不同龄期和性别德国小蠊对拟除虫菊酯类杀虫剂敏感性的测定

目的测定溴氰菊酯、氯氰菊酯对德国小蠊雌雄成虫和1、3、5龄若虫的毒力,为德国小蠊的化学防治提供更有效的指导。方法广口瓶药膜法。结果德国小蠊对溴氰菊酯和氯氰菊酯的耐药性在不同龄期和性别间存在差异。1龄若虫对溴氰菊酯和氯氰菊酯的耐药性最低,其KT50分别为7．1743min和10．0015min;5龄若虫的耐药性最高,其KT50分别为14．1624min和24．6041min。若虫期,随着龄期的增加,其耐药性逐渐增强。在成虫期,雄成虫的耐药性大于雌成虫,雄成虫对溴氰菊酯和氯氰菊酯的KT50分别为9．6157min和11．7492min。结论5龄若虫的KT50值大于1、3龄若虫和雌雄成虫,雄成虫的KT50大于雌成虫。

Susceptibility of different instars and sexes of Blattella germanica to pyrethroid insecticides

Objective To assay the toxicities of dehermethrin and cypermethrin to male, female adults and the first, third, fifth instar nymphae of Blattella germanica, and to provide the effective instruction for chemical control of B.germanica. Methods The insecticide films in jar was used in this study. Results There was significant difference for the tolerance of B.germanica to deltamethrin and cypermethrin among different instars and different sexes. The tolerance of the first instar nymphae to deltamethrin and cypermethrin was the lowest with the KT50 values of 7.1743 rain and 10.0015 min respectively. The KT50 of the fifth instar nymphae to these two chemicals were 14.1624 min and 24.6041 min respectively, highest in all the instars. The tolerance level of nymphae increased gradually with the development of instars. The tolerance level of male adults was higher than that of female adults. The KT50 of male adults to the two tested chemicals were 9.6157 min and 11.7492 min respectively. Conclusion The v of the fifth instar nymphae to dehermethrin and cypermethrin was the highest. The KT50 of male adults to deheimethrin and cypermethrin was higher than that of female adults.