The toxicity of 30 kinds of insecticides on the adult and 15 kinds of insecticides on the 3rd instar nymph of A leurodicus dispersus were determined by Potter spraying method.The results showed that methidathion,chlorpyrifos, phoxim, malathion, alpha-cypermethrin, deltamethrin, dichlorvos and profenofos had higher toxicity on the adult and 3rd instar nymphs.Methidathion, chlorpyrifos, phoxim, malathion, alpha-cypermethrin, deltamethrin,dichlorvos and profenofos got higher toxicity on the adult with LC50 of 0.912 3, 1.571 4, 1.673 1, 2.248 2, 2.557 0, 3.039 1, 3.186 8 and 4.189 5 mg/L, respectively.Deltamethrin, methidathion, chlorpyrifos, lambda-cyhalothrin and betacypermethrin got higher toxicity on the instar nymph with LC50 of 8.527 6, 11.486 5, 12.950 3, 12.973 8 and 13.7036 mg/L,respectively.The sensitivity of different instar nymph to 8 kinds of insecticides was measured with Potter spraying method.The results indicated that the 1st instar nymph had higher than 2-4 instar nymph, and the 4 instar nymph had the less sensiticity.%采用Potter喷雾法,测定30种杀虫剂对螺旋粉虱成虫与15种杀虫剂对螺旋粉虱若虫的毒力.结果表明:杀扑磷、毒死蜱、辛硫磷、溴氰菊酯、马拉硫磷等对成虫、若虫均具有较高活性.对成虫杀扑磷毒力最强,其LC50值为0.9123 mg/L,毒死蜱、辛硫磷、马拉硫磷、顺式氯氰菊酯、溴氰菊酯、敌敌畏及丙溴磷对成虫毒力均较高,其LC50值分别为1.571 4、1.673 1、2.248 2、2.557 0、3.039 1、3.186 8、4.1895 mg/L.对若虫溴氰菊酯毒力最强,其LC20值为8.527 6 mg/L,杀扑磷、毒死蜱、高效氯氟氰菊酯、高效氯氰菊酯对若虫同样具有较高毒力,其LC50值分别为11.486 5、12.950 3、12.973 8、13.703 6 mg/L.另通过不同龄期若虫对毒死蜱等8种杀虫剂的敏感性测定,发现1～4龄若虫对杀虫剂的敏感性随虫龄增加而降低,1龄若虫最敏感,2龄和3龄若虫的敏感性相当,4龄若虫敏感性最低.
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