氮素营养对冬小麦光合与光呼吸的调节

Regulation of Photosynthesis and Photorespiration by Nitrogen Nutrition in Winter Wheat

以冬小麦扬麦4号为材料,采取不同的施氮水平处理,研究氮素营养对冬小麦光合与光呼吸的调节.用氧电极测定RuBPOase活力.用^(14)C同位素测定RuBPCase活力,用红外线CO_2气体分析仪测定光合和光呼吸强度.结果表明:这些代表整体和酶学水平等几个不同层次的光合参数均随氮素水平的不同而有显著差异,且这些光合参数之间呈极显著的正相关.另外还观察到,光呼吸比光合作用对氮的反应敏感性更强.本文对氮与光呼吸的关系及光呼吸对碳氮代谢的调节机理进行了讨论.

Winter wheat (Yangmai No.4) which was treated with different nitrogen supply was used to study the effects of nitrogen nutrition on photosynthesis and photorespiration. RuBPOase activity, RuBPCase activity, and photosynthetic and photorespiratory rates were measured respectively with O_2 electrode, ^(14)C isotope and infrared CO_2 gas analyzer. The results showed that these photosynthetic parameters which represent whole plant level and enzymatic level varied significartly with nitrogen level. And there are signifi- cant positive correlations among them. It was also discovered that photorespiration was more sensitive to nitrogen nutrition than photosynthesis. The relationship between nitrogen level and photorespiration as well as the photorespiratory regulation roles between carbon and nitrogen metabolism were discussed in the paper.