几种杀虫剂对荔蝽平腹小蜂(Anastatus japonicus Ashmead)的影响

经测定,敌百虫对荔蝽平腹小蜂的LC_(50)为17.9ppm.本试验取10ppm作为对该蜂的亚致死剂量,用此剂量处理成蜂1h,成蜂平均寿命为6.4d,而对照组(丙酮处理)平均寿命为30.9d,两者差异极显著;用此剂量处理过的成蜂,寄生率为30.1%。而对照组为47.5%,差异显著.用3种杀虫剂处理寄主卵内不同发育期的平腹小蜂,其中杀虫双、杀灭菊脂对各发育期影响均较小,最高死亡率不超过6%,故在防治果蛀虫时可选择使用;甲胺磷对荔蝽平腹小蜂的卵期、幼虫期和预蛹期可造成20%-30%的死亡率,而且该药残效期长,建议在释放寄生蜂的果园避免使用此药防治害虫.

Effects of Some Insecticides on Anastatus pponicus Ashmead

This paper dealt with the effects of the sublethal dose of Trichlorphon on the longevity and fecundity of Anastatus japonicus and the influence of three kinds of insecticides on various development stages of Anastatus japonicus in their host ovate. As to the wasp, the sublethal dose of Trichlorphon was 10 ppm. After the wasp treated with sublethal dose of Tricholrphon for an hour, its average longevity was 6.4 days, and that of the control group was 30.9 days. The difference between the two groups was significant. Meanwhile, the parasitism rate of the treated wasp was 30.1%, but that of the control group was 47.5%. In inscetarium conditions, after spraying Fenvalerate and Shachongshuang with normal concentration upon host ova parasitized by Anastatus japonicus, the emergence rate of the wasp was more than 94%. Therefore, these two kinds of insecticides could be recommended for the control of fruit borer insect in orchard. Because 20%-30% mortality of the Anastatus japonicus (living in host ovate and being at ovate, larva, prepupa stages) could be caused by spraying Methamidophon with normal concentration, and the residual effect of Methamidophon could last for a longer period, so it is unsuitable for the control of litchi pests while releasing parasitism wasp.