不同品种谷子叶片衰老与活性氧代谢研究

Leaf senescence and activate oxygen metabolism of different foxtail millet varieties

【目的】揭示不同品种谷子叶片衰老及活性氧代谢的变化规律。【方法】以谷子品种‘05-61’和‘金谷3号’为材料,研究开花后至成熟期谷子叶片净光合速率(Pn)、叶绿素含量、酶促防御系统保护酶(SOD、CAT、POD)活性及MDA、H2O2和O2.-积累量的动态变化规律。【结果】2个参试品种各功能叶片的净光合速率(Pn)、叶绿素含量及SOD、CAT、POD活性均在开花14 d后逐渐下降,MDA、H2O2和O2.-含量随着叶片的衰老而升高;参试品种叶片衰老的总体变化趋势一致,但衰老进程存在显著差异;与‘金谷3号’相比,‘05-61’各功能叶片衰老过程中SOD、CAT、POD活性下降较慢,叶片功能期持续时间长,这在籽粒灌浆中后期表现尤为明显;‘05-61’籽粒产量显著高于‘金谷3号’。【结论】在谷子开花灌浆期间,有效控制或延缓开花叶片的衰老进程,维持叶片的生理功能,对籽粒产量的形成具有重要作用。

[Objective] This research aimed to study the leaves activity of different foxtail millet varieties and the aging characteristics of oxygen metabolism. [Method] The foxtail millet variations of the net photosynthetic rate （Pn）, the contents of chlorophyll, SOD, CAT and POD activities MDA, H2 02 and O2 contents of the leaves of two foxtail millet varieties, ＇05-61＇ and ＇Jingu 3＇ from flowering to maturing were studied. [Results] Results showed that the photosynthetic rate （Pn） and chlorophyll contents,SOD, CAT and POD activities gradually decreased from 14 days after the varieties flowered to maturing, but MDA, H20z and O2 contents gradually increased as leaves senescence went on. Although the leaves of the two varieties presented a similar tendency in their senescence,their senescence progresses significantly dif- fered. Compared with leaves of ＇Jingu 3＇ ,the leaves of ＇05-61＇declined slowly in SOD,CAT and POD ac- tivities, and these changes were observed significantly in the middle and late stage of grain filling. [Conclu- sion] The yield of ＇05-61＇ was significantly higher than that of ＇Jingu 3＇. It was important to seed yield formation of foxtail millet to effectively control or slow down the senescence of its leaves, and maintain physiological functions of its leaves during the later growth.