露地和大棚条件下啶虫脒在黄瓜和土壤中的残留及消解动态

采用乙腈提取、固相萃取净化和高效液相色谱法,分析测定了啶虫脒在露地和大棚2种种植条件下黄瓜和土壤中的残留及消解动态。结果表明:9%啶虫脒可湿性粉剂同时在露地和大棚中按有效成分30.375 g/hm2剂量(推荐高剂量的1.5倍)施药1次,啶虫脒在露地和大棚黄瓜及其土壤中的原始沉积量分别为0.20、0.13 mg/kg和0.29、0.14 mg/kg,露地黄瓜和土壤中的原始沉积量均分别低于大棚;相应地,啶虫脒在黄瓜和土壤中的半衰期分别为9.7、9.4 d(露地)和10.1、11.9 d(大棚)。9%啶虫脒可湿性粉剂同时在露地和大棚中按有效成分20.25 g/hm2和30.375 g/hm2的剂量施药1次和2次,在相同施药剂量、施药次数和采收间隔期情况下,除个别情况外,露地黄瓜中啶虫脒的最终残留量均低于大棚,分别为0.01~0.05 mg/kg(露地)和0.01~0.09 mg/kg(大棚)。

Residue and dissipation of acetamiprid in cucumber and soil under open field and greenhouse conditions

To determine the label use of acetamiprid in cucumber and soil, field experiments were compared in open fields and greenhouse conditions. Acetamiprid residues in cucumber and soil were extracted with acetonitrile, cleaned up with solid phase extraction (SPE). All samples were analyzed by high performance liquid chromatography. Sprayed once with high dosage of 30.375 a.i g/hm², the initial residue concentrations of acetamiprid in cucumber and soil treatment were 0.20, 0.13 mg/kg in open fields, and 0.29, 0.14 mg/kg in greenhouse. The half-life of acetamiprid is 9.7 d in cucumber and 9.4 d in soil in open field, and 10.1 d/11.9 d in greenhouse conditions for cucumber/soil, respectively. Two days after applied one or two times with 20.25 or 30.375 a.i g/hm², the residue of acetamiprid in harvested cucumber ranged from 0.01 to 0.05 mg/kg in open field, and ranged from 0.01 to 0.09 mg/kg in greenhouse. It's found that final residues in cucumber in open fields were generally lower than that in greenhouse under same application conditions.