1.缺氮。植株长势不旺,矮小,瘦弱。分枝短小,全株上大下小。2.缺磷。出叶慢,叶片小,呈暗绿色。下部老叶茎及叶柄呈紫红色,根系发育减缓。抗逆性差,不正常早熟。籽粒不饱满,产量下降,出油率低。3.缺钾。植株矮小。最初叶片呈暗绿色,叶缘开始向下卷曲,在干热天气更甚。以后缺钾严重时,叶部外缘出现白色的黄斑,老叶在 Nitrogen deficiency Growing plants are not busy, short, thin. Branches short, whole plant up and down. 2. Phosphorus deficiency. Slow leaves, small leaves, dark green. The lower part of the old leaves and petiole purple, root development slowed down. Poor resistance, not premature. Grain is not full, production decline, low oil yield. 3. Potassium deficiency. Plant short. The first leaves were dark green, leaves began to curl down, even in hot and dry weather. After a serious shortage of potassium, the outer edge of the leaves appear white macula, the old leaves in the