多种药剂对螺旋粉虱不同虫态的毒力测定

Toxicity of Several Inseccides to Different Stages of Aleurodicus dispersus Russell

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0.9123mg/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、2.5570、3.039 1、3.186 8、4.1895 mg/L。对若虫溴氰菊酯毒力最强,其LC50值为8.5276mg/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、12.9503、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14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。

The toxicity of 30 kinds of insecticides on the adult and 15 kinds of insecticides on the 3rd instar nymph of Aleurodicus 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 beta-cypermethrin 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.