灭幼脲Ⅰ号防治美国白蛾的研究

通过室内生物活性测定和田间防治试验,灭幼脲Ⅰ号对美国白蛾卵死亡率与浓度的关系符合Logistic模型,杀卵效果随日龄延长而下降。施药后2～6天开始大量死亡,浓度在10ppm以上杀虫效果达100％,且具有较长的残效期。若与低浓度敌百虫混用,可加速幼虫死亡,并增效10％左右。

STUDIES ON THE CONTROL OF THE FALL WEBWORM (Hyphantria cunea Drury) WITH DIMILIN-I

Dimlin is a compound of Benzoylphenylurea, and inhibits the synthe-sization of chitin. Through bioassay in the laboratory and control test in the field, Dimilin -I was found to have a logistic equation on the egg mortality of the fall webworm (Hyphantria cunea Drury). The effect on egg mortality decreased with the increase of days of egg development. A large number of larvae of the fall webworm began to die in 2-6 days afterDimilin-I had been applied. The mortality of larvae was 100%when a dosage of dimi- lin of more than 10ppm was applied. Moreover, if Dimilin-I was mixed with Trichlorfon, it could accelerate the death of larvae and increase their mertality by 10%.