玉米叶宽的遗传效应分析

Analysis of the Genetic Effects of Leaf Width in Maize

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。

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-earleaf 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.