玉米叶宽的遗传效应分析

叶片是玉米植株进行光合作用最主要的器官,对玉米产量贡献巨大。利用1份玉米穗三叶窄叶和2份穗三叶宽叶自交系为材料,构建2套6世代分离群体（群体1和群体2）,利用经典植物数量性状混合遗传模型主基因+多基因多世代联合分析方法,对玉米穗三叶叶片宽度的遗传效应进行分析。结果表明,2套群体穗三叶叶宽遗传均受不同的基因数量控制,属于不同的多基因遗传模型。在群体1中,穗上叶叶宽符合1对加性-显性主基因+加性-显性-上位性多基因模型（D-0）,穗位叶叶宽符合2对基因加性-显性-上位性模型（B-1）,穗下叶叶宽符合2对基因加性-显性模型（B-2）。在群体2中,穗上叶叶宽符合2对加性主基因+加性-显性多基因模型（E-3）,穗位叶和穗下叶叶宽符合1对加性主基因+加性-显性多基因模型（D-2）。综上可知,玉米叶宽主要受主效基因控制,且在不同的遗传背景下,玉米穗三叶的遗传模式存在差异,穗位叶、穗上叶及穗下叶的遗传模式均受遗传背景的影响。

Analysis of the Genetic Effects of Leaf Width in Maize

Leaf is the most crucial component of plant photosynthesis, and it can significantly increase maize yield. In order to create two sets of six-generation segregating populations, one three-ear-leaf narrow-leaf inbred line and two three-ear-leaf wide-leaf inbred lines were crossed and backcrossed, respectively (population 1 and population 2). The genetic influence of the leaf width of the three-ear-leaf of maize on the cob was analysed using the main gene and multi-gene multi-generation combination analysis method of the mixed genetic model of plant quantitative traits. The results showed that the inheritance of the leaf width of the two groups of three-ear-leaf was controlled by different gene numbers and belonged to different polygenic genetic models. In population 1, the width of leaf above ear conformed to a pair of additive-dominant major gene+additive-dominant-epistatic polygene model (D-0), and the width of ear-leaf conformed to the two pairs of gene additive-dominant-epistatic model (B-1), the width of leaf under ear conformed to the two-pair gene additive-dominant model (B-2). In population 2, the width of leaf above ear conformed to the two pairs of additive major genes+ additive-dominant polygene model (E-3), and the widths of ear-leaf and under ear conformed to a pair of additive major genes+additive-dominant polygene model (D-2). Therefore, we speculate that maize leaf width was mainly controlled by the main effect genes, and the genetic pattern of the three-ear-leaf of maize was different under different genetic backgrounds. The genetic patterns of ear-leaf, leaf above ear and leaf under ear were all affected on major gene control.