萝卜蚜对氰戊菊酯的抗药性汰选及其交互抗性

将田间采回的萝卜蚜种群分成两部分,一部分用氰戊菊酯连续汰选13次,另一部分不用药汰选,连续饲养作对照。汰选前及每汰选3～4次测定1次氰戊菊酯对两种群的毒力。结果表明,对照种群对氰戊菊酯的敏感性增加3.76倍,而汰选种群对该农药的抗药性与汰选前比较增长了163.25倍,与同期饲养对照种群比较,抗性已达613.62。该汰选种群对不含氟的溴氰菊酯和氯氰菊酯存在明显的交互抗性(分别达360.7和53.9倍),对含氟的三氟氯氰菊酯、氟氰菊酯和氟胺氰菊酯也存在交互抗性,但只有7倍左右;而对马拉硫磷、氧化乐果、杀螟松、久效磷和灭多威及菊马混剂没有表现出交互抗性,为进一步探讨萝卜蚜的抗药性治理措施提供了试验依据。

RESISTANCE DEVELOPMENT OF LIPAPHIS ERYSIMI KALTENBACH TO FENVALERATE AND ITS CROSS-RESISTANCE

A population of turnip aphid L. erysimi collected from vegetable field in Beijing suburbs was divided into two portions. One portion was successively treated with fenvalerate for 13 times by means of spray method. The other portion was reared as check,without any treatment. The results showed that the sensitivity of the check portion to fenvalerate increased 3. 76-fold, while the treated portion developed high resistance to the insecticide,its resistance ratios were 163. 25-fold and 613. 62-fold as compared with the LD50s of the population before treatment and the check portion respectively. The fenvalerate-treated portion exhibited obviously cross-resistance to non-fluor ("F")element contained pyrethroids such as deltamethrin and cypermetnrin(360. 7- and 53. 9-fold respectively), but very low (4. 6 - 7. 4-fold) to " F" element contained pyrethroids such as cyhalothrin,flucythrinate and fluvalinate. There were no cross-resistances to a mixture of fenvalerate and malathion as well as to methomyl,omethoate, malathion,fenitrothion and monocrotophos. The results will be useful in the insecticide resistance management of this pest.