棉花是我国主要经济作物之一,但产量不高,究其原因,主要是肥料施用不合理。近几年不少棉农重化肥轻有机肥、重追肥轻基肥、重氮肥轻磷钾肥等不合理的施肥习惯,加剧了棉株养分的失调。棉叶是棉株对体内营养代谢反应最敏感的器官,当某些营养元素缺乏或供应不足时,就会影响棉花的正常代谢活动,并且首先在棉叶上表现出来,如叶片变小、失绿变黄等现象。现将在大田生产中观察和了解到的棉株因缺乏氮、磷、钾、 Cotton is one of the main cash crops in China, but the yield is not high. The reason is that the application of fertilizer is unreasonable. In recent years, many farmers of heavy chemical fertilizer light organic fertilizer, re-fat fertilizer, light fertilizer, nitrogen and phosphorus fertilizers and other unreasonable fertilization practices, aggravating the imbalance of nutrients in cotton plants. Cotton leaves are the most sensitive organs for cotton plant metabolism and metabolism. When some nutrients are deficient or under-supplied, they will affect the normal metabolic activity of cotton and appear on cotton leaves first. Green yellow and so on. Now in the field of production observed and learned that cotton plants due to the lack of nitrogen, phosphorus, potassium,