阿维菌素对十字花科蔬菜主要害虫的生物活性及防治小菜蛾、菜青虫的田间应用研究

室内毒力测定表明,阿维菌素对菜青虫、小菜蛾、菜蚜有很高的毒力,LC50分别为0.022、0.12和0.28 mg/L;对甜菜夜蛾和斜纹夜蛾的毒力较差,LC50分别为67.56和165.73 mg/L。阿维菌素不影响小菜蛾卵的孵化率。小菜蛾幼虫随虫龄增大,对阿维菌素的敏感性下降。田间试验表明,阿维菌素4 mg/L和8 mg/L对菜青虫和小菜蛾的防效在95%以上,持效期10~15 d。阿维菌素与高效氯氰菊酯(1∶6)、与杀虫单(1∶299)复配对小菜蛾防治有显著的增效作用和良好的田间效果。

Study on the Toxicity and the Effect of Abamectin against Main Vegetable Pests

The result of the test in laboratory showed that the toxicity of abamectin against Pieris rapae (L.) was very high (the LC50 was 0.022 mg/L), the toxicity against Plutella xylostella (L.) (the LC50 was 0.12 mg/L) and Lipaphis erysimi (Kaltenbach) (the LC50 was 0.28 mg/L) was less. That the toxicity of the pesticide was quite bad against Spodoptera exigua (Hübner) and Prodenia litura Fabricius, the LC50 was 67.56 mg/L and 165.73 mg/L, and that the pesticide could not kill the eggs of Plutella xylostella (L.) and the activity to young larvae reduced with increase of larvae age. The result of trial in field stated that control effects of abamectin to Pieris rapae (L.) and Plutella xylostella (L.) at 4 mg/L and 8 mg/L was over 95% and the high effectiveness was maintained for 10~15 days. The binary mixtures of abamectin+beta-cypermethrin(1∶6) and abamectin+monosultap(1∶299) showed synergic activity to Plutella xylostella (L.) and good effect against Pieris rapae (L.) and Plutella xylostella (L.) in field.