菜园常用杀虫剂对蝶蛹金小蜂存活和卵巢发育的影响

Effects of insecticides commonly used in vegetable fields on survival and ovarian development of parasitoid, Pteromalus puparum

采用药膜法测定了10种菜园常用杀虫剂对蝶蛹金小蜂Pteromaluspuparum雌成虫存活的影响,以及其中4种杀虫剂对该蜂卵巢发育的影响.结果表明,辛硫磷和乐斯本对该蜂雌成虫的杀伤力极强,处理后2h所有个体死亡,属有害类杀虫剂;敌杀死、除尽和杀虫双处理后48h死亡率达到95%以上,表现出中等毒性;杀灭菊酯处理后48h死亡率为60.0%,为轻度有害类杀虫剂;而万灵、虫螨光和奥绿蔬虫净处理后48h死亡率均不到10%,经抑太保处理的则无个体死亡,表明四者对该蜂的杀伤力较小,均属安全杀虫剂.万灵对该蜂卵巢发育及卵子发生均有较强的抑制作用,虫螨光、奥绿蔬虫净和抑太保三者也有抑制作用,但相对较弱.从充分发挥蝶蛹金小蜂自然控制作用的角度考虑,抑太保、虫螨光和奥绿蔬虫净应是防治菜粉蝶的首选药剂.

Influences of 10 insecticides at commercially recommended dosage on survival of Pteromalus puparum female adults, as well as 4 of them on the ovarian development of surviving adults, were evaluated in laboratory using dry film bioassay. Based upon the mortality of treated adults, phoxim and chlorpyrifos were considered as the most toxic insecticides for female adults of the parasitoid, followed by deltamethrin, chlorfenapyr and bisultap, and fenvalerate as the insecticide of far less toxicity than the formers; abamectin, abamectin-BT, methomyl and chlorfluazuron were fairly safe to this parasitoid. Ovarian development of surviving adults was repressed considerably by methomyl, but evidently less by abamectin, abamectin-BT and chlorfluazuron. In terms of enhancing control efficacy of P. puparum, abamectin, abamectin-BT and chlorfluazuron are recommended as insecticides of first priority for chemical control of Pieris rapae.