5种重要农艺性状基因在水稻重组自交系群体中的定位

Mapping Five Agronomic Character Loci of Rice Based on a Recombinant Inbred Line Population

通过抗病虫害水稻品系"B5"与籼稻品种"明恢63"为亲本进行杂交,得到一个187个F8代的重组自交系群体.利用重组自交系群体构建的分子连锁图,对水稻抽穗期、株高、穗长、剑叶长和剑叶宽的性状进行了QTL分析,分别检测到影响抽穗期、株高、穗长、剑叶长和剑叶宽的农艺性状2、2、4、4、4个QTLs,并分别解释各表型性状总变异的50.6%、74.9%、34.1%、47.3%和46.2%.其中,控制抽穗期的Hd 6基因,控制株高的Ph 7基因和控制剑叶长的Fll 2b基因分别是效应值较大的主效座位,其余的为微效基因座位.相关性状的QTLs大多聚集在染色体的相近或相同区间,表现出成簇分布的现象.这些重要农艺性状的分析,可以为水稻分子标记辅助选择育种提供有用的遗传信息.

A mapping population of 187 recombinant inbred lines (RILs), which were developed through successive selfing up to 8 generations from a cross between rice line 'B5', resistant to disease and insect pests, and 'Minghui 63', a cultivar widely used as restorer line of hybrid rice. Analysis of quantitative trait loci (QTLs) was carried out based on the molecular linkage map constructed from the RIL population. Different QTLs were identified for heading date, plant height, panicle length, flag leaf length, and flag leaf width. They collectedly explained 50.6%、74.9%、34.1%、47.3% and 46.2% of phenotypic variations for these traits. Of the mapped QTLs, gene Hd-6,Ph-7 and Fll\|b2 controlling heading date, plant height and flag leaf length were major loci located on chromosome 6, 7 and 2, respectively. QTLs controlling the related agronomic traits were often mapped on the same or adjacent intervals, forming several clusters in rice chromosomes. The important agronomic trait loci were identified and analyzed can provide useful genetic information, which is used as molecular marker-aided selection in breeding program of B5.