啶虫脒和吡蚜酮对苜蓿蚜虫和蓟马的防效及残留

Control Efficacy of Acetamiprid and Pymetrozine on Alfalfa Aphides and Thrips and the Residues in Alfalfa

为评价20%啶虫脒可溶性液剂和50%吡蚜酮可湿性粉剂对苜蓿蚜虫和蓟马的防效和安全性,采用田间喷雾法和高效液相色谱法测定了两种杀虫剂对苜蓿蚜虫和蓟马的防效及在春季紫花苜蓿中的残留消解动态及最终残留。结果表明,啶虫脒和吡蚜酮在剂量分别为25.0g.a.i/hm^2和187.5g.a.i./hm^2时,药后1~7d对苜蓿蚜虫的防效分别为68.13%~88.72%和87.50%~94.76%,对苜蓿蓟马的防效分别为93.21%~98.33%和78.51%~93.45%,在紫花苜蓿中的半衰期分别为5.36d和2.25d,按推荐使用量施药,药后7d在苜蓿中的残留量均低于0.10mg/kg。

In order to evaluate the control effect of acetamiprid 20% SL and pymetrozine 50% WP on a-phides and thrips in alfalfa and its application safety to alfalfa and environment,the control effect,residual dynamics and final residues of these pesticides in alfalfa grown in open-field in spring were studied with spraying method and high performance liquid chromatography （HPLC）.The control effects of acetamiprid and pymetrozine against alfalfa aphids at dosage of 25.0g.a.i./hm2 and 187.5g.a.i./hm2 in 1~7d after treat-ment were 68.13%~88.72% and 87.50%~94.76%,respectively.The control effects of two insecticides on thrips were 93.21%~98.33% and 78.51%~93.45%,respectively.The half-lives of acetamiprid and py-metrozine were 5.36 and 2.25 days,respectively.According to the recommended dosage application,the fi-nal residue of acetamiprid and pymetrozine in alfalfa were less than 0.10mg/kg on the 7th day.