基于QuEChERS-GC/MS法对土壤和甜菜中精异丙甲草胺的残留降解动态测定  

Determination of Residual Degradation of S-Metolachor Residue in Soil and Sugar Beet by QuEChERS-GC/MS

作　　者：程文亮 宋文钰 王浩东 许同心 吴彩兰[1] 王春娟[1] 杨德松[1] CHENG Wenliang;SONG Wenyu;WANG Haodong;XU Tongxin;WU Cailan;WANG Chunjuan;YANG Desong(Key Laboratory for Oasis Agricultural Pest Management and Plant Protection Resource Utilization/College of Agronomy,Shihezi University,Shihezi Xinjiang 832003,China)

机构地区：[1]石河子大学农学院/新疆绿洲农业病虫害治理与植保资源利用重点实验室,新疆石河子832000

出　　处：《新疆农业科学》2023年第3期706-714,共9页Xinjiang Agricultural Sciences

基　　金：新疆生产建设兵团重大科技计划“机采棉田杂草高效防除技术研发与集成应用”(2018AA006)。

摘　　要：【目的】研究精异丙甲草胺在甜菜及种植土壤中的残留降解动态。【方法】采用QuEChERS-GC/MS法,分析不同深度土壤和甜菜中施用的不同浓度的精异丙甲草胺。【结果】精异丙甲草胺在0.01~1.0 mg/L浓度范围内呈良好线性,相关系数为0.9994,所建立的最小检出限为0.001 mg/kg;平均回收率在84.81%~110.45%,相对标准偏差(RSD,n=3)在1.36%~9.0%。1296、1944、3888 g.a.i/hm^(2)的精异丙甲草胺在0~5、5~10、10~15 cm的土壤以及甜菜中的降解遵循一级动力学方程,不同深度土壤中的残留量随浓度的增加而增加,随时间的延长而降低,不同施用浓度在不同深度土壤中的半衰期为9.12~17.77 d。施用浓度越高,降解速度越慢。在甜菜中的残留量和降解速率都低于土壤,半衰期较土壤中略高,3个浓度在甜菜中的半衰期分别为19.25、26.65和32.85 d。【结论】施用1296和1944 g.a.i/hm^(2)的精异丙甲草胺,收获期在土壤和甜菜中的降解率均能达到90%;施用超剂量3888 g.a.i/hm^(2)的精异丙甲草胺在收获期的降解率会低于80%,精异丙甲草胺在土壤和甜菜中较易降解,属于易降解农药。【Objective】This project aims to clarify the residual degradation dynamics of metolachlor in sugar beet and planting soil.【Method】QuEChERS-GC/MS method was used to study the effects of different concentrations of S-Metolachor in different soil depths and sugarbeet.【Results】The results showed that the S-Metolachorresidue was linear in the concentration range of 0.01-1.0 mg/L with a correlation coefficient of 0.9994.The minimum detection limit was 0.001 mg/kg;the average recovery was 84.81-110.45%,relative standard deviation(RSD,n=3)was between 1.36%and 9.0%.The degradation of S-Metolachorresidue in 0-5,5-10,10-15 cm soil and sugar beet in 1,296,1,944,3,888 g.a.i/hm^(2),following the first-order kinetic equation.The residue in different depth soil increased with the increase of concentration,and decreased with the extension of time.The half-life of different application concentration in different depth soil was 9.12-17.77 d.The higher the application concentration,the slower the degradation rate.The residual amount and degradation rate in sugar beet were lower than that in soil,and the half-life was slightly higher than that in soil.The half-lives of three concentrations in sugar beet were 19.25 d,26.65 d and 32.85 d,respectively.【Conclusion】The degradation rate of S-Metolachlor in soil and sugar beet can reach 90%when 1,296 g.a.i/hm 2 and 1,944 g.a.i/hm^(2)are applied,and is lower than 80%when the dosage of S-Metolachlor is 3,888 g.a.i/hm^(2).From the perspective of degradation rate,S-Metolachlor is easy to degrade in soil and sugar beet,which belongs a kind of degradable pesticide.

关 键 词：精异丙甲草胺 土壤 甜菜 QuEChERS-GC/MS 降解动态 

分 类 号：S566.3[农业科学—作物学]