利用双单倍体群体剖析水稻产量及其相关性状的遗传基础

主效QTL、上位性效应和它们与环境的互作(QE)都是数量性状的重要遗传因素。利用籼粳交珍汕97／武育粳2号F1植株上的花药进行组织培养得到的190个双单倍体群体和179个微卫星标记，通过两年两重复田间试验，采用混合线性模型方法分析了9个控制水稻产量及其相关性状的遗传效应，得到57个主效QTL，41对上位性互作，8对QTL与环境的互作和7对上位性效应与环境的互作。单个主效QTL解释这些性状1．3％～25．8％的表型方差。各性状QTL的累积表型贡献率达11．5％～66．8％。大多数性状之间具有显著的表型相关性，相关性较高的性状之间常具有较多共同或紧密连锁的QTL。结果表明，基因的多效性或紧密连锁可能是性状相关的重要遗传基础。

Characterization of the Genetic Basis for Yield and Its Component Traits of Rice Revealed by Doubled Haploid Population

Main-effect QTL,epistatic effects and their interactions with environment are important genetic components of quantitative traits.In this study,we analyzed the QTLs,epistatic effects and QTL by environment interactions (QE) underlying nine traits of yield and yield-component,using a doubled-haploid (DH) population consisted of 190 lines from the cross between an indica parent Zhenshan 97 and a japonica parent WYJ 2,and tested in two-year replicated field trials.A genetic linkage map with 179 SSR (simple sequence repeat) marker loci was constructed.A mixed linear model approach was applied to detect QTLs,digenic interactions and QEs for the nine traits.In total,57 QTLs of main effects,41 digenic interactions,eight QEs and seven interactions of epistasis by environment were detected.Each of the main-effect QTLs individually explained 1.3% to 25.8% of the phenotypic variations.And they collectively explained 11.5% to 66.8% of the phenotypic variations for these traits.Most of the traits (except seed setting) had the QTLs simultaneously detected in two years.Many of the traits shared same QTLs with each other,which is consistent with their significant phenotypic correlations.The pleiotropism or tight linkage of QTLs for different traits might be the important genetic base for trait correlations.The environmental influences on the stability of the trait performance were also discussed.