Validation of grain yield QTL from soft winter wheat using a CIMMYT spring wheat panel

Validation of quantitative trait loci (QTLs) is an essential step in marker-assisted breeding. The objectives of this study were to validate grain yield (GY) QTLs previously identified in soft red winter wheat (Triticum aestivum L.) through biparental and association mapping using the spring wheat association mapping initiative (WAMI) panel from CIMMYT, Mexico, and to identify allele combinations of the validated QTLs that resulted to the highest GY. Linked single-nucleotide polymorphisms for IWA3560 (3A), IWA1818 (4B), and IWA755 (6B) were significantly associated (P < 0.001) with GY, grain number, and thousand-grain weight in the WAMI. Lines possessing the favorable allele for the QTL at the 3A, 4B, and 6B loci (ACG allele combination) validated on the WAMI had the highest mean GY at 4.55 t ha−1, but three other haplotypes (ACA, GCA, and GCG) differing by one or two alleles in the validated QTL regions were not significantly different. These results validate GY QTLs across winter a...

数量性状位点（quantitative trait loci, QTLs）的验证是标记辅助育种中的关键步骤。本研究的目标为：利用来自墨西哥国际玉米小麦改良中心（CIMMYT）的春小麦关联作图倡议（WAMI）群体，通过双亲作图与关联作图，对此前在软红冬小麦（普通小麦Triticum aestivum L.）中鉴定出的籽粒产量（grain yield, GY）QTLs进行验证，并筛选出可带来最高籽粒产量的已验证QTL等位基因组合。在WAMI群体中，与IWA3560（3A染色体）、IWA1818（4B染色体）及IWA755（6B染色体）连锁的单核苷酸多态性位点，与籽粒产量、籽粒数及千粒重呈极显著关联（P < 0.001）。携带3A、4B及6B位点QTL有利等位基因的株系（ACG等位基因组合，已在WAMI群体中验证）的平均籽粒产量最高，达4.55吨/公顷；而另外3种在已验证QTL区域存在1个或2个等位基因差异的单倍型（ACA、GCA及GCG），其籽粒产量无显著差异。本研究结果验证了跨冬性...的籽粒产量QTLs。