一、田边杂草与水稻纹枯病发生的关系水稻纹枯病在田边杂草上的寄主极为广泛,绝大多数的杂草都能被侵染危害。囚此,田边杂草对水稻纹枯病的发生影响极大,据田间调查:距发病田边杂草越近,水稻发病率越高,病情越重:反之,距发病杂草越远,发病率越低,病情越轻,以至无病。这表明田边杂草与发病的关系是极密切的.因为:①田边杂草易于旺盛丛生,密度大,湿度高, First, the edge of the weeds and the occurrence of rice sheath blight Rice sheath blight in the fields of weeds on the vast host of weeds, the vast majority of weeds can be infested. According to field surveys, the closer the weeds to the edge of the field, the higher the incidence of rice and the heavier the disease: on the contrary, the farther away from the weeds, The lower the incidence, the lesser the disease, and even disease-free. This shows that the relationship between the weeds and the incidence of Tanabe is very close.Because: Tanabe weeds easily thrive, dense, high humidity,