Abstract: A simulation model for the prediction and management of rice sheath blight (SIMPMRS) was established based on the experimental data obtained from 1985 to 1990. This model is composed of the submodels of rice growth, initial infection by sclerotia of Rhizoctonia solani AG-1, epidemic prediction of ShB, estimating the number of sclerotium formation, assessment of yield loss caused by ShB, control ef fect of fungicides to ShB and optimal decision. It could simulate the tendency of the disease epidemies, injury degree and control benefit effectively under different environmental factors and different control condi tions as well as make optimal decisions for managing the disease in order to obtain maxmium economic benefits. By validity, reliability, sensitivity test and utilized in a large area production, the model was considerated to be valid, reliable, rational constructure and convenient to use. We also analysed the action way of key factors that influence the disease epidemics inonclick="SelectDisplayDiv('EnDivSummaryMoreSummary','EnDivSummaryMore');DisplaySpanDiv('EnDivSummaryHuanYuan')"> this paper.

Key words: Epidemic prediction, Model, Optimal management, Rhizoctonia solani

摘要： SIMPMRS是一个以水稻生长发育时序为主轴，纹枯病发生、流行及其所致产量损失预测为基础， 栽培管理、药剂控制为管理措施，净收益最大为管理目标的系统模拟模型。其结构由水稻生长发育子模型、病原菌核初侵染子模型、病害流行预测子模型、菌核形成子模型、产量损失估计子模型、防治效应子模型和最优管理决策子模型组成。具预报与管理双重功能，既可进行中长期预报与远程决策，又可进行短期预报和实时决策。经有效性检验及大面积生产应用结果表明，该模型结构合理、逼真性强、应用方便，能有效地指导纹枯病大面积药剂防治和综合治理。

关键词: 水稻, 纹枯病, 流行预测, 管理, 防治