不同胁迫下郑麦0943的耐低氮高温特性研究OA北大核心CSTPCD

[Objective]To illuminate the physiological mechanism of Zhengmai 0943 to low nitrogen and high temperature tolerance,and provide theoretical basis for breeding high yield and high efficiency wheat variety.[Method]We took Zhoumai 18(a check variety in national regional trial)and Aikang 58(a wide spread variety)as control materials.The gas exchange parameters,chlorophyll fluorescence parameters,nitrogen metabolism and antioxidant enzyme activity,content of reactive oxygen species and malonaldehyde were measured and analyzed under normal treatment,low nitrogen stress treatment,high temperature stress treatment,low nitrogen and high temperature stress treatment.[Result]The effect of low nitrogen on photosynthetic physiology of wheat was significantly greater than high temperature,and the tolerance of different wheat varieties to low nitrogen and high temperature was significantly different.Under the three stress treatments,the net photosynthetic rate(Pn),transpiration rate(Tr),stomatal conductance(Gs),PSHmaximum photochemical efficiency(Fv/Fm),photochemical quenching(qP)and PS Ⅰactivity of Zhengmai 0943 were significantly higher than those of Zhoumai 18 and Aikang 58.On the other hand,the superoxide anion formation rate,hydrogen peroxide(H2O2)and malondialdehyde(MDA)content of Zhengmai 0943 were significantly lower than those of Zhoumai 18 and Aikang 58,showing better resistance to low nitrogen and high temperature.The activities of nitrate reductase(NR),glutamine synthetase(GS),glutamate synthase(GOGAT),superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)of Zhengmai 0943 were significantly higher than those of Zhoumai 18 and Aikang 58.[Result]The effect of low nitrogen on the photosynthetic physiology of wheat was significantly greater than that of high temperature.Zhengmai 0943 had better resistance to low nitrogen and high temperature than the two control varieties,showed higher activity of nitrogen metabolism related and antioxidant enzyme under adversity,and maintained higher photochemical and carbon assimilation efficiency.