不同杀虫剂对稻纵卷叶螟的毒效研究

为了解不同杀虫剂对稻纵卷叶螟的毒力，筛选高毒农药的替代药剂，采用Potter喷雾法，对不同杀虫剂对广西南宁稻纵卷叶螟的毒力进行测定研究。结果表明，该地区稻纵卷叶螟对甲氨基阿维菌素苯甲酸盐的敏感性最高，其LC50值为3.4595 mg (a.i.)/L；对氟硅菊酯、三氟氯氰菊酯、辛硫磷、杀虫单、顺式氯氰菊酯、阿维菌素、丙溴磷、三唑磷等杀虫剂敏感性也较高，其LC50值在6.3490~44.8607 mg (a.i.)/L之间。田间试验结果表明，5%氟硅菊酯水乳剂300、450、600 g (a.i.)/hm2对稻纵卷叶螟防效最好，其防效均在80%以上，最高达87.35%；1%甲氨基阿维菌素苯甲酸盐乳油3.6、4.8、7.2 g (a.i.)/hm2和50%杀虫单可湿性粉剂1125、1500、1875 g(a.i.)/hm2，对稻纵卷叶螟也有较好的防效，其防效在66.05%~86.70%之间。

Effects of Different Insecticides Against Cnaphalocrocis medinalis Guenee

The aims were to study the susceptibilities to different insecticides to Cnaphalocrocis medinalis Guenee,and screen alternative insecticides for controlling Cnaphalocrocis medinalis Guenee.The populations of Cnaphalocrocis medinalis Guenee were collected from Nanning in Guangxi Province,and their susceptibilities to different insecticides were tested by spraying method of Potter in laboratory.The results showed that：the populations were the most sensitive to emamectin benzoate,the value of LC50 was 3.4595 mg（a.i.）/L,and were also sensitive to silafluofen,cyhalothrin,phoxim,monosultap,alpha-cypermethrin,avermectin,profenofos,triazophos,the values of LC50 were from 6.3490 mg（a.i.）/L to 44.8607 mg（a.i.）/L.Through field trials,we found that 5% silafluofen EW 300,450,600 g（a.i.）/hm2 had the best effect on the prevention of Cnaphalocrocis medinalis Guenee,the preventing rate of which reached up to more than 80%,with a top of 87.35%.1% emamectin benzoate EC 3.6,4.8,7.2 g（a.i.）/hm2 and 50% monosultap WP 1125,1500,1875 g（a.i.）/hm2 ranked second in this aspect with a rate from 66.05% to 86.70%.