气相色谱-质谱法测定二甲戊灵在棉花和土壤中的残留及消解动态  

Residue and Digestion Dynamics of Pendimethalin in Cotton and Soil by Gas Chromatography-Mass Spectrometry Method

作　　者：李新国 李慧冬 LI Xin-guo;LI Hui-dong(Heze Eco-environment Monitoring Center of Shandong,Heze,Shandong 274000;Institute of Quality Standard and Test Technology for Agro-products,Shandong Academy of Agricultural Sciences,Jinan,Shandong 250100)

机构地区：[1]山东省菏泽生态环境监测中心,山东菏泽274000 [2]山东省农业科学院农业质量标准与检测技术研究所,山东济南250100

出　　处：《安徽农业科学》2020年第22期187-189,共3页Journal of Anhui Agricultural Sciences

基　　金：山东省自然科学基金项目(ZR2016Y027)。

摘　　要：[目的]采用气相色谱-质谱(GC-MS)法测定二甲戊灵在棉花和土壤中的残留及消解动态。[方法]土壤和棉籽样品经过乙腈浸泡,超声波提取,再经过净化后采用气相色谱-质谱(GC-MS)仪测定。[结果]在0.01~0.50μg/mL,二甲戊灵的峰面积(y)与质量浓度(x)有良好的线性关系(r=0.9992)。此方法中二甲戊灵的最低检出限为0.001 ng,添加最低检出浓度为0.01 mg/kg。在0.01~0.50 mg/kg 3个添加水平下,二甲戊灵在棉株中回收率在88.1%~102.0%,RSD为1.64%~2.87%;在土壤中回收率在91.2%~107.0%,RSD为1.62%~4.81%;在棉籽中回收率在97.4%~102.0%,RSD为1.52%~3.64%。消解曲线符合一级动力学方程,在棉株和土壤中的降解半衰期分别为1.43~5.88和5.48~11.50 d。[结论]该研究为二甲戊灵在棉花上合理使用及其MRL值的制定提供基础数据。[Objective]The residue and degradation dynamics of pendimethalin in cotton and soil were determined by gas chromatography-mass spectrometry(GC-MS)method.[Method]Soil and cottonseed samples were soaked in acetonitrile,extracted by ultrasonic wave,purified and determined by phase chromatography-mass spectrometry(GC-MS).[Result]In the range of 0.01-0.50 ug/mL,there was a good linear relationship between the peak area(y)of pendimethalin and the mass concentration(x)(r=0.9992).The minimum detection limit of pendimethalin by the instrument was 0.001 ng and the minimum detection concentration was 0.01 mg/kg.Under the addition levels of 0.01-0.50 mg/kg,the recovery rate of pendimethalin in cotton plants was 88.1%-102.0%,and RSD was 1.64%-2.87%;the recovery rate in soil was 91.2%-107.0%,and RSD was 1.62%-4.81%;the recovery rate in cottonseed was 97.4%-102.0%,and RSD was 1.52%-3.64%.The degradation curve conforms to the first-order kinetic equation,and the degradation half-lives in cotton plants and soil were 1.43-5.88 and 5.48-11.5.0 d respectively.[Conclusion]This study provides basic data for the rational use of pendimethalin on cotton and the formulation of its MRL value.

关 键 词：气相色谱-质谱法 二甲戊灵 棉株 土壤 棉籽 残留 消解动态 

分 类 号：S481.8[农业科学—农药学]