摘要： 在大田条件下，研究了钾素对棉花苗期叶片内源激素与氧自由基代谢的影响。结果表明，施钾有利于提高棉花功能叶片中生长素（IAA）、玉米素核苷（ZR）、赤霉素（GA₃）的含量，降低脱落酸（ABA）的含量，有利于提高IAA/ABA，ZR/ABA，GA₃/ABA之比，延缓棉花功能叶片的衰老。同时，适量施钾肥有利于提高棉花叶片中SOD活性，降低POD活性，减少过氧化物的产生和累积，有利于降低MDA含量，减轻活性氧对细胞膜的伤害。但过量施钾对氧自由基代谢不利。

关键词: 钾素, 棉花, 苗期, 叶片, 内源激素, 氧自由基

Abstract: Effect of potassium nutrition on endogenous hormone and free radicals in cotton leaf during seedling were studied in field condition.The results indicated that potasssium application could increase IAA,ZR and GA₃ content,reduced ABA content,and it seemed that the ratio of IAA/ABA,ZR/ABA,GA₃/ABA could be improved in the treatment with potassium was added,thereby,senescence of cotton function leaf was postponed.Meanwhile,proper potassium application could increase SOD activity,reduced POD activity and decreased peroxide production and cumulation,reduced MDA content,which was beneficial to lower active oxygen injury to cell envelope,but exceessive potassium application was not beneficial to free radicals.

Key words: Potassium, Cotton seedling, Endogenous hormone, Free radical

中图分类号: 

• S562.06