摘要
为评价吡虫啉在小麦中的农药残留安全性,应用HPLC法研究了湖南地区和吉林地区小麦植株上吡虫啉消解动态和小麦中的残留动态规律。样品采用乙腈恒温震荡提取,提取液先经石油醚萃取杂质,再经二氯甲烷萃取吡虫啉,萃取液浓缩后过弗罗里硅土活性炭层析柱净化,高效液相色谱检测分析。结果表明：在0.02、0.05和0.25 mg·kg-13个添加水平下,吡虫啉在麦粒和麦秆中添加回收率为82.17%~103.84%,83.82%~111.39%,变异系数分别为4.30%~6.82%、2.30%~5.98%。在湖南和吉林两地小麦麦秆样品中的吡虫啉均消解较快,半衰期分别为4.53、2.99 d。以推荐使用剂量225 g·hm-2和高剂量337 g·hm-2间隔期7 d施用吡虫啉2和3次,距最后一次施药7和14 d,吡虫啉在小麦籽粒、麦秆中最高残留量为：小麦籽粒0.0291 mg·kg-1;小麦麦秆0.1077 mg·kg-1。参照美国最大允许残留量（小麦0.05 mg·kg-1、小麦秸秆饲料0.5 mg·kg-1）限值,此时收获的籽粒食用是相对安全,小麦秸秆也可安全用作饲料。
In order to evaluate the safety of imidacloprid pesticide residues in wheat,the digestion dynamic and residues dynamic law of imidacloprid in wheat plants in Hunan and Jilin areas were studied with the method of HPLC. The samples with acetonitrile were extracted by constant temperature oscillator,the extracting solution was extracted with petroleum ether to remove impurities and then extracted with dichloromethane,which was purified by Florisil-activated carbon column and detected by HPLC-UVD. The results showed that the spiked recoveries in grain and straw at 0. 02,0. 05 and 0. 25 mg·kg- 1levels were 82. 17 %- 103. 84 %,83. 82 %- 111. 39 %,respectively,and the coefficients of variation were 4. 30 %- 6. 82 %,2. 30 %- 5. 98 %. Imidacloprid in wheat straw samples of Hunan and Jilin areas were both digested faster,the half-life were 4. 53,2. 99 days. The recommended dose of 225 g·hm- 2and high-dose 337 g·hm- 2imidacloprid were applied twice and three times at interval of 7 days,the final maximum residue of imidacloprid in wheat grain and wheat straw harvested after 7 and 14 days were 0. 0291 and 0. 1077 mg·kg- 1. Referring to the United States MRL（ wheat 0. 05 mg·kg- 1,wheat straw feed 0.5 mg·kg- 1）,at present harvested grain consumption was relatively safe,and wheat straw could also be used as feed safety.
出处
《西南农业学报》
CSCD
北大核心
2015年第6期2505-2510,共6页
Southwest China Journal of Agricultural Sciences
基金
农业部农药残留资助基金项目(2012P091)
