Abstract: The resistance to nine insecticides and the sensitivity to seventeen insecticides were evaluated in two field populations of the small brown planthopper(SBPH),Laodelphax striatellus Fallén,collected from Wuxi City,Jiangsu Province and Huzhou City,Zhejiang Province in April 2006.The results detected by topical application showed that Wuxi and Huzhou populations developed high level resistance to imidacloprid(79.6-fold and 44.6-fold),and propoxur(76.6-fold and 40.1-fold),mid-high level resistance to carbaryl(29.8-fold and 45.3-fold),respectively,and remained susceptible or low level resistance to diazinon,fenitrothion,fenobucarb,carbosulfan,etofenprox and fenvalerate(1.4-to 8.1-fold).The assay on toxicities of the 17 insecticides to the third instar nymphs of Wuxi and Huzhou populations by using rice stem dipping method showed that the toxicity of fipronil and butylene-fipronil to SBPH was the highest,with the LC50 values being 0.21-0.41 mg/larva,and the recommended insecticides of field efficacy trial were thiamethoxam,nitenpyram,chlorpyrifos,pymetrozine,isoprocarb and dichlorvos.Furthermore,the resistance management strategies of the small browm planthopper to insecticides were also discussed.

Key words: Laodelphax striatellus, susceptibility, resistance to insecticide, insecticide

摘要： 采用点滴法和稻茎浸渍法分别测定了2006年4月采自江苏省无锡市和浙江省湖州市灰飞虱种群对9种杀虫剂的抗性及17种杀虫剂的敏感性。点滴法测定结果表明,无锡种群和湖州种群对吡虫啉均产生了高水平抗性，抗性倍数分别为79.6倍和44.6倍；对残杀威的抗性倍数分别为76.6倍和40.1倍，属高水平抗性；对甲萘威的抗性倍数分别为29.8倍和45.3倍，属中等-高水平抗性；对二嗪磷、杀螟硫磷、仲丁威、丁硫克百威、醚菊酯、氰戊菊酯的抗性倍数为1.4~8.1倍，属敏感-低水平抗性。毒力测定结果表明氟虫腈、丁烯氟虫腈对无锡和湖州灰飞虱3龄若虫的毒力最高，LC50值为0.21~041 mg/L；噻虫嗪、烯啶虫胺、毒死蜱、吡蚜酮、异丙威、敌敌畏为田间药效试验的推荐用药。还讨论了灰飞虱抗药性的治理。

关键词: 灰飞虱, 敏感性, 抗药性, 杀虫剂