稻瘟病是水稻三大病害之一，广泛分布于世界各稻区，流行年份一般减产１０％～２０％，严重的达４０％～５０％。在水稻生长前期，如果叶瘟严重发生，稻株在孕穗期前枯死，全田呈火烧状。有些稻株虽不枯死，但抽出的新叶不易伸长，植株萎缩，不抽穗，或抽出的穗短小。在水... Rice blast is one of the three major diseases of rice and is widely distributed in various rice regions in the world. Generally, the epidemic rate is reduced by 10% to 20% in the popular year and 40% to 50% in severe cases. In the early stage of rice growth, if the leaf blast occurred seriously, the rice plants died before the booting stage and the whole field was burned. Although some of the rice plants are not dead, the new leaves are not easily elongated, and the plants are atrophied, non-heading, or short of the spike. In water ...