4种棉蚜抗药性种群的生命力及繁殖力

用4种杀虫剂以浸渍法分别累代处理敏感棉蚜,以选育抗药性。每选育4代进行1次毒力测定及生命力和繁殖力的观察。选育至12代,棉蚜对溴氰菊酯的抗性倍数达4031.4倍,对久效磷、灭多威及硫丹的抗性倍数分别仅为6.3、6.1及4.0倍。棉蚜对溴氰菊酯抗性水平较低时,其生命力及繁殖力略低于敏感品系,随着抗性水平的提高,其生命力和繁殖力也随之增强,RF_(8)接近敏感品系的水平,RF_(12)及RF_(16)则明显超过。灭多威及硫丹抗性种群随抗性水平的提高,其生命力及繁殖力表现不同程度的降低。久效磷抗性种群,各抗性水平下其生命力和繁殖力与敏感品系相比无显著差异。

THE STUDY ON VITALITY AND REPRODUCTIVITY OF FOUR RESISTANT POPULATIONS OF APHIS GOSSYPII

The resistant populations of cotton aphid ( Aphis gossypii) were selected by "immersion method to treat susceptible cotton aphid from generation to generation with four insecticides. Toxicity assay and careful observation of vitality and reproductivity were taken for every four generation. Up to 12 generation, the resistance of population selected with deltamethrin reached 4031. 4-fold (LD50 ratio), while selected with mono-crotophos, methomyl and endosulfan reached only 6.3, 6.1 and 4. 0-fold resistance respectively. The vitality and reproductivity of deltamethrin resistant populations of cotton aphid were lower little than susceptible strain when at lowerly resistant level. But increased gradualy, RF8 were equal and RF12 and RF16 were higher significantly than the susceptible strain with the increase of resistant level. The vitalities and reproductivities of methomyl and endosulfan resistant populations decreased to some extent with the increase of resistant level. There were no significant difference about vitality and reproductivity between monocrotophos resistant populations and susceptible strain of cotton aphid under different resistant level.