摘要
本文追踪了稻叶衰老过程中叶片光合作用，Ｒｕｂｉｓｃｏ初始羧化活力，总羧化活力及含量，可溶性蛋白和叶绿素含量的变化，以明确哪一个是叶片衰老期间光合衰退的主要原因．结果表明，尽管光合速率与上述因子都有极显著的直线正相关，但其相关系数依次降低，净光合速率与Ｒｕｂｉｓｃｏ初始羧化活力，Ｒｕｂｉｓｃｏ总羧化活力，Ｒｕｂｉｓｃｏ含量，可溶性蛋白和叶绿素含量的决定系数（ｒ￣２）分别为０．９１，０．９０，０．７８，０．７３和０．７１．在净光合速率与Ｒｕｂｉｓｃｏ初始羧化活力之间不仅有最高的决定系数，而且无论第１０叶还是剑叶的数据都较合理地分布在回归线两侧，这表明稻叶衰老期间Ｒｕｂｉｓｃｏ初始羧化活力下降是光合衰退的最直接的内在因素．
The changes in photosynthetic rate(Pn),initial and total activities of Rubisco car-boxylation and contents of Rubisco,soluble protein and chorophyll were traced in the process ofleaf senescence in rice grown outside so as to clarify what is predominantly responsible for the de-cline in Pn during leaf senescence. The regression cofficients reduced in order between Pn andthose factors although there existed an extremely significantly positive correlation between Pn andeach of them. It can be suggested,from that there is the highest regression coefficient between Pnand initial Rubisco activity and the most suitable distribution of the data into both sides of regres-sion line,irrespective of the 10th leaf or flag leaf, that initial activity of Rubisco carboxylation is amore direct factors for the declination of photosynthesis in process of leaf senescence in rice plant.
关键词
水稻
叶片衰老
光合作用
可溶性蛋白
叶绿素
rice leaf senescence
photosynthesis
Rubisco
soluble protein
chlorophyll
