超高效液相色谱-串联质谱法测定稻田中肟菌酯及其代谢物的残留

为评价肟菌酯在水稻和环境中的安全性,笔者开展肟菌酯在水稻和稻田环境中的残留量及消解动态研究。笔者进行2年3地田间试验。植株消解动态试验按84.37 g a.i./hm2,土壤、田水消解按562.5 g a.i./hm2各施药1次;最终残留试验按84.37 g a.i./hm2(高剂量)和56.25 g a.i./hm2(低剂量)分别施药3次和4次,水稻收获期采样。结果表明,肟菌酯在田水、土壤和植株中的消解半衰期分别为1.8~7.3天、2.4~9.7天、1.4~12.4天。肟菌酯在土壤、植株、谷壳和糙米中的最高残留量分别为0.293、4.435、8.569、0.901 mg/kg。糙米最终残留量低于CAC规定的最大残留限量(MRL)5.0 mg/kg。

Trifloxystrobin and Its Metabolite Residue in Paddy Field: Measured by Ultra Efficient Liquid Chromatography with Tandem Mass Spectrometry

The paper aims to evaluate the security of Trifloxystrobin in rice and environment. The authors conducted a field experiment in 3 locations for 2 years to study the residues and degradation dynamics of Trifloxystrobin in rice and paddy field. For dissipation trial, Trifloxystrobin was applied at the dosage of 84.37 g a.i./hm2 on rice straw, and 562.5 g a.i./hm2 on soil or paddy water all for once; for final residue trial, Trifloxystrobin was applied at the dosage of 84.37 g a.i./hm2 and 56.25 g a.i./hm2 for 3 and 4 times, respectively; samples were took at harvest time. The results showed that: the degradation half-life of Trifloxystrobin in paddy water, soil and rice straw were 1.8-7.3 days, 2.4-9.7 days, 1.4-12.4 days, respectively; the maximum residue of Trifloxystrobin in soil, rice straw, rice shell and brown rice was 0.293, 4.435, 8.569, 0.901 mg/kg, respectively; the results revealed that the residue of Trifloxystrobin in brown rice was less than the MRL set by CAC (5.0 mg/kg).