不同药剂对褐飞虱作用特性的比较

为高效和合理利用化学药剂防治褐飞虱Nilaparvta lugens( St(a)l),采用浸苗法和喷雾法测定了噻虫嗪、烯啶虫胺、甲氨基阿维菌素苯甲酸盐、氯噻啉和乙虫腈5种药剂对褐飞虱的作用活性和速度,同时还比较了噻虫嗪和烯啶虫胺对褐飞虱不同龄期若虫的作用活性.结果表明,在5种供试药剂中,从作用活性来看,无论是用浸苗法...

Comparison of the effectiveness of different insecticides against Nilaparvata lugens

The effectiveness of different insecticides,including thiamethoxam,nitenpyram,methylamino-avermectin,imidaclothiz and ethiprole,against the brown planthopper,Nilaparvata lugens（Stl）,was investigated.Lethal concentration and time were determined after seedling-dipping and spraying treatments.Based on dose-mortality responses,nitenpyram showed the highest insecticidical activity against 3rd instar nymphs of all the insecticides tested with LC50 values for seedling-dipping and spray treatments of 0.41 mg/L and 0.26 mg/L,respectively.Imidaclothiz was the least effective insecticide tested.Differences in the performance of the same insecticides between seedling-dipping and spraying treatments were found in methylamino-avermectin,imidaclothiz and thiamethoxam.The killing speed of sprayed methylamino-avermectin,ethiprole and imidaclothiz was significantly higher than that of thiamethoxam and nitenpyram.All instars of the brown planthopper were sensitive to thiamethoxam and nitenpyram,the insecticidical activity ratio of the LC50s of 1st and 5th instar nymphs were 7.4 and 9.7,respectively.