroscopy and plate culture method. Results. B-1 and Y-1 strains with high efficiency and stable degrading glyphosate capacity isolated and screened from the original habitat with glyphosate pollution are identified as Burkholderia vietnamiensis and Pseudomonas nitroreducens/azelaica respectively. The degrading glyphosate effect of two strains is the maximum under the culture conditions of initial pH 6.0, 6% inoculation size and 30℃. The degrading glyphosate rate of B-1 and Y-1 strain cultured on MSM medium containing 400 mg/L of glyphosate as the sole carbon source is 92.64% and 87.73% separately. Two strains are sensitive to three common antibiotics of Amp, Kan and Chl to varying degrees.