烟草赤星病流行动态预测

2001~2002年对黑龙江省宾县和肇州县两个烟草赤星病田间观测点进行了系统调查,种植烤烟品种为NC89,共计获得了13组田间病害流行数据资料,利用多种增长模型对所得数据进行拟合检验,通过比较决定系数和剩余均方,认为Logistic模型能较好地拟合赤星病田间动态变化过程。分析赤星病发病因素,证明初始病情、日平均温度、日平均相对湿度、日降雨量及降雨日数是影响赤星病发生流行的重要因素,利用逐步回归分析建立了烟草赤星病田间增长速率的预测模型,并对田间病害流行动态进行了预测。

Forecast of Epidemic Dynamic of Tobacco Brown Spot

The investigation of tobacco brown spot in tobacco fields was conducted at Binxian and Zhaozhou counties, Heilongjiang Province, in 2001-2002. The fit of available data to various growth models was tested by comparing determination coefficient and residual mean-square, the results suggested that the logistic model fitted best. Analyzing the causes of the occurrence of tobacco brown spot, it indicated that the primary disease index, daily mean temperature, relative humidity and rain quantity, and number of rainy days were major factors affecting the disease occurrence and epidemic. A predicting model of infection rate in field was founded with stepwise regression analysis, and the epidemic dynamic of tobacco brown spot in field was also forecasted.