甲氨基阿维菌素苯甲酸盐微乳剂在甘蓝和土壤中的残留研究及安全使用

Residue and Application Safety Assessment of Emamectin Benzoate in Cabbage and Soil

为评价甲氨基阿维菌素苯甲酸盐及其制剂在甘蓝和土壤使用后的生态环境安全性,指导甲氨基阿维菌素苯甲酸盐的科学合理使用,采用田间试验的方法,对甲氨基阿维菌素苯甲酸盐在甘蓝及土壤中的残留消解动态及最终残留量进行研究,应用高效液相色谱-荧光检测器测定甲氨基阿维菌素苯甲酸盐在甘蓝和土壤中的残留量,并对其在甘蓝上的安全使用进行评价。消解动态试验结果表明:甲氨基阿维菌素苯甲酸盐在土壤中的半衰期为10.2～12.6天,药后28天消解80%以上,在甘蓝中的半衰期为1.9～2.3天,药后7天消解90%以上。最终残留量试验结果表明:2.2%甲氨基阿维菌素苯甲酸盐微乳剂在甘蓝上以3.3ga.i./hm2、4.95ga.i./hm2,连续喷药2～3次,喷药后7天、14天、21天收获的甘蓝中甲氨基阿维菌素苯甲酸盐残留量均未检出(<0.001mg/kg),均低于MRL值0.05mg/kg。因此,按照推荐使用剂量在甘蓝上使用,按采收间隔期7天收获是安全的。

For the evaluation of ecological security of emamectin benzoate after using in cabbage and soil,and guiding emamectin benzoate the scientific and rational use,field experiment was conducted to reveal residual degradation dynamics and the final residues of emamectin benzoate in cabbage and soil,the residues of emamectin benzoate in cabbage and soil were determined by HPLC with FLD,and application safety was assessed.The degradation dynamic test results showed that the half-live of emamectin benzoate in soil was 10.2-12.6 d,more than 80% degradation at 28 th day after application,and the half-live of emamectin benzoate in cabbage was 1.9-2.3 d,more than 90% degradation at 7 th day after application.The final residue tests showed that emamectin benzoate was sprayed for 2 to 3 successive times at application dose 3.3 g a.i./hm 2,4.95 g a.i./hm 2,at 7 th,14 th,21 th after the last application,the final residues of emamectin benzoate in cabbage were all lower than the minimum detection limit.Therefore,preharvest interval was suggested to be 7 days when emamectin benzoate was applied at recommended dosage for cabbage.