氮形态对不同小麦基因型氮素吸收和光合作用的影响

利用水培试验,研究了3个小麦基因型对不同形态N素吸收和积累的差异.结果表明,在不同N浓度下,小麦对增铵营养和NH⁺的吸收速率显著高于NO₃^-营养,且在较高浓度下,增铵营养处理具有更强的吸收优势.与次敏感型莱州953和钝感型江东门相比,敏感型扬麦158不仅具有较强的NO₃^-和NH⁺吸收能力,而且具有最强的增铵营养吸收能力.增铵营养促进了扬麦158和莱州953对NO₃^-和NH⁺的吸收,但在一定程度上抑制了江东门对NO₃^-的吸收.与NO₃^-营养及NH⁺营养相比,增铵营养显著提高了扬麦158和莱州953的全株、地上部N积累量和叶片光合速率,而对江东门影响较小因此,增铵营养促进了植株的N吸收,提高了N积累和光合速率,从而促进了小麦生长

Effects of nitrogen form on nitrogen absorption and photosynthesis of different wheat genotypes

The experiment was conducted in hydroponics to investigate the difference of three wheat genotypes on nitrogen absorption,accumulation and photosynthesis under three nitrogen forms (NO₃^-,EAN and NH₄⁺).Nitrogen absorption rate of EAN and NH₄⁺ was significantly higher than that of NO₃^- in different nitrogen concentrations.Particularly in higher concentration,EAN had much higher absorption potential than NH₄⁺.YM158,as a sensitive genotype to EAN,had higher absorption rate of NO₃^- and NH₄⁺,and highest of EAN as compared with LZ953 and JDM.EAN highly promoted the absorption of NO₃^- and NH₄⁺ in YM158 and LZ953,but slightly inhibited that of NO₃^- in JDM.Compared with NO₃^- nutrition and NH₄⁺ nutrition,EAN increased nitrogen accumulation in whole plant and aboveground part,and net photosynthetic rate in leaves of YM158 and LZ953,but slightly increased that of JDM.The results indicate that increased growth of wheat under EAN is associated with enhanced nitrogen absorption,increased nitrogen accumulation and net photosynthetic rate.