Abstract: Susceptibility levels of whitebacked plathopper (WBPH, Sogatella furcifera Horvath) and brown planthopper (BPH, Nilaparvata lugens Stal) to 13 insecticides were monitored in laboratory by using standard topical application method. The monitoring results during 1987-1991 indicated: (1) Strains of WBPH and BPH were most susceptible to carbofuran, the lowest to malathion. The LD₅₀values fluctuated among years as the two kinds of hoppers were migrant pests. (2) The development of resistance in WBPH population was faster than that of in BPH population. Compared with LD₅₀values of some insecticides of Nagata (1967), WBPH (Zhejiang, 1990) had a 110.56-fold resistance to malathion, 48.90-fold to fenitrothion, and BPH had a 11.61-fold resistance to malathion, 6.11-fold to fenitrothion at the same monitoring method. (3) There was a negative relation between resistance level of BPH population and the local chemical used. (4) There existed a wide variation of toxicity of the different insecticide varieties of the organophosphorous. The toxicity of monocrotophos was more than 10 times as high as that of malathion.

Key words: Insecticide resistance, Monitoring, Nilaparvata lugens, Sogatella furcifera

摘要： 1987～1991年选用有机磷、有机氯和拟除虫菊酯类十三种杀虫剂对白背飞虱和褐飞虱用国际统一标准毒力测定点滴法进行抗药性监涮。结果表明：1)白背飞虱和褐飞虱对呋喃丹最为敏感。对马拉硫磷敏感度最低，LD50值相差上百倍。因两种飞虱均属迁飞性害虫，年度间的测定结果稍有波动；2) 白背飞虱抗药性发展比褐飞虱快，在测定方法和供试昆虫条件基本相同的情况下， 将1990年所测几种药剂的LD50与Nagata (1967)测定的数据进行比较。浙江省白背飞虱种群对马拉硫磷的抗性差异高达1lO．56倍， 对杀螟松为48.90倍；褐飞虱种群对马拉硫磷、杀螟松的抗性分别相差11.61倍和6．11倍。3)褐飞虱种群对药剂的敏感度与当地用药水平呈负相关。4) 有机磷类不同品种杀虫剂对两种飞虱的毒力差异较大。毒力较高的久效磷的LD50值与毒力较低的马拉硫磷的LD50值相差数十倍。

关键词: 杀虫剂, 抗药性, 监测, 白背飞虱