摘要
常规育种中出现的偶然变异植株,用来作光合机理和遗传机理的研究,不需要复杂的生物技术操作手段,受到很多学者关注。植物的花斑叶是一种结构上的嵌合体。Hayden和Hopkins发现玉米(zae mays L.)的黄绿色突变体OYyg中缺少介于CPⅠ与CPⅡ之间的一条被他们称为复合体Ⅳ的小带。李玉湘和李继耕用玉米白色叶片和条纹叶片两种突变系,进行叶绿素蛋白复合体研究表明,纯白色突变系叶片中捕光叶绿素a/b蛋白复合体的合成受阻。本文用zb/zb与一正常自交系杂交,得到的F_1代为zb/zb基因型。将其分别播种后,对白色叶片和绿色叶片叶绿体膜的光合特性进行了多项比较研究。
Crossed the zb/zb with the normal maize, Zea mays L. , the F1 was zb/zb genotype. The development of thylakoid membranes of the albino maize (zb/zb) was inhibited at its initial stage. The content of Chl-protein complexes decreased evidently. The absorption of light energy was only 43 % and the potential activity of PSⅡ was 18.5% in the albino maize chloroplasts as compared with the normal maize. The conversion efficiency of primary light energy of PS Ⅱ of the albino chloroplasts was 36.1% of the normal. The fluorescence intensity at 77 K in the albino maize chloroplasts was declined. These results proved that the constructive process of thylakoid lamellae was disturbed by the albino gene zb/zb. The Chl-protein complexes and the grana lamella, in the incomplete membrane of the albino maize were deficient, although its PS Ⅰ developed completely. It can be deduced that the potential activity and the conversion efficiency of the primary light energy of PS Ⅱ in the albino maize was lower than those in the control, perhaps, it is due to the incomplete development of the Chl-protein complexes and the electron transport chains.
关键词
玉米
突变体
叶绿体
光合特性
Maize mutant, Chloroplast, Activity of PS II , Conversion efficiency of primary light energy of PS Ⅱ , Excitation energy distribution
