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本文证明小麦条锈病显症率的变化主要决定于有效积温。通过田间人工接种试验,观察了累积显症率与累积有效积温的关系,获得数据的相应点图大体呈“S”型曲线分布。选择并建立了Weibull函数、逻辑斯谛模型和函数Y=sin~2(aX+b)(a,b为常数)等三种形式的数学模型,以描述这些点的分布,并比较它们各自的拟合度。认为下面的逻辑斯谛模型最好。其中,PP_i为第i天累积显症率,TT_i为侵入日到调查日(第i天)的累积有效积温。
This paper proves that wheat stripe rust disease prevalence changes mainly depends on the effective accumulated temperature. Through the artificial inoculation experiment in the field, the relationship between the cumulative apparent disease rate and the accumulated effective accumulated temperature was observed. The corresponding point map of the data was generally “S” curve distribution. Three kinds of mathematical models, Weibull function, logistic model and function Y = sin ~ 2 (aX + b) (a and b are constants) are selected and established to describe the distribution of these points and to compare their respective Fitting degree. Think of the following logistic model as the best. Among them, PP_i for the first day cumulative cure rate, TT_i for the invasion of the investigation date (day i) cumulative effective accumulated temperature.