小麦赤霉病流行动态的控制论模型

对小麦赤霉病流行资料进行分析，给出了流行状态微分方程的预测方法．根据不同的状态微分方程，以极大值原理建立小麦赤霉病流行动态的控制论模型，得到流行动态的最优控制轨线．结果表明，气象条件有利，品种感病，药剂防效低，则防治时间应提早．要求消灭病害彻底，防治时间也应提前．药剂防效高，小麦产量高，品种感病，则防治后的净收益就大．以小偃6号为例，给出了Malthus增长型下的病害最优控制轨线和最大净收益．

CYBERNETIC MODELS FOR EPIDEMIC DYNAMICS OF WHEAT SCAB

In accordance with field investigation to epidemic dynamics of wheat scab,the forecast method for differential equations of epidemic state has been given respectively.Based on the Malthus and Weibull differential equations of epidemic state,the cybernetic models of epidemic dynamics of wheat scab were developed according to the extreme value principle,and the optimum control trajectories were given.The results shown that the control time should be moved up under weak disease-resistance of hybrid,lower fungicide effect,and beneficial weather conditions.The higher fungicide effect,severe disease incidence and lower disease-resistance of hybrid will result in great net benefit of control.Under the Malthus growth type,the optimum control and net benefit were given for Xiaoyan No.6.