Opaque2基因对糯玉米子粒品质的影响分析

玉米Opaque2(O2)基因突变显著影响子粒胚乳中蛋白体形成、淀粉含量、氨基酸组成等,其中,赖氨酸含量提高使营养品质大幅度提升。通过回交转育的方法构建17份糯玉米o2近等基因系,对子粒表型、种皮厚度、百粒重和粗淀粉含量等性状分析。结果表明,与对照相比,16个近等基因系子粒明显皱缩、胚乳变为粉质,6个近等基因系种皮厚度增加,11个近等基因系百粒重显著降低,12个近等基因系子粒粗淀粉含量显著降低。由此表明,o2基因的导入对糯玉米子粒表型、产量、淀粉含量等主要起负调控作用,影响程度与导入背景密切相关。

Effect of Opaque2 on the Quality of Waxy Corn Kernels

The mutation of Opaque2(O2) significantly affects protein body formation, starch content, and amino acid composition in the endosperm of corn kernels, and the increasing of lysine content significantly improves nutrition quality. Through the backcrossing scheme, near isogenic lines of 17 waxy corn backgrounds were constructed with the o2 mutation gene. By analyzing the traits of the kernel, including appearance, pericarp thickness, 100-kernel weight, and crude starch content, it showed that the kernels of 16 near isogenic lines were shrunken significantly and their endosperm changed to opaque obviously compared to the controls. Pericarp thickness of 6 lines increased, and the 100-kernal weight of 11 lines decreased significantly, crude starch content of 12 lines decreased significantly. It indicated that the introduction of o2 mutant gene mainly had a negative effect on kernel appearance, yield and crude starch content with waxy corn, but the degree of influence is related to corn background.