家蝇对氯氰菊酯抗性的风险评估与预报

目的 评估家蝇(Musca domestica)对氯氰菊酯抗性风险，预测抗性发展速率。方法 采集自然种群家蝇带回室内饲养，采用点滴法用氯氰菊酯筛选抗性品系，测定LD50；采用Tabashnik的方法测定抗性遗传力和预测抗性发展速率。结果 家蝇在室内饲养并用氯氰菊酯连续筛选了10代，平均存活率54．5％，抗性上升了50倍。测得抗性遗传力h^2为0．1577。据此预测在50％～90％的杀死率的选择压力下，要获得10倍的抗性仅需2．2～4．8代。结论 家蝇对氰氰菊酯抗性上升迅速，10代内抗性遗传力基本稳定。

Risk assessment and prediction of resistance to cypermethrin in housefly (Musca domestica)

ObjectiveTo assess resistance risk to cypermethrin and p redict the rate of resistance development in housefly(Musca domestica).MethodsHouseflies collected from natural group were cult ured in laboratory.Resistant strain to cypermethrin in housefly was obtained while LD 50 was determined with the method of topical application. Based on the method described by Tabashnik(1992),the realized heritability(h 2)to cypermethrin in housefly was estimated and the rate of resistance develo pment was predicted.ResultsContinuously selected with cypermethrin for 10 ge nerations at the average survival percentage of 54 5% in laboratory,the strain of housefly had a 50-fold increase in resistance to cypermethrin.The realized h eritability(h 2)of resistance to cypermethrin in housefly was estimated to be 0 157?7 .The rate of resistance development for 10-fold in the housefl y was predicted based on the estimation of the realized heritability(h 2), and it only needs 2 2-4 8 generations under the selected pressure of mortality ranged 50%-90%.ConclusionThe resistance to cypermethrin in housefly in creased rapidly and the realized h eritability(h 2)was stable in 10 generations.