9种杀螨剂对朱砂叶螨不同发育阶段的室内毒力测定

室内采用FAO推荐的玻片浸渍法和叶碟法分别测定了9种杀螨剂对朱砂叶螨雌成螨和卵的毒力。结果表明，杀螨活性最高的是阿维菌素，其次是溴虫腈，卡死克、噻螨酮、哒螨灵、三唑锡也具有较好的杀螨效果，炔螨特的杀螨效果较差，甲氰菊酯和氧化乐果的杀螨效果最差；阿维菌素对朱砂叶螨卵的毒力最高，毒力次之的是噻螨酮、哒螨灵、溴虫腈、三唑锡和卡死克，甲氰菊酯、炔螨特和氧化乐果对卵的毒力最差。另外，对朱砂叶螨雌成螨和卵毒力相差最大的是噻螨酮和哒螨灵，毒力分别相差150.27和134.28倍；其次为三唑锡，相差69.80倍；溴虫腈、卡死克、阿维菌素、氧化乐果、甲氰菊酯、炔螨特对卵和雌成螨的毒力差别相对较小。

Toxicities of nine acaricides to Tetranychus cinnabarinus of different developmental stages

Toxicities of nine acaricides to adult females and eggs of Tetranychus cinnabarinus were evaluated in laboratory using slide-dip method and leaf dip method recommende FAO respectively. The results indicat- ed that avermectin was the highest toxicities to adults and the LCso was 0.058 mg/L.The LCs0 was 5.72 mg/L of chlorfenapyr with higher toxities to adults. The LCso of flufenoxuron, hexythiazox, pyridaben and azocyclotin were 12.43-67.01 rag/L, showed good toxicities to adults. The propargite showed the normal toxicities to adults, however, the fenpropathrin and omethoate showed the worst toxicities to adults. The results also showed that the toxicies to eggs from high to low in turn were as following： avermectin, hexythiazox, pyridaben, chlorfenapyr, azocyclotin, fiufenoxuron, fenpropa~hrin, propargite and omethoate. The difference of toxicities between eggs and adults were also studied and the results showed that, the hexythiazox and pyridaben showed the highest difference with 150.27- and 134.28-folds respectively, secondly for azocyclotin with 69.80-folds, other acricides had the relatively small difference with 1.44- to 15.89-folds.