短期预测二代粘虫(幼虫)发生量,应从发蛾开始。一般是依据杨树枝的诱蛾量,预报发生面积和虫口密度基本上是准确的;但也有以下问题: 一、可变性大。不同品种的杨树枝条,诱到蛾量不一样。同一棵杨树当年生枝条和多年生枝条,诱到蛾量也不一样,枝把更换次数和间隔时问,诱蛾量也不一样,等等。 Short-term prediction of second-generation armyworms (larvae) occurred, should start from hair moths. Generally based on the amount of trapped moths of poplar branches, the predicted area of ​​occurrence and population density are basically accurate; however, there are also the following problems: First, the variability is large. Different varieties of poplar branches, induced moth is not the same. The same poplar branches and perennial branches, the amount of lure is not the same moth, branches to change the number of times and intervals asked, the amount of lure is not the same, and so on.