肟菌酯和戊唑醇在马铃薯种植体系中的沉积和降解行为

The Deposition and Dissipation of Trifloxystrobin and Tebuc on azole in Potato Filed

[目的]系统评价戊唑醇和肟菌酯及其代谢产物肟菌酸在马铃薯种植体系中的沉积、降解、累积等残留行为。[方法]建立了超高效液相色谱-串联质谱(UPLC-MS/MS)残留分析方法,通过残留田间试验,对不同剂量条件下马铃薯植株和块茎中肟菌酯、肟菌酸和戊唑醇的残留量进行了测定。[结果]在0.02-20.0 mg/kg的添加水平下,戊唑醇、肟菌酯和肟菌酸平均添加回收率为78%~103%,相对标准偏差(RSD)为0,6%~7.4%,方法定量限(LOQ)为0.02 mg/kg。肟菌酯和戊唑醇在马铃薯植株中的沉积量随施药剂量增大而增大,消解符合一级动力学方程,半衰期为1.6-3.0d,施药后部分肟菌酯快速代谢为肟菌酸。[结论]选择的施药剂量下马铃薯块茎中肟菌酯和戊唑醇的残留量均小于最低定量限,低于我国和日本规定的最大残留限量,膳食风险处于可接受的安全水平。

[Aims] This study aims to evaluate the residue behaviors of tebuconazole, trifloxystrobin and its metabolite trifloxystrobin acid in potato system. [Methods] An ultra performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) method was developed for the determination of residues in field samples at different doses. [Results] At the spiked levels of 0.02-20.0 mg/kg, the average recoveries of tebuconazole, trifloxystrobin and trifloxystrobin acid were 78-103%, the relative standard deviation(RSD) was 0.6-7.4%, and the limits of quantitation(LOQ) were both 0.02 mg/kg in potato and plant. The half-lives were 1.6-3.0 days, and part of trifloxystrobin metabolized to trifloxystrobin acid rapidly. [Conclusions] The residues of trifloxystrobin and tebuconazole in harvested potatoes were lower than LOQ and the maximum residue limit(MRL) developed by China and Japan. The results showed that the application of trifloxystrobin and tebuconazole at the dosage would not cause unacceptable risk to the health of general population.