戊唑醇、肟菌酯和吡唑醚菌酯在青花椒中的残留行为

Residual Behavior of Tebuconazole,Trifloxystrobin and Pyraclostrobin in Zanthoxylum schinifolium

戊唑醇、肟菌酯和吡唑醚菌酯是青花椒生产中常用的杀菌剂,为评价这3种杀菌剂在青花椒中的残留消解行为,本文建立了超高效液相色谱-串联质谱(UPLC-MS/MS)残留分析方法。通过田间试验,对青花椒叶片和果实中戊唑醇、肟菌酯和吡唑醚菌酯的残留量进行了测定。结果表明,在0.01~0.5 mg/L范围内,戊唑醇、肟菌酯和吡唑醚菌酯的峰面积与其质量浓度之间呈良好的线性关系(R^(2)≥0.99)。在0.02~1.00 mg/kg添加水平下,3种杀菌剂的平均回收率为89.1%~95.4%,相对标准偏差(RSD)为1.7%~5.1%,定量限(LOQ)均为0.02 mg/kg。戊唑醇、肟菌酯和吡唑醚菌酯的消解动态均符合一级动力学方程,半衰期为3.4~4.4 d,且在果实中的残留水平低于在叶片中。在本研究施药剂量下,青花椒果实中戊唑醇、肟菌酯和吡唑醚菌酯的残留量均达到最低定量限,普通人群可安全食用。以上结果可为制定青花椒的农药残留限量标准提供参考依据。

Tebuconazole,trifloxystrobin and pyraclostrobin were commonly used fungicides in the production of Z.schinifolium.In order to evaluate the residual behavior of these three fungicides in Z.schinifolium,the method of ultra performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)for residual analysis was established.The residues of tebuconazole,trifloxystrobin and pyraclostrobin in leaves and fruits of Z.schinifolium were determined by field experiments.The results showed that there was good linear relaitonship(R^(2)≥0.99)between the peak areas of tebuconazole,trifloxystrobin,pyraclostrobin in the range of 0.01-0.5 mg/L.At the spiking levels of 0.02-1.00 mg/kg,the average recoveries of these three fungicides were 89.1%-95.4%,and relative standard deviations(RSD)were 1.7%-5.1%.The limits of quantitation(LOQ)were 0.02 mg/kg.The degradation behavior of tebuconazole,trifloxystrobin and pyraclostrobin were all in accordance with the first-order kinetic equation,and half-lives were 3.4-4.4 d with lower residue levels in fruits than those in leaves.Based on selected application dosage,the residues of tebuconazole,trifloxystrobin and pyraclostrobin in fruits all reached LOQ level,indicating that fruits of Z.schinifolium were safe for the general population.The findings could provide reference for formulating pesticide residue limit standard of Z.schinifolium.