防治二代欧洲玉米螟的动态模型

用系统分析的方法组建防治第二代欧洲玉米螟Ostrinia nubilalis(Huboer)的动态模型。系统分为:玉米螟种群动态;玉米生育期与玉米螟之间的物候关系;玉米螟为害玉米后造成的产量损失;以及经济允许为害水平等四个亚系统。模型以田间第二代卵量增长逻辑蒂斯Logistic曲线为基质,并由全代单株累计幼虫密度,当代卵块及高龄幼虫落在某一玉米生育期的比率,各生育期受高龄幼虫为害后所造成的产量损失总和,以及防治效益与消费的比值等八条公式构成。利用这个程序模型,能系统分析玉米螟第二代的发生期、发生量、为害程度和损失,以及预测防治的经济价值,从而作出合理的防治决策。

A PRELIMINARY DYNAMIC MANAGEMENT MODEL FOR THE SECOND GENERATION OF EUROPEAN CORN BORER

A systems approach to the second generation of European corn borer Ostrinia nubilalis (ECB) management was carried out in a ecological laboratory in USA. The system consisted of 4 sub- systems, namely, the population dynamics of ECB, the phenology relationship between the developmental stage of corn and ECB, the yield loss of corn associated with ECB, and the economic injury level of ECB. The model was based on the Logistic curve of egg increaseY%=K/(5.9633-0.3110 X), (R~2=0.9676,SD=0.5170),and conbined with other 7 formulae, such as. the accumulative larvae number per plant in full generation, the ratio of egg and old age larvae in a given staSe of corn, the total yield loss of all stages caused by old age larvae, and the ratio of benifit and cost of control, etc. The programmed model can be used for predicting the time and density of occurrence of ECB, the extent of damage and yield loss, and the expecting economics of control. Consequently, a reasonable management decision can thus be made