摘要： 以玉米品种豫单2002和郑单958为材料，研究不同基因型玉米叶片衰老与活性氧代谢的关系及其化学调控。结果表明:两品种4个叶位叶片的可溶性蛋白含量、SOD、CAT活性呈由高到低的变化趋势(第5叶位除外)，但MDA含量随着叶片的衰老而升高。与豫单2002相比，郑单958各叶位叶片衰老过程中SOD、CAT活性下降较慢，叶片功能期持续时间长，生育后期仍能保持相对较高的可溶性蛋白含量，籽粒产量显著高于豫单2002。经拌种处理能提高各个叶位叶片SOD、CAT含量，降低可溶性蛋白降解速率及MDA积累速率。综合分析表明，拌种处理能有效控制或延缓叶片的衰老进程，维持叶片生理功能，提高玉米产量。

关键词: 玉米叶片, 衰老, 保护酶, 植物生长调节剂

Abstract: This research aims to study maize leaves activity and the senescence characteristics of oxygen metabo-lism and it regulation by using Zhengdan 958 and Yudan 2002. The results showed that SOD，CAT activi ties of differ-entleaves rose and then declined with plant senescence，but MDA contents gradually increased as leaves senescencewent on. Although the leaves of the two varieties generally presented a similar tendency in their senescence，their se-nescence progresses significantly differed. Compared with leaves of Yudan 2002，the content of active oxygen protectiveenzyme and soluble protein of Zhengdan 958 were higher and declined more slowly and the content of MDA was lowerand rose more gradually. The activities of SOD and CAT of leaves increased in the seed dressing treatments which re-sulted in decreased MDA contents and soluble protein degradation rate of leaves. Results suggested that the treatmentsof maize seed dressing can prolong leaf life，effectively control or slow down the senescence，maintain physiolo gicalfunctions of its leaves during the growth and increase yield.

Key words: Maize leaf, Senescence, Defending enzyme activity, Plant growth regulator

中图分类号: 

• S513.01