稻瘟病是我国的重要病害。其危害程度除因品种、栽培技术外,还与气候条件尤其是温湿度的不同而有差别。在天气阴雨多湿、氮肥多施或高感品种上可以出现“急性型”病斑,其正反面易形成霉层(致病菌);而在天气晴朗、雨水少或抗病品种上形成的 Rice blast is an important disease in our country. Except for varieties and cultivation techniques, the degree of harm is different from the climatic conditions, especially the temperature and humidity. In the weather rainy and humid, nitrogen fertilizer or high susceptibility varieties can appear “acute type ” lesion, its positive and negative form mold layer (pathogenic bacteria); and in clear weather, less rain or disease resistant varieties formed of