热带气候下联苯菊酯在甘蓝和土壤中的残留降解动态

研究热带气候下联苯菊酯在甘蓝和土壤中的消解动态和最终残留。样品经乙腈萃取净化后采用毛细管气相色谱法-电子捕获检测器(GC-ECD)进行测定。结果表明,联苯菊酯在甘蓝和土壤中消解速度较快,测得第一次试验,甘蓝中半衰期为7.70d,土壤中半衰期为10.55d,第二次试验,甘蓝中半衰期为8.97d,土壤中半衰期为12.29d。以最大推荐施用剂量和2倍最大推荐施用剂量施用,不同处理测得在最后一次施药后7d甘蓝样品中最大残留量为0.052mg/kg,土壤样品中最大残留量为0.193mg/kg。分析结果表明联苯菊酯是一种使用安全的杀虫杀螨剂。

Residue Analysis and Degradation of Bifenthrin in Cabbage and Soil under Tropical Climate

The degradation and residue of bifenthrin in cabbage and soil under tropical climate were studied. Residues of bifenthrin were extracted from cabbage and soil sample with acetonitrile. After been cleaned up, the final extract was injected into GC with ECD. Bifenthrin dissipated rapidly from cabbage and soil sample, with half-life of 7.70 d and 10.55 d in first time, and 8.97 d and 12.29 d in second time. When bifenthrin was applied according to recommended dosage and twice of the level, the final residues of bifenthrin in cabbage and soil at the 7 days after the last treatment were detected less than 0.052 mg/kg and 0.193 mg/kg. The results showed that bifenthrin is safe in the cabbage and soil under tropical climate.