防治水稻二化螟的高毒农药替代药剂的室内筛选

为了筛选防治水稻二化螟的高毒农药替代药剂，采用点滴法测定了7类32种药剂对不同水稻生态区二化螟种群的室内毒力。基于这些毒力数据，推荐对二化螟毒力较高的7种新型农药（氟虫腈、阿维菌素、甲氨基阿维菌素苯甲酸盐、虫酰肼、呋喃虫酰肼、氟铃脲和氟啶脲）和一些中低毒性的有机磷品种（如辛硫磷、喹硫磷、毒死蜱和哒嗪硫磷）作为大田药效试验的候选替代药剂。评估了田间二化螟对10种拟除虫菊酯类杀虫剂的敏感性，发现7种对鱼高毒的拟除虫菊酯类杀虫剂（高效氟氯氰菊酯、λ 高效氯氟氰菊酯、溴氰菊酯、高效氯氰菊酯、顺式氯氰菊酯、甲氰菊酯和S 氰戊菊酯）对二化螟的毒力高于大多数有机磷类农药。虽然我国禁止上述菊酯类杀虫剂在水稻上使用，但是浙江瑞安田间种群（RA05）已对高效氟氯氰菊酯、溴氰菊酯、高效氯氰菊酯和λ 高效氯氟氰菊酯等产生高水平抗性（抗性倍数分别为166.7、51.9、41.3和36.8倍）。对鱼低毒的3种菊酯类农药（乙氰菊酯、醚菊酯和氟硅菊酯）对抗性二化螟（RA05）的毒力高于三唑磷。因此，可考虑将这些对鱼低毒的菊酯类农药作为防治水稻二化螟的高毒农药的替代药剂和抗性治理的轮换品种。

Laboratory Screening of Alternative Insecticides for Highly Toxic Insecticides Against the Striped Stem Borer (Chilo suppressalis) on Rice

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.