稻瘟病是我省水稻主要病害之一。每年均有一定面积发生,从苗期到穗期均能为害。轻病年仅在部分山区少数地方发生,大流行年全省从山区到平原都很严重,如一九七二年晚稻发病面积达数百万亩,其中自治洲55.3万亩晚稻发生穗瘟19.7万亩,占晚稻总面积35%,黔阳地区91.8万亩晚稻发病面积达50余万亩,长沙县120万亩晚稻发病22.4万亩,损失稻谷 Rice blast is one of the main diseases of rice in our province. Each year a certain area occurs, from the seedling to the spike can harm. Slightly ill year only occurred in a few places in a few mountainous areas, and the whole province from the mountainous area to the plain in the year of the pandemic was very serious. For example, in late 1972, the incidence of late rice reached several million mu, of which, Mu, accounting for 35% of the total area of ​​late rice, 91.8 million mu of late rice in QianYang area incidence of more than 50 acres, 120 mu of Changsha County late rice incidence of 224000 mu, loss of rice