草甘膦降解菌的筛选及鉴定

Screening and identification of glyphosate degrading bacteria

目的筛选草甘膦降解菌,并对该菌株进行菌种鉴定。方法以降解率为指标进行初筛,经梯度驯化后计算降解速率和半衰期,选取降解能力最佳的菌株T6,并对菌种进行形态学、生理生化特性以及分子生物学鉴定。结果菌株T6经鉴定为植物乳杆菌,在以草甘膦为唯一碳源的培养基中,24 h降解率达27.51%,降解速率常数为0.0192 h^(-1),半衰期为36.10 h,降解作用良好。结论筛选出一株分解草甘膦农残效果较好的菌株,经鉴定为植物乳杆菌。本研究为开发利用微生物降解草甘膦等农药残留的研究提供一定的理论支持。

Objective To screen glyphosate pesticide residue degrading bacteria and identify the strain.Methods Preliminary screening was performed based on the degradation rate index,and the degradation rate and half-life were calculated after gradient acclimation.The strain T6 with the best degradation ability was selected,and the strain was subjected to morphological,physiological and biochemical characteristics and molecular biology identification.Results Strain T6 was identified as Lactobacillus plantarum.In the medium with glyphosate as the sole carbon source,the degradation rate reached 27.51%within 24 hours,the degradation rate constant was 0.0192 h^(-1),the half-life was 36.10 h,and the degradation effect was good.Conclusion A strain with good effect on decomposing pesticide residues of glyphosate is screened out,and it is identified as Lactobacillus plantarum.The results of this study provide some theoretical support for the development and utilization of microbial degradation of glyphosate and other pesticide residues.