【作者】 王林；

【导师】 李文明； 韩丽君；

【作者基本信息】 河南农业大学 ， 农药学， 2014， 硕士

【摘要】 本文采用改进和优化的QuEChERS前处理方法，利用高效液相色谱-串联质谱(HPLC-MS/MS)检测，建立了肟菌酯及其代谢物在土壤、田水以及水稻各个基质中的残留分析方法，同时对肟菌酯在土壤、田水和水稻中的消解规律和最终残留进行了研究，为该农药的安全使用提供了科学的参考依据。样品经乙腈和含0.1‰甲酸水混合溶液震荡提取（田水样品经含0.1‰甲酸的乙腈），经过C18净化后，HPLC-MS/MS进样分析。方法的线性关系良好，肟菌酯和肟菌酸的线性相关系数均大于0.999。肟菌酯在土壤、水稻植株和稻米中的定量限（LOQ）均为0.01mg/kg，在田水、稻壳和稻秆中分别为0.005、0.02、0.05mg/kg；肟菌酸在土壤中的定量限为0.01mg/kg，田水中为0.005mg/kg，水稻植株和稻秆中均为0.05mg/kg，稻米和稻壳中均为0.02mg/kg。肟菌酯在稻田土壤、田水及水稻各基质中的平均回收率为76.5%-103%，相对标准偏差为1.1%-8.9%；肟菌酸为75.1%-105.4%，相对标准偏差为0.9%-15%。肟菌酯的田间残留试验于2012-2013年在北京，湖北，浙江三地进行。消解动态试验结果表明，肟菌酯在稻田土壤、田水和水稻植株样品中的消解符合一级动力学方程Ct=Ct0e-k，消解速度均较快，半衰期分别为1.18-6.22d、0.85-1.47d和5.04-7.33d。最终残留试验中，以最高推荐使用剂量及1.5倍最高推荐使用剂量施药，分别施药3次到4次，14d后收获的稻米中残留量均低于食品法典委员会规定的最大残留限量5mg/kg；稻壳和稻秆中的残留量均低于美国规定的最大残留限量8mg/kg和5mg/kg。肟菌酯和肟菌酸在土壤和水稻中的残留量表现也有所不同，在稻田土壤中的残留量以肟菌酸为主；在稻田水中肟菌酯和肟菌酸均快速消解，二者残留量基本持平；而在水稻植株、稻米、稻壳和稻秆中，残留量以则母体肟菌酯为主，代谢物肟菌酸残留量相对较少。更多还原

【Abstract】 This study is to develope a new analycal methods for determination of trifloxystrobin and itsmetabolite CGA321113in soil, paddy water and rice, and to provide a safer mean. The dissipationdynamic and residue of trifloxystrobin and its metabolite CGA321113in soil, paddy water andrice were also investigated using the established method. A modified QuEChERS method and highperformance liquid chromatograph tandem mass spectrometry (HPLC-MS/MS) were employedfor this study.The method was based on QuEChERS methodology. The samples were extracted usingmixed solution of acetonitrile and acid water (0.1‰formic acid), and purified with C18, finallyanalyzed by HPLC-MS/MS. The results showed a good linearity, and the linear correlationcoefficients of trifloxystrobin and CGA321113were above0.999. The limits of quantification(LOQ) for trifloxystrobin in soil, rice plant and brown rice were0.01mg/L, and0.005,0.02,0.05mg/kg were in paddy water, rice husk and rice straw, respectively. The limits of quantification forCGA321113in soil was0.01mg/kg,0.005mg/kg was in paddy water,0.05mg/kg were in riceplant and rice straw,0.02mg/kg were in brown rice and rice husk. The average recoveries oftrifloxystrobin and CGA321113in paddy soil, water and rice samples were76.5%~103%and75.1%-105.4%, respectively, with the relative standard deviations (RSD)1.1%-8.9%and0.9%-15%, respectively.The field trials of trifloxystrobin were conducted in Beijing, Hubei and Zhejiang province in2012and2013. The results of degradation dynamics trials demonstrated that the dissipation oftrifloxystrobin in soil, paddy water and rice plant were fitted to the first-order kinetics equationCt=C0e-kt, and the half-lives of trifloxystrobin were1.18-6.22d、0.85-1.47d and5.04-7.33,respectively. By spraying3times and4times according to the higest recommended dosage and1.5times higest recommended dosage,14days after spraying, the residues in brown rice werebelow the MRL set by CAC5mg/kg, the residues in rice husk and rice straw were below theMRLs set by USA8mg/kg and5mg/kg, respectively.There are differences in the residues of trifloxystrobin and CGA321113in soil and paddy. Themain residues in soil were CGA321113. Because of quickly degradation, the residues of trifloxystrobin and CGA321113in paddy water were almost same. The main residues in rice plant,rice, rice husk, rice straw were trifloxystrobin, while the amount of CGA321113was relativelylower than trifloxystrobin.更多还原