稻瘟病在昌黎县,每年都有不同程度的发生,以叶瘟和穗颈瘟为多见,严重时常造成成片枯死和大量白穗,一般减产10～30％,重者达50％以上。 发病条件:在阴雨连绵、湿度大、光照不足、封垄过早、田间荫蔽、肥水管理不当均易发生稻瘟病。一般叶瘟发生在分蘖盛期。穗颈瘟在抽穗后的两天内最易感病。 In Changli County, rice blast occurs in varying degrees every year, which is more common with leaf blast and panicle neck blast. In severe cases, the disease often results in death and large white ears. The yield is reduced by 10-30% and the weight is more than 50%. Disease conditions: in the rainy, humidity, lack of light, seal ridge premature, field shade, fertilizer and water management are prone to rice blast disease. General leaf blast occurred in the tillering stage. Panicle blast in the two days after heading most susceptible.