Identification of genetic factors contributing to heterosis in a hybrid from two elite maize inbred lines using molecular markers.
Identification of genetic factors contributing to heterosis in a hybrid from two elite maize inbred lines using molecular markers.
复制标题
使用分子标记鉴定导致两个优良玉米自交系杂种优势的遗传因素。
DOI：
10.1093/genetics/132.3.823
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发表时间：
1992
期刊：
影响因子：
3.3
通讯作者：
Lander,ES
中科院分区：
文献类型：
--
作者：
Stuber,CW;Lincoln,SE;Wolff,DW;Helentjaris,T;Lander,ES
利用分子标记识别影响重要农艺性状的数量性状基因座(QTL)已成为植物遗传学研究中的一条重要途径--无论是为了理解这些性状的遗传基础，还是为了设计新的植物改良方案。为了探索玉米遗传中的两个重要现象--杂种优势(杂种优势)和品种与环境互作(G×E)，本研究对B73和Mo17这两个广泛应用的玉米优良自交系的7个主要性状(包括籽粒产量)进行了QTL定位和表型效应分析。我们还比较了两种QTL的分析方法，传统的单标记方法和最近描述的区间作图方法。对三个州种植的3168块地(近10万株)进行了表型评估。利用代表玉米基因组90%-95%的76个标记，两种分析方法在整个基因组中检测到影响籽粒产量的QTL的结果几乎相同，但在6号染色体上检测到的其他数量性状的QTL较少。无论何时检测到控制产量的QTL，杂合子的表型都高于各自的纯合子(只有一个例外)，这不仅表明超显性(或伪超显性)，而且这些检测到的QTL在杂种优势中发挥着重要作用。这一结论得到了籽粒产量与杂合标记比例的高度相关的支持。虽然植物材料是在六个不同的环境中(北卡罗来纳州、爱荷华州和伊利诺伊州)种植和测量的，但几乎没有证据表明大多数QTL存在G×E互作。
The use of molecular markers to identify quantitative trait loci (QTLs) affecting agriculturally important traits has become a key approach in plant genetics-both for understanding the genetic basis of these traits and to help design novel plant improvement programs. In the study reported here, we mapped QTLs (and evaluated their phenotypic effects) associated with seven major traits (including grain yield) in a cross between two widely used elite maize inbred lines, B73 and Mo17, in order to explore two important phenomena in maize genetics-heterosis (hybrid vigor) and genotype-by-environment (G x E) interaction. We also compared two analytical approaches for identifying QTLs, the traditional single-marker method and the more recently described interval-mapping method. Phenotypic evaluations were made on 3168 plots (nearly 100,000 plants) grown in three states. Using 76 markers that represented 90-95% of the maize genome, both analytical methods showed virtually the same results in detecting QTLs affecting grain yield throughout the genome, except on chromosome 6. Fewer QTLs were detected for other quantitative traits measured. Whenever a QTL for grain yield was detected, the heterozygote had a higher phenotype than the respective homozygote (with only one exception) suggesting not only overdominance (or pseudooverdominance) but also that these detected QTLs play a significant role in heterosis. This conclusion was reinforced by a high correlation between grain yield and proportion of heterozygous markers. Although plant materials were grown and measured in six diverse environments (North Carolina, Iowa and Illinois) there was little evidence for G x E interaction for most QTLs.