小麦突变体返白系返白机理的研究——Ⅱ、返白阶段叶绿素代谢变化研究

Studies on the Albrescent Mechanism in Mutant "Stage Albinism Line of Winter Wheat" I.Changes in the Chlorophyll Metabolism During the Albescent Stage

与对照矮变1号相比,返白过程中返白系叶片内叶绿素(Chl)和类胡萝卜素(Caro)含量降低,复绿过程中,两种色素的含量都升高,但在整个返白阶段中,返白系Chl/Caro比值始终低于对照矮变1号,说明类胡萝卜素含量的降低不是造成叶片变白的原因。对叶绿素生物合成中的两个关键中间产物δ-氨基乙酰丙酸(ALA)和原叶绿素(酸酯)[Pchl(ide)]的分析发现,在返白过程中,ALA相对积累,而Pchl(ide)含量降低,推测在返白过程中叶绿素合成受阻。

Compared with 'Aibian No.l' ,the content of Chi (chlorophyll) and Caro (carotinoid) in the leaves of albinism line decreased in the albescent process, but increased in the regreening process. And the ratio between Ch1/ Caro in the mutant leaves was always lower than that in the control--Aibian No.lv during the albescent stage, thus, indicating that the decrease in the con-ent of Caro is not the main reason to cause the leaves become white or albescent, t has been found through an analysis of the content of ALA(δ-aminole-vulinic acid) and Pchl (ide) (protochlorophyll (ide) ) two precursors of the biosynthesis of Chi. that the content of ALA relatively accumulated, but that of Pchl (ide) decreased during the albescent process. Thus, it can be deduced that the biosynthesis of Chi was blocked in the albescent process. This might be one reason that the leaf color of the albinism line of winter wheat can turn from green to white in the albescent process.