13种农药对美国白蛾三龄幼虫触杀作用研究

Study on contacting toxicity of thirteen pesticides against Hyphantria cunea 3^(rd) instar larvae

在室内利用13种不同类型的农药对美国白蛾三龄幼虫进行了触杀作用研究。结果表明,20%灭多威悬浮剂对美国白蛾击倒速度最快,在24h的致死效果就达100%。而3种拟除虫菊酯类农药和1.1%苦参碱·烟碱水剂在36h对美国白蛾幼虫的致死作用都达到100%,80%敌敌畏乳油在48h的致死作用也达到100%,1.8%阿维菌素乳油4000倍液在72h的触杀效果达到了98.2%。而25%灭幼脲3号悬浮剂和0.3%保硕1号水剂1500～4500倍在72h对美国白蛾的致死作用仅达到12.71%～39.99%,另外2种仿生农药和植物源农药对美国白蛾的致死作用在72h仍然很低;另外,还对13种农药毒力回归方程进行了拟合并计算出了LC50。

Studied contacting death of thirteen pesticides against Hyphantria cunea 3rd instar larvae by immersion testing method in laboratory. The results showed that corrected mortality rate of larvae was quickly reached 100.00% after treatment of 20% methomyl WP in 24 h. And the corrected rate of death was also 100.00% after the treatment of three kinds of chrysanthemum cinerariaefolium and 1.1% matrine, nicotine AW in 36 h, besides, including 80% DDV EC in 48 h. The mortality rate was up to 98.20% with the treatment of 4000-fold 1.8% abamectin Ec in 72 h, while 1500-4500 time 25% chlorbenzuron-Ⅲ WP and 0.3% baoshuo- Ⅰ AS in 72 h only had contact activities of the corrected mortality of 12.71%-39.99% against the pest. And the mortality rate was still lower with the treatment of the other two bionic and botanical pesticides in 72 h. Furthermore, toxticity regression equation of the thirteen pesticides on larvae was fitted well and values of LC50 were calculated.