玉米灰斑病空间流行动态模拟模型组建及传播距离研究

Spatial dynamic model of gray leaf spot of maize epidemic and its theoretic spread distance

以玉米品种郑单958为试材接种灰斑病菌,在田间形成不同发病梯度,分析病害传播的空间流行动态,利用SAS9.13统计软件分别构建病害传播梯度的一维、二维和三维模型。结果表明:1.指数模型和GOMPERTZ模型是沈阳地区玉米灰斑病单向传播梯度的最佳模拟模型;2.高斯模型是模拟病害平行于垄向和垂直于垄向方向传播的最佳模型;3.含有(x2+y2)形式的圆形模型和含有a(x2+y2)+bx+cy+d形式的椭圆形模型是模拟病害在二维平面上传播过程的最佳模型。通过模型推导得到病害的传播距离约20～50m。

According to the principle of plant disease epidemiology, the spatial dynamics of gray leaf spot of maize was studied by artificial inoculation to cause the disease gradient in experimental fields. The spatial dynamic models of gray leaf spot of maize were established by SAS 9.13. The results showed that： 1. Exponential Model and GOMPERTZ Model were the optimum One-Dimensional Model in Shenyang region; 2. Gau-ssian Model was the optimum Two-Dimensional Model; 3. Circular Model and Oval Model were the optimum 3-Dimensional Model. According to the spatial dynamic models, the theoretic spread distances of gray leaf spot of maize were in a range of 20 to 50 m.