大穗型水稻穗部性状的QTL定位

QTL analysis of panicle traits in large panicle rice

【目的】对大穗型水稻穗部性状的数量性状基因座（QTL）进行定位,为水稻超高产育种提供优质的种质材料。【方法】利用95个在双亲具有明显多态性的分子标记和213个由大穗型水稻材料1p1与9311构建的F2群体单株,采用完备区间加性模型作图法（ICIM-ADD）对穗长、每穗粒数和着粒密度3个穗部性状的QTL进行检测。【结果】共检测到5个穗部性状QTL,其中穗长QTL 1个,每穗粒数QTL 2个,着粒密度QTL 2个,分布于第3、4、6、10和11号染色体上。检测到的QTL LOD介于2.63-2.91,表型贡献率为7.42%-17.72%,贡献率大于10.00%的主效QTL有2个（qSSD-3-1和qPL-11-1）,分别有2个和3个QTL的增效等位基因来源于大穗1p1和9311。【结论】定位得到的主效QTL qSDD-3-1和qPL-11-1可用于分子标记辅助选择育种,新的穗长QTL qPL-11-1可用于精细定位和克隆。

[Objective]The present study was conducted to locate QTLs of panicle traits in large panicle rice, in order to provide high-quality germplasm resources in breeding programs of super high-yield rice. [Method]A F2 population in-cluding 213 plants derived from hybrid of large panicle materials lp1 and 9311, and 95 molecular markers which had ob-vious polymorphism in bi-parents were used. Then inclusive composite interval mapping（ICIM） method were utilized to detect QTLs of panicle length（PL）, spikelet number per panicle（SPP）, and seed setting density（SSD） in this population.[Result]A total of 5 related QTLs were detected on chromosome 3, 4, 6, 10 and 11, including 1 QTLs for PL, 2 Ma-jor QTLs for SPP and 2 QTLs for SSD. The LOD scores of QTLs ranged from 2.63 to 2.91, and the phenotypic variation explained（PVE） ranged from 7.42% to 17.72%, and there were 2 QTLs（qSSD-3-1 and qPL-11-1） whose PVE were more than 10.00%. 2 QTLs and 3 QTLs source of positive allele were lp1 and 9311, respectively. [Conclusion]The detected qSSD-3-1 and qPL-11-1 are used in marker-assisted selection breeding, and qPL-11-1, which is one new QTL of PL, can be used in fine mapping and clone.