棉花属于喜钾作物,目前生产上因缺钾而导致的棉花早衰问题日趋严峻.不同棉花基因型的钾营养效率存在显著差异,本文综述了其研究现状,并从钾吸收和利用等方面分析了差异的机制,以期为棉花钾高效育种和栽培提供指导.钾吸收效率高的基因型通常根系发达、根毛较多或生理吸收能力较强(最大吸收速率Imax高、亲和常数Km和维持净吸收的最小钾浓度Cmin低)；钾利用效率高的基因型可实现有限钾的高效运转和再分配,且其生理生化代谢的最低需钾量较小、碳氮代谢较为平衡、清除活性氧的能力较强.文中还提出了需要继续研究的方向.%Potassium (K) is a major plant nutrient with many biochemical and physiological functions. Cotton has a high demand for K. However, widespread K deficiency in cotton occurs in many countries. Cotton varieties differ in their K uptake efficiency. This review accessed the available literature on K uptake and utilization efficiency in cotton related to genotype differences. Genotypes efficient in K uptake may have a larger root system and/or efficient physiological uptake characteristics (such as greater /?? [maximum influx rate], and lower K^ [the Michaelis constant] and C? [the minimum concentration for net uptake]). Furthermore, genotypes efficient in K utilization may have active K transport and remobilization, high net photosynthetic ability, better balance between carbon and nitrogen metabolism, greater ability to scavenge reactive oxygen species, and increased capacity to substitute Na+ for K+. Future research areas regarding K efficiency in cotton are suggested.
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