五元氨基甲酸酯类农药混合物体系对青海弧菌的毒性特点

以5种氨基甲酸酯类农药涕灭威(ALD)、残杀威(BAY)、呋喃丹(CAR)、灭多威(MET)和抗蚜威(PIR)为研究对象,应用均匀设计射线法设计五元混合物体系共6条射线(U1,U2,…,U6),应用基于发光菌青海弧菌Q67的微板毒性分析法(MTA)系统地考察了5种农药及其混合物的毒性,以浓度加和(CA)为参考模型分析混合物毒性相互作用(协同或拮抗作用)。结果表明,Logti和Weibull函数能较好地拟合5种氨基甲酸酯农药及其混合物对发光菌Q67的浓度-效应数据(R20.99,RMSE0.032);以EC50的负对数值pEC50为毒性指标,5种农药的毒性顺序为BAY(pEC50=2.87)CAR(pEC50=2.67)ALD(pEC50=2.00)MET(pEC50=1.99)PIR(pEC50=1.79);依据CA,五元氨基甲酸酯类农药的6条混合物射线中,有2条呈加和作用,4条呈拮抗作用,其中U2和U4在整条浓度-效应曲线上呈现了明显的拮抗作用,而U3和U6的弱拮抗作用分别发生在混合物浓度的中高浓度区和中低浓度区;五元氨基甲酸酯类农药混合物的毒性与组分灭多威(MET)的浓度比呈良好的负相关关系(r=-0.9238),且线性模型对混合物毒性具有良好的预测能力。

Toxicity Characterstics of Five-Carbamate Pesticide Mixture System towards Vibrio qinghaiensis sp. Q67

Taking five carbamate pesticidies, aldicarb (ALD), baygon (BAY), carbofuron (CAR), methomyl (MET) and pirimicarb (PIR) as mixture components and uniform design ray procedure as design method, the toxicity of the five carbamate pesticides and six rays (U1, U2,…, U6) in the pentabasic mixture system to Vibrioqinghaiensis sp.-Q67 were determined by the microplate toxicity analysis method. Concentration addition (CA) model was ap-plied to analyze the toxicity interaction (synergism or antagonism) within mixture system. The results showed that the two functions, logit and weibull, could well describe the concentration-effect data of the five pesticides and six mixture rays with R2>0.99 and RMSE < 0.032. According to the negative logrithmthe value of median effective concentration (pEC50 ), the toxicity order of the five carbamate pesticides is as follows:BAY (pEC50=2.87)>CAR (pEC50=2.67) >ALD (pEC50=2.00)>MET (pEC50=1.99)>PIR (pEC50=1.79). Based on the results predicted by CA, two of the six carbarmate pesticide mixture rays (U1 and U5) exhibit additvie action and four rays (U2, U3, U4 and U5) show antagonism. In addtion, U2 and U4 show clear antagonism on the whole concentration-response curve, while U3 and U6 diplay weak antagonism at the medium-high and medium-low concentration regins, re-spectively. Toxicity of the five pentabasic mixture rays well negatively correlates with the pi of the component MET (r= -0.9238) and the fitted linear model can well predictes the toxicities of the six mixture rays.