棉花打顶是我国各棉区普遍采用的一项整枝技术.它的作用,一是打破主茎顶端生长优势,改变棉株体内养分运输和分配状况,使养分向结实器官集中,供应蕾铃生长;二是控制主茎生长高度,避免出现无效果枝,使中下部果枝上的蕾铃得到充足的养分;三是改善棉田通风透光条件,促进早熟,减轻病虫为害,减少烂铃.所以,打顶有较明显的增加产量和提高品质的效果.但是,打顶是否增产,关键在于掌握好打顶的时间和方法. Topping cotton is a commonly used pruning technique in every cotton area of ​​our country.It has the function of breaking the growth advantage of the top of the main stem, changing the transport and distribution of nutrients in cotton plants, concentrating the nutrients to the harvested organs, ; Second is to control the height of the main stem growth, to avoid ineffective branches, the middle and lower branches of the buds to get adequate nutrients; third is to improve the cotton field ventilation and light conditions, and promote early maturity, reduce pests and diseases, reduce the bad bell. Therefore, Topping has the obvious effect of increasing output and improving quality.However, whether or not topping is increased, the key is to master the time and method of topping.