4种杀虫剂对杞柳瘿蚊幼虫的室内毒力测定和田间药效试验

为了明确4种杀虫剂对杞柳瘿蚊幼虫的防治效果,分别用浸渍法和喷雾法进行了室内毒力测定和田间药效试验。结果表明,20%啶虫脒可溶性粉剂毒杀效果最好,其毒力指数为1 995.43,为当地常规药剂毒死蜱的19.95倍。20%啶虫脒可溶性粉剂、70%吡虫啉水分散粒剂和48%毒死蜱乳油田间防效较好,药后3 d校正防效分别为60.27%、54.80%和40.83%,药后7 d校正防效分别为79.50%、70.71%和58.07%,药后30 d保苗效果分别为59.74%、50.65%和46.75%。在生产上防治杞柳瘿蚊幼虫时,选择药剂可首选20%啶虫脒可溶性粉剂,其次为70%吡虫啉水分散粒剂和48%毒死蜱乳油,可分别按照300 g.hm-2、150 g.hm-2和1 500 mL.hm-2的用量进行田间喷雾。3种药剂交替使用,以延缓害虫抗药性的产生。

Indoor toxicity and field efficacy of four insecticides against the larva of Rhabdophaga salics Schrank

Indoor toxicity and field efficacy were tested with dipping and spraying methods to determine the efficacies of four kinds of insecticides in controlling the larva of Rhabdophaga salics Schrank. The results indicated that 20% Acetamiprid SP had the most significant toxic effect on the larva. Its toxicity index was 1 995.43 and 19.95 times of that of 48% Chlorpyrifos EC, which was used as a regular pharmacy in the local. 20% Acetamiprid SP, 70% Imidacloprid WDG and 48% Chlorpyrifos EC exhibited better control in the field. Three days after spraying, the corrected efficacies were 60.27%, 54.80% and 40.83%, respectively. Seven days after spraying, the corrected efficacies were 79.50%, 70.71% and 58.07%. Thirty days after spraying, the seedling protecting effects were 59.74%, 50.65% and 46.75% respectively. In actual use, 20% Acetamiprid SP, 70% Imidacloprid WDG and 48% Chlorpyrifos EC should be selected to spray at 300 g·hm^-2, 150 g·hm^-2 and 1500 mL·hm^-2, respectively. The three insecticides must be used alternately to postpone the appearance of?insecticide resistance of R. salics.