玉米胚乳突变基因ae1和du1的遗传效应

Genetic Effects of Mutation ae1 and du1 in Maize

利用玉米ae1和du1隐性纯和突变自交系与普通玉米自交系48-2的杂交F1、F2代子粒为研究材料,通过单粒法测定子粒的直链淀粉含量和重量,用于分析玉米胚乳突变基因ae1和du1的遗传效应。结果表明:F2代中具有ae1或者du1纯和突变的子粒表皮皱缩,重量明显下降,直链淀粉含量显著提高。在ae1与du1的杂交后代中,子粒的单粒重和直链淀粉含量没有显著变化,表明ae1与du1双突变并不能导致直链淀粉含量增加。单突变的ae1和du1群体内各子粒间的直链淀粉含量和重量差异较大,说明遗传背景中存在影响直链淀粉含量的修饰基因,表明在选育高直链淀粉玉米品系时,应当重视遗传背景的选择和修饰基因的累加。采用单粒法技术对分离后代进行直链淀粉含量和重量选择,有利于积累高直链淀粉修饰基因,是选育子粒饱满、高粒重的高直链淀粉玉米自交系的有效方法。

To study the genetic effects of mutation ae 1 and dul in maize ,the F1 and F2 seeds of the cross of conventional corn inbred line 48-2/ae1 maize recessive mutant and the cross of inbred line 48-2/du1 maize recessive mutant were used as the materials to assay the amylose content as well as weight of single seed. The result showed that the seeds possessing the ae 1 or dul allele were associated with remarkable increased amounts of amylose and decreased amounts of single seed weight. Nevertheless, the double-mutant maize （ae 1/du1） did not show great difference in amylose content indicating that double mutation does not necessarily lead to the sharp increase of amylose content. The amylose content and weight of single seed within each of the mutant population of ae 1 or du1 vary significantly highlighting the importance of genetic background in maize breeding. In this assay, the amylose content and weight of single seed in each population were measured respectively which could facilitate the accumulation of the modifying genes in the process of amylose synthesis. This method may serve as a practical technology to select the high amylose maize inbred line with the single seed method in breeding program.