水稻白叶枯病的症状及侵染循环问题,1963年早稻分蘖期和孕穗期我们对安仁县的红米桐、衡山粘、贼古粘三个秈稻品种和临武县迟熟中稻无名糯进行田间发病情况调查,发现: 1.在分蘖期病兆最早是从心叶开始观察到的。即心叶抽出时叶片叶鞘上表现有明显白叶枯病症状,解剖有大量白叶枯病菌。再观察其侵染发展过程大致是心叶染病后逐渐扩展至下部和周围叶片的叶尖叶缘再发展到全叶全株以后, Rice bacterial blight symptoms and infection cycle, 1963 early rice at the tillering stage and booting stage We Anlei Red Kme Tong, Hengshan sticky, thief ancient sticky three indica rice varieties and Linwu late immature rice waxy Field incidence survey found that: 1. The first symptom at tillering stage was observed from the heart leaf. That is, when the leaf is drawn out, there are obvious symptoms of leaf blight on the leaf sheath, and a large number of bacterial leaf blight are dissected. Then observe the process of infection and development is roughly the heart leaf disease gradually extended to the lower part of the leaves and the surrounding leaf blade tip after further development of the whole leaf after the whole plant,