不同供钾水平和氮素形态对棉花功能叶质体色素、碳氮代谢及钾含量的影响

摘要

选择3个不同钾效率基因型棉花品种,在不同供钾水平条件下追施不同形态氮素,研究不同供钾水平和氮素形态对棉花功能叶质体色素、碳氮代谢及钾含量的影响,为合理追施氮肥、提高钾肥利用效率提供理论依据.结果表明,提高供钾水平可增加棉花功能叶质体色素、淀粉、蛋白质及钾含量,降低可溶性糖和游离氨基酸含量.硝态氮肥处理有利于维持吐絮期功能叶叶绿素含量,预防早衰.相比铵态氮肥,硝态氮肥有利于功能叶游离氨基酸和可溶性蛋白的积累,在不供应钾肥或不充分供应钾肥条件下,追施硝态氮肥有利于增加功能叶淀粉含量;在充分供应钾肥条件下,各品种功能叶淀粉含量受氮素形态影响较小,差异不显著.受品种遗传特性的影响,不同钾效率基因型棉花品种功能叶质体色素、可溶性糖、淀粉、游离氨基酸、可溶性蛋白含量存在差异,在棉花生育后期钾高效基因型棉花品种在供钾水平较低的情况下功能叶能保持相对较高的叶绿素含量,延缓叶片衰老.综上,提高供钾水平、追施硝态氮肥有利于增加棉花功能叶质体色素含量,促进碳氮代谢.%The effects of different potassium level and nitrogen forms on plastid pigment and carbon nitrogen metabolism and potassium content of cotton leaves were studied by selecting three genotypes of cotton with different potassium efficiency,so as to provide theoretical basis for the reasonable use of nitrogen fertilizer and increase the efficiency of potassium.The results showed that the contents of potassium and plastid pigment,starch and protein of cotton functional leaves increased,and the contents of soluble sugar and free amino acids of cotton functional leaves reduced with the increase of potassium.The nitrate nitrogen treatment was benefit to maintain chlorophyll content in functional leaves and prevent premature senescence.Compared with ammonium nitrogen,nitrate nitrogen was conducive to the accumulation of free amino acids and soluble protein;nitrate nitrogen was conducive to the increase of starch content under the condition of insufficient or no potassium supply;nitrogen forms had not effect on improving starch content under the condition of sufficient potassium.Due to the heritability of different potassium efficiency genotypes cotton varieties,the contents of plastid pigment,soluble sugar,starch,free amino acid and soluble protein in functional leaves were significantly different.At the later stage of cotton growth,potassium efficient genotypes cotton could maintain relatively high plastid pigment content and delay leaf senescence under the condition of low potassium supply.In conclusion,increasing potassium level and applying nitrate nitrogen fertilizer could increase the content of plastid pigment and promote carbon and nitrogen metabolism in cotton functional leaves.