水稻稻瘟病的发病条件是低温多雨，水稻易染病，品种抗病性低。适温高湿，有雨、雾、露存在条件下有利于发病，尤其在低温多湿、大雾等天气容易发生。氮肥施入过多也易导致病害。病菌以分生孢子和菌丝体在稻草和稻谷上越冬，次年生地 Identification of rice blast disease conditions is low temperature and high humidity, especially during continuous low temperature and rainy weather before rice heading. 病菌以分生孢子和菌丰满体在稻草和稻谷上越冬，次年 Associating with the identification of rice blast disease conditions, the pathogens overw palms on rice straw and grains, and attractive 分生孢子借风雨传播到稻株上，萌发侵入寄主向邻近细胞扩展发病，形成中心病株。病部形成的分生孢子，借风雨传播进行再侵染。
