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敌百虫粉剂按每平方尺250毫克(折合每亩3斤)的撒粉量,用双重纱格撒粉箱直接撒药于粘虫体上;或先将药粉撒布于盆栽玉米苗上,然后接飼粘虫。結果表明敌百虫粉剂对不同龄期粘虫的药效有明显的不同。在26℃按致死粘虫90％以上所需最低含量計算,直接撒药于虫体,对2龄,3、4龄,或5、6龄,所需浓度依次为0.5％,1.0％或2.5％;玉米苗撒药后飼虫,对以上各龄幼虫所需浓度依次为0.25％,0.5％或1.0％。并表明玉米苗撒布药粉后飼虫的药效,約大出虫体直接撒粉的1倍。将2.5％敌百虫粉剂用这两种方法处理,都能达到或接近100％的效果。温度低至14℃或18℃时,則药效比在26℃或27℃时为低。粘虫取食撒有敌百虫粉剂的玉米叶,在26℃、接近飽和湿度的条件下,对3龄、5龄或6龄粘虫的药效都大于在同温度、相对湿度50％时的药效,而粘虫龄期越大,药效的差别較明显。敌百虫粉剂施后經24小时,其残留药效約相当于刚撒布药粉后的一半。6龄粘虫直接撒布2.5％敌百虫粉剂后,經过不同时間洗除药剂試驗,在24小时內粉剂附着时間越短,药效也越小。
Trichlorfon powder by 250 mg per square foot (equivalent to 3 kg per mu) the amount of dusting, with double gauze powder powder box directly sprinkled on the armyworm body; or first sprinkle the potted corn seedlings, and then Pick up the armyworm. The results showed that the efficacy of trichlorfon powder on armyworm at different ages was significantly different. At 26 ℃, according to the minimum content needed to kill more than 90% of the armyworms, the drug was directly dusted on the worms, and the required concentrations were 0.5%, 1.0% or 2.5 for the 2nd, 3rd, 4th, %; Corn seedling after feeding insects, the above larvae of the above concentrations required were followed by 0.25%, 0.5% or 1.0%. And that maize sprinkling powder after feeding insecticide efficacy, about a large worm directly doused 1 times. Treating 2.5% trichlorfon powder with either method will achieve or close to 100% of the effect. When the temperature is as low as 14 ° C or 18 ° C, the potency is lower than at 26 ° C or 27 ° C. The armyworms fed with trichlorfon powder had higher efficacy at 3, 5, or 6 instar armyworms at 26 ℃ and near saturated humidity than at the same temperature and relative humidity of 50% The efficacy, and the greater the age of the armyworm, the more obvious differences in efficacy. Trichlorfon powder administered after 24 hours, the residual effect of drug equivalent to about half of the powder just after. Immediately after 6th instars of armyworms were sprinkled with 2.5% trichlorfon powder, the medicament was washed at different times and the shorter the powder attachment time was within 24 hours, the smaller the efficacy was.