冬小麦旗叶大小及籽粒相关性状的QTL分析

Quantitative Trait Loci Analysis of Flag Leaf Size and Grain Relative Traits in Winter Wheat

为发掘控制小麦旗叶长、宽、面积和千粒质量、穗粒数、穗粒质量的QTL,并阐明旗叶大小与籽粒性状之间的遗传关系,以农大3338和京冬6号构建的包含216个家系的DH群体为材料,于2015年和2016年分别在临汾和运城进行了田间试验,结合含有469个标记的遗传图谱,利用复合区间作图法进行了QTL分析。结果显示,共检测到105个加性QTL,其中,40个为旗叶性状的QTL,65个为籽粒性状的QTL,单个QTL的贡献率为2. 28%～39. 91%。在1B、2A、2B、2D、3A、4A、4B、4D、6A、6D和7A染色体发现了多个QTL富集区,富集区内的QTL或紧密连锁,或一因多效,在QTL水平证实了旗叶长、宽、面积和千粒质量、穗粒质量、穗粒数是紧密关联的。7个QTL (Qflw-4A. 1、Qflw-4B. 1、Qflw-4D. 1、Qfla-4B、Qtgw-4A. 1、Qtgw-4B. 2、Qtgw-4B. 3)能够在3种或4种环境中被重复检测到,具有较高的LOD值,并对表型具有较高的贡献率。对这7个稳定表达的主效QTL进行深入挖掘与精细定位,可能对于MAS育种和基因克隆具有重要的意义。

To identify quantitative trait loci(QTL)for flag leaf length(FLL),width(FLW),area(FLA),thousand grain weight(TGW),grain number per spike(GNS),grain weight per spike(GWS)and understand the genetic relationship among those traits,we developed a doubled haploid(DH)population with 216 lines,derived from the cross between Nongda 3338 and Jingdong 6.The field experiments were carried out in Linfen and Yuncheng in 2015 and 2016,and QTL analysis was conducted by composite interval mapping method combining with genetic maps containing 469 markers.The results showed that a total of 105 additive QTLs were detected,forty of them were QTLs for flag leaf traits and sixty-five were for grain traits,with single QTL explaining 2.28%-39.91%of the phenotypic variances.Several QTLs were identified in the same region or adjacent regions on the 1B,2A,2B,2D,3A,4A,4B,4D,6A,6D and 7A chromosome,these QTLs were closely linked to each other or multi-effect,confirmed those phenotypic data were closely-related under QTL level.Seven QTLs(Qflw-4A.1,Qflw-4B.1,Qflw-4D.1,Qfla-4B,Qtgw-4A.1,Qtgw-4B.2,Qtgw-4B.3)had high LOD value were detected repeatedly under three or four environments.Those seven stable expression QTLs might have great significance for MAS breeding and gene cloning program.