新疆阿拉尔地区棉铃虫自然种群对常用杀虫剂的敏感水平

SUSCEPTIBILITY OF FIELD POPULATION OF THE COTTON BOLLWORM (HELICOVERPA ARMIGERA ) IN ALAER DISTRICT OF XINJIANG TO CONVENTIONAL INSECTICIDES

用点滴法和浸叶法测定了新疆阿拉尔棉铃虫田间自然种群（ＡＬ种群）３龄、４龄幼虫和初孵幼虫对拟除虫菊酯、有机磷、氨基甲酸酯和有机氯４类１４种常用农药的毒力反应，并与国内外已知敏感基线进行比较。结果表明，该种群处于高敏感水平，３龄幼虫的ＬＤ５０接近内地敏感种群或比内地敏感种群更低；在供试药剂中灭多威、氰戊菊酯、甲基对硫磷、久效磷和辛硫磷相对毒力指数仅为０１６～０５；与印度、澳大利亚、泰国、印度尼西亚等国的敏感品系相比，ＡＬ种群４龄幼虫的ＬＤ５０明显较低。在供试的８种药剂中，除甲基对硫磷外，灭多威、西维因、氯氰菊酯、久效磷、溴氰菊酯、氰戊菊酯、硫丹的相对毒力指数仅为００９～０４。试验还用浸叶法测定了常用杀虫剂对该敏感种群初孵幼虫的毒力基线。

The field population of the cotton bollworm in Alaer district of Xinjiang Uygur Autonomous Region (AL strain) was collected, and its susceptibility to conventional insecticides was tested by topical application to the 3rd and 4th instar larva and by foliar residue method to neonate. It was found that the range of relative toxicity index of the 3rd instar larva to fenvalerate, methyl parathion, monocrotophyos and phoxim was 0.16 to 0.5, indicating AL strain being more susceptible than the population collected from Jiangsu Province. The 4the instar larva, relative toxicity index ranging from 0.09 to 0.4, was also more susceptible to methomyl, carbaryl, cypermethrin, monocrotophyos, deltamethrin, fenvalerate and endosulfan than susceptible strains in India, Indonesia, Australia and Thailand . The base lines of neonate by foliar residue method of AL strain to conventional insecticides were also constructed.