关键词: 二化螟, 高毒农药, 替代药剂, 昆虫生长调节剂, 拟除虫菊酯, 药效试验, 抗药性监测

Abstract: To provide alternative insecticides for rice insect control,the toxicities against the striped stem borer,Chilo suppressalis of 32 insecticides fallen into seven different classes were evaluated by the topical application method in 2005.Efficacy data showed that seven novel insecticides(abamectin,emamectin bezoate,fipronil,tebufenozide,furan tebufenozide,hexaflumuron and chlorfluazuron) and a few organophosphates(such as phoxim,chlorpyrifos,quinaphos and pyridaphenthion) were potential alternatives for highly toxic pesticides in field trials.In addition,the susceptibilities of four field populations of C.suppressalis to 10 pyrethroids were estimated in laboratory in 2004 and 2005.The results showed that 7 pyrethroids with high fish-toxicity(beta-cyfluthrin,lambda-cyhalothrin,beta-cypermethrin,deltamethrin,S-fenvalerate,alpha-cypermethrin and fenpropathrin) were more effective against C.suppressalis than most of organophosphates.It was also observed that the field population of C.suppressalis from Rui′an,Zhejiang(RA05) showed high levels of resistance to some pyrethroids with high-fish toxicity,such as beta-cyfluthrin,lambda-cyhalothrin,beta-cypermethrin and deltamethrin(their resistance ratios were 166.7,51.9,41.3 and 36.8,respectively),providing the first evidence of the resistance development to pyrethroids in field populations of C.suppressalis,although these high fish-toxicity pyrethroids were banned from using in rice paddy.Three compounds with low fish-toxicity(cycloprothrin,etofenprox and silafluofen) showed higher efficacy against C.suppressalis than triazophos in the triazophos-resistant population(RA05).Therefore,these low fish-toxicity pyrethroids can be considered as candidates for replacing highly toxic organophosphates and resistance management for the rice striped stem borer.

Key words: Chilo suppressalis, highly-toxic pesticide, alternative insecticide, insect growth regulator, pyrethroid, efficacy test, resistance monitoring