蚕豆蚜数量动态预测研究

STUDY ON THE POPULATION DYNAMICS PREDICTION OF BROAD BEAN APHIDS

为害蚕虫的主要蚜种Ａｐｈｉｓ ｃｒａｃｃｉｖｏｒａ Ｋｏｃｈ、Ａｃｙｒｔｈｏｓｉｐｈｏｎ ｐｉｓｕｍ （Ｈａｒｒｉｓ）、Ｍｅｇｏｕｒａ ｊａｐａｎｉｃａ Ｍａｔｓｕｍｕｒａ，在蚕豆生长的季节，其发生发展具有明显的阶段性，即迁入定居、数量波动、扩散蔓延及消退４个阶段。数量动态预测模型；

In the growing season of broad bean, the broad bean aphids , mainly the cowpea aphid Aphis craccivora Koch , Japanese vicia aphid Megoura japonica Matsumura and pea aphid Acyrthosiphon pisum (Harris), undergo four distinct periods, namely, immigration-colonization, quantitative fluctuation, dispersion and reduction. In the prediction model of population dynamics : the core variance 'Vi'increase rate in unit time' has basically embodied the {[R(1- d)]n ( 1 - m) } , main part of the classical population estimation equation P = Pn { [R(1 - d)]n(1 - m)}. Due to all the Vi, infected branch rate, aphid number/100 branches and humidi-ty-temperate coefficient not belong to normal distribution, it is inappropriate to adopt linear regression method for analysis , otherwise the error would be significantly enlarged. Consequently, the data of humidity-temperature coefficient Xe , infected branch rate X, and aphid number/100 branches Xb were then be converted from quantitative to qualitative, before the estimative equation of Vi was developed by regression analysis with qualitative factors , and three emendatory terms , i. e. field types C1 , distribution of varieties C2 and control effect of natural enemies C3 , were added. The integrated equation was as follows :