三种新烟碱类杀虫剂在土壤中的残留降解及影响因子  

Residue degradation and influencing factors of three neonicotinoids insecticides in soil

作　　者：宋超[1] 周杨全 李义强[1] 王秀国[1] 徐光军[1] 徐金丽[1] 苏赞[3] 张纪利[3] 胡亚杰[3] 

机构地区：[1]中国农业科学院烟草研究所/烟草病虫害监测与综合治理重点实验室,山东青岛266101 [2]云南省曲靖市烟草公司,云南曲靖655000 [3]广西中烟工业有限责任公司,南宁530001

出　　处：《农药学学报》2016年第6期738-744,共7页Chinese Journal of Pesticide Science

基　　金：国家烟草专卖局重点项目(TS-06-20110039);农业行业财政专项(201203091)

摘　　要：建立了吡虫啉、啶虫脒和噻虫嗪在土壤中的高效液相色谱-串联质谱（HPLC-MS/MS）检测方法。样品经乙腈提取和Qu ECh ERS法净化后,采用HPLC-MS/MS检测,外标法定量,在0.01-1.0 mg/kg添加水平下,3种新烟碱类杀虫剂在土壤中的回收率在89%-103%之间,相对标准偏差（RSD）在1.3%-10.3%之间,定量限均为0.01 mg/kg。采用建立的方法,在室内模拟条件下,研究了土壤微生物、温度、土壤含水量及农药初始浓度对土壤中吡虫啉、啶虫脒和噻虫嗪降解的影响。结果表明：土壤微生物是影响农药残留降解的首要因素,灭菌处理土壤中农药残留降解速率明显低于非灭菌土壤。此外,环境温度、土壤含水量、初始浓度等因素也会对农药残留降解产生不同影响,土壤含水量为最大持水量的60%左右时降解最快,半衰期分别为15.6、7.2和25.8 d;农药初始浓度越高,降解速度越慢;在5-35℃范围内,随着温度的升高,降解速度加快。A new method using HPLC-MS/MS was developed to analyze imidacloprid, acetamiprid and thiamethoxam residues in soil. Samples were extracted with acetonitrile, cleaned up by Qu ECh ERS method, and detected by HPLC-MS/MS with quantification by external standard method. Result shows that when the soil samples were spiked with the above mentioned three neonicotinoids pesticides at levels between 0.01 and 1.0 mg/kg, the average recoveries and the relative standard deviations（RSD）are in conformity with the guideline on pesticide residue analysis method. The limit of quantity（LOQ）of imidacloprid, acetamiprid and thiamethoxam in soil samples were all 0.01 mg/kg. By using this new method, the effects of soil microorganism, temperature, soil humidities and the initial concentration on degradation of imidacloprid, acetamiprid and thiamethoxam were studied under laboratory conditions.The results showed that the soil microorganism was the primary factor influencing the degradation of pesticide, and the degradation rate in sterilized soil was obviously lower than that in the none-sterilized soil. Besides, the degradation rate of pesticide was also influenced by temperature, soil humilities and initial concentration. It was optimal for the degradation of the above three neonicotinoids pesticide when the soil humilities was around 60% FC, and the half-life of imidacloprid, acetamiprid and thiamethoxam were 15.6, 7.2 and 25.8 d, respectively under that condition. The higher the initial concentration, the slower the degradation of the above three neonicotinoids pesticide; The degradation was accelerated significantly when the temperature increased from 5 ℃ to 35 ℃.

关 键 词：新烟碱类杀虫剂 吡虫啉 啶虫脒 噻虫嗪 土壤 残留 降解 影响因子 

分 类 号：TQ450.263[化学工程—农药化工] S482.3[农业科学—农药学]