【摘要】 【目的】揭示施氮量对冬小麦旗叶叶片衰老及其活性氧代谢的影响,为冬小麦的合理施氮提供理论依据。【方法】设置4个施氮梯度(0,138,276和345 kg/hm2),测定分析各施氮处理冬小麦旗叶叶绿素和丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性及可溶性蛋白质含量等指标的变化规律。【结果】在小麦开花后各时期,4个施氮处理中,以276 kg/hm2处理冬小麦旗叶叶绿素含量最高,叶片衰老迟缓,代谢强度降低缓慢,过氧化程度低,其他处理较276 kg/hm2处理叶绿素含量及衰老指标等均有所下降。【结论】适量施氮(276kg/hm2)可提高冬小麦旗叶叶绿素和可溶性蛋白质含量及SOD和CAT活性、降低膜脂过氧化程度,过量施氮(345kg/hm2)反而促进了冬小麦旗叶的衰老。更多还原

【Abstract】 【Objective】The study was to promulgate the aging changes of Winter wheat flag leaves and oxygen metabolism under nitrogen provision.【Method】The experiment investigated the chlorophyll contents,photosynthetic rates,MDA content,SOD and POD activities and solvable protein content in the flag leaves of winter wheat at different rates of nitrogen provision(0,138,276 and 345 kg/hm2).【Result】Each time after flowering,the chlorophyll contents of the flag leaf were the highest,leaf senescence was postponed,metabolism intensity reduced slowly and the peroxidation degree was low when the amount of the nitrogen-provision was 276 kg/hm2.The chlorophyll content and the senile target and so on were not as good as the treatments in which the nitrogen-provision was 0,138,345 kg/hm2.【Conclusion】Right amount of nitrogen provision(276 kg/hm2) raises the chlorophyll content,the soluble protein content,the SOD and CAT activities,reduces the peroxidation degree of the membrane fat,and over nitrogen-provision(345 kg/hm2) promotes the leaf senescence of winter wheat.更多还原