不同基因型水稻抽穗后衰老进程的比较研究

A Comparative Study on the Senescence of Different Rice Genotype after Heading

本实验对汕优63、J85、老来青等三种不同基因型水稻品种衰老过程中的生理生化指标进行了分析。结果表明,随着叶片衰老进程,剑叶中的叶绿素含量逐渐下降,丙二醛含量逐渐上升,而根系活力在抽穗后一直呈下降趋势。进一步比较三种不同类型水稻叶片的衰老进程,发现:(1)在外界环境一致的情况下,三种水稻在这三个指标上变化明显不同,其中粳稻老来青抗衰老程度最高,而最易衰老的是杂交稻汕优63;(2)汕优63在抽穗后5～10d内衰老最为迅速;(3)根系活力的下降早于叶片中与衰老有关的指标变化。这表明在衰老过程中,根系的衰老先于叶片。

Some senescence-associated indexes in physiology and biochemistry of three rice genotype,Shangyou63,J85and Laolaiqing are studied in this experiment.The results showed that chlorophyll contents and root activity all decrease,while the malondialdehyd(MDA)contents increase during senescence.These senescence-associated indexes of three rice genotype are compared in the present study and we find that Laolaiqing keep highest chlorophyll contents and root activity after heading,while Shangyou63has lowest.However,the former shows lowest MDA contents and latter highest.Moreover,these indexes in Shangyou63change very rapidly5～10day after heading.We also find that the root activity is more sensitive than chlorophyll and MDA contents.It indicates that the senescence of roots is earlier than leaves.