山区种植水稻常有“坐苗”现象。严重的地区占稻田面积的20%以上。插秧后30—50天株高不及尺,秆瘦小直立,叶片暗绿狭小,俗称“铁丁苗”;也有的苗出现叶片枯黄而有锈簇,老叶尤甚。坐苗时间长,延误了分蘖期,减少了有效穗,产量受到严重影响。坐苗的原因不一,温度和阳 Mountain planting rice often “sit Miao” phenomenon. Serious areas account for more than 20% of the area of ​​paddy fields. 30-50 days after transplanting plant height less than foot, stalk thin erect, dark green leaves narrow, commonly known as “Tieding Miao”; some seedlings appear rusty leaves and rust clusters, especially the old leaves. Sitting seedlings for a long time, delayed the tillering stage, reducing the effective panicle, yield was severely affected. There are different reasons for sitting seedling, temperature and yang