玉米产量相关性状的QTL定位与剖析

玉米因其自身具有高产潜质而成为了当今世界最重要的粮食作物之一.玉米产量是复杂的数量性状,由许多主/微效基因控制,易受各种环境因素影响.果穗是玉米的主要收获器官,籽粒性状是玉米品质的重要体现,因此发掘玉米穗部性状和籽粒性状相关QTL对玉米的遗传改良,培育优质高产的玉米具有重要意义.本研究白刺包谷(P2)和妻染黄(P13)为亲本构建了包含152个家系的F2∶3作图群体,选择在两亲本间具有多态性的176个微卫星标记构建遗传图谱,对产量相关性状进行了单环境的QTL定位与分析.最终定位到了14个QTL,分布在除9号染色体外的其余9条染色体上,单个QTL可解释的表型变异率为4.9％～18.8％.值得注意的是,在6号染色体上的百粒重和穗行数的一致性QTL(qHKW06-1和qERN06-1)与8号染色体上的穗行数QTL(qERN08-1)是本研究中特有的,其中qERN08-1解释了12.4％的表型变异率.

Detection of Quantitative Trait Loci for Maize Grain Yield and Kernel-related Traits

Maize(Zea mays L.) is one of the most important cereal crops and playing an increasingly vital role,owing to its high yield potential.As a complex quantitative trait,grain yield are controlled by many quantitative trait loci(QTLs) and influenced by kinds of environmental factors.Maize ear is the main harvested organ and kernel is an important indication of grain quality.Therefore,the QTLs detection of ear and kernel traits is very important in maize breeding.In the study,a F2∶3 mapping population consisting of 152 lines was constructed,which was derived from a cross between the parents Baicibaogu(P2) and Qiranhuang(P13).176 polymorphic simple repeat sequence markers were used to explore QTL for ear row number(ERN),kernel number per row(RKN),and 100-kernel weight(HKW).A total of 14 QTLs detected were distributed on 9 chromosomes except chromosome 9.Single QTL accounted for the phenotypic variance ranged from 4.9％ to 18.8％.Notably,a QTL cluster simultaneously controlled HKW and ERN on chromosome 6 and a QTL(qERN08-1) for ERN on chromosome 8 were specific to the population,among which qERN08-1 explained 12.4％ of the phenotypic variance.