溴氰虫酰胺及其代谢物在土壤和葱中残留行为

Study on Residue of Cyantraniliprole and Its Metabolites in Soil and Green Onion

论文建立了溴氰虫酰胺及其代谢产物J9238在土壤和葱中残留量的高效液相色谱三重四级杆串联质谱（LC—MS／MS）测定方法，其最小检出量分别为O．1-10。g和0．5-10。g；溴氰虫酰胺和J9238在葱和土壤样品中最低检出浓度均为0．01mg／kg。在0．01—0．1mg／kg添加水平下，溴氰虫酰胺在土壤和葱中添加回收率分别为87．8％～99．3％和79．6％一100．3％，相对标准偏差分别为1．6％一4．6％和5．1％一7．2％；J9238在土壤和葱中添加回收率分别为76．O％～100．8％和77．8％一98．9％，相对标准偏差分别为5．6％～10．o％和4．2％一8．3％，均符合农药残留量分析的要求。同时，为了解100g，L溴氰虫酰胺油悬剂在葱上施用后，溴氰虫酰胺在土壤和葱中的残留消解动态及最终残留状况，在北京和山东两地开展了大田试验研究。结果表明，溴氰虫酰胺在土壤和葱中的残留消解半衰期分别为1．3～2．6d和2．4—4．3d，属于易降解农药。100g／L溴氰虫酰胺油悬剂按推荐剂量和1．5倍推荐剂量在葱中各施药3次和4次，距最后一次施药1d时，溴氰虫酰胺在葱中最高残留量为0．13mg／kg，表明100g／L溴氰虫酰胺油悬剂在葱中使用后，溴氰虫酰胺在葱中的残留量较低。

An analytical method of LC-MS/MS was developed for determining cyantraniliprole and its metabolite, i.e. J9Z38 in soil and green onion. The results showed that the minimum detectable limit of cyantraniliprole and its metabolite in soil and green onion was 0.1~10-9 g and 0.5~10~9 g respectively; average recovery rates of cyantraniliprole in soil and green onion were in a range of 87.8%-99.3% and 79.6%-100.3%, with their relative standard deviations of 1.6%-4.6% and 5.1%- 7.2% respectively; and average recovery rates of J9Z38 in soil and green onion were in a range of 76.0%-100.8% and 77.8%- 98.9%, with their relative standard deviations of 5.6%-10.0% and 4.2%-8.3% respectively. Meanwhile, the characteristics of cyantraniliprole and its metabolite degradation and residue were investigated through the field experiments carded out in Beijing and Shandong Province. The minimum detectable concentrations of cyantraniliprole and its metabolite in soil and green onion were 0.01 mg/kg. Results of the field experiments revealed that the residual dissipation dynamics of cyantraniliprole in soil and green onion conformed to the first order kinetics reaction model; the residual half-life of pyraclostrobin in the soil was 2.6 d （in Beijing） and 4.3 d（in Shandong） respectively; while in green onion 1.3 d（in Beijing）, 2.5 d （in Shandong） respectively. Besides, when 100 g/L cyantraniliprole oil-based suspension according to I- and 1.5-fold recommended dose was sprayed on green onion for 3-4 times at the interval 7 d, the maximum residual value of cyantraniliprole in green onion the next day after spraying was relatively low, 0.13 mg/kg.