摘要
利用高效液相色谱及田间试验方法,建立了硝磺草酮在土壤、玉米和植株中残留分析方法,研究了硝磺草酮在土壤和植株中的消解动态规律以及玉米中的最终残留状况.研究结果表明,在0.1—2.0 mg.kg-1质量浓度范围内,硝磺草酮的仪器响应值与质量浓度呈良好的线性关系,相关系数达到0.999以上.通过外标法定量(0.01—0.5 mg.kg-1),硝磺草酮在土壤、玉米和植株中的添加回收率分别达到75.10%—97.74%、80.08%—107.43%、86.49%—103.38%,其变异系数分别为4.01%—10.42%、3.44%—9.05%和3.06%—6.97%,在土壤、玉米和植株中硝磺草酮最低检出浓度均为0.001 mg.kg-1,该方法的灵敏度和回收率均可满足农药残留分析要求.在天津和南京开展的两年两地田间试验结果表明,硝磺草酮在土壤和植株中的残留消解动态规律符合一级动力学反应模型,硝磺草酮在土壤和植株中的残留消解半衰期分别为3.51—3.83 d和2.97—3.07 d.按推荐剂量和1.5倍推荐剂量在玉米上喷施10%硝磺草酮1次,在收获前20 d和收获时采集玉米样品,硝磺草酮最终残留量均低于方法最低检出浓度0.001 mg.kg-1.
A field experiment was conducted for developing a reliable and accurate residual mesotrione in soil, maize plant and maize through HPLC, and the method for the determination of degradation dynamics and final residue of mesotrione was also investigated. The results showed that the linearity of the HPLC mothod was satisfied （R2 〉 0. 999 ） in the concentration range of 1.0--2.0 mg· kg-1. The fortification recoveries of mesotrione in soil, plant and maize varied between 75.10% ---97.74%, 86.49% --103.38% and 80.08%-- 107.43%, respectively, with coefficients of variation of 4.01% --10.42%, 3.06% ---6.97% and 3.44% -- 9.05%, respectively. The limit of quantification of （LOQ） in soil, plant and maize was 〈 0. 001 mg^kg-1. Field experiments revealed that the curve of residue dissipation dynamics of mesotrione in soil and plant accorded with the first-order kinetics equation, and the half-lives of mesotrione in soil and plant were 3.51-- 3.83 d and 2.97--3.07 d, respectively. When the recommended dosage and 1.5 times recommended dosage of 10% mesotrione were sprayed once, the final residue concentrations of mesotrione in maize on the 20th day before harvest time and during the harvest time were both less than the LOQ.
出处
《环境化学》
CAS
CSCD
北大核心
2013年第1期144-149,共6页
Environmental Chemistry
基金
国家自然科学基金项目(21107056)
中央级公益性科研院所基本科研业务费专项
农业部农业科研杰出人才及其创新团队支持资金资助
关键词
硝磺草酮
残留
消解动态
玉米
土壤
mesotrione, residue, degradation dynamic, maize, soil.
