水稻纹枯病为害捐失及影响因素的研究

本研究以连作早稻为对象,对水稻纹枯病为害损失及品种、氮肥施用量、产量水平、发病时间、病情程度等影响因素进行了六年的研究。组建了多因素损失估计模型。根据损失模型统计分析表明:水稻黄熟期病情指数与稻谷减收率的关系最为密切;六个参试品种基本可归为两类;不同氮肥施用量和不同产量水平在一定范围内对同级别的纹枯病病情所致的稻谷减收率均无显著影响。

STUDIES ON THE DAMAGE OF RICE SHEATH BLIGHT AND THE CONCERNED FACTORS

Study on the damage of rice sheath blight occured in different conditions, variety, Napplication, yield level, pathogenous time, and disease level, had been carried out continuously on early season rice in the past six years. A model of multi-factors-yield-loss assessment was set up. The model indicats themost close relationship between the disease index at rice yellow ripeness stage and the rate of yield decrease. According to the model, six experimental varieties were classified into two types depending upon the yield loss level. Field tests in 2 years show that the suggested model is well reliable. Napplieation and yield level showed no-significant effect on the rate of rice decrease caused by the same disease level.