“民以食为天”,我国非常重视粮食生产,2005年中央1号文件着重提出要“进一步抓好粮食生产”“,着力提高单产”,提高水稻单产,在选用高产优质品种的同时,要增施更多的肥料,特别是氮肥,以支持高的产出,这样往往诱发病虫危害,水稻生长的中后期主要病害有:纹枯病、稻瘟病、稻曲病 “People take food for the world”, our country attaches great importance to food production, the central government on the 1st document focused on “to further grasp the grain production”, “focus on improving yields”, improve rice yield, in the selection of high yield and quality varieties at the same time, Increased application of more fertilizers, particularly nitrogenous fertilizers, to support high yields tends to induce pests and diseases. The major diseases in the middle and late stages of rice growth are: sheath blight, rice blast,