Nilsen Kirby T, N'Diaye Amidou, MacLachlan P R, Clarke John M, Ruan Yuefeng, Cuthbert Richard D, Knox Ron E, Wiebe Krystalee, Cory Aron T, Walkowiak Sean, Beres Brian L, Graf Robert J, Clarke Fran R, Sharpe Andrew G, Distelfeld Assaf, Pozniak Curtis J
Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, Canada.
Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, SK, Canada.
PLoS One. 2017 Apr 11;12(4):e0175285. doi: 10.1371/journal.pone.0175285. eCollection 2017.
Breeding for solid-stemmed durum (Triticum turgidum L. var durum) and common wheat (Triticum aestivum L.) cultivars is one strategy to minimize yield losses caused by the wheat stem sawfly (Cephus cinctus Norton). Major stem-solidness QTL have been localized to the long arm of chromosome 3B in both wheat species, but it is unclear if these QTL span a common genetic interval. In this study, we have improved the resolution of the QTL on chromosome 3B in a durum (Kofa/W9262-260D3) and common wheat (Lillian/Vesper) mapping population. Coincident QTL (LOD = 94-127, R2 = 78-92%) were localized near the telomere of chromosome 3BL in both mapping populations, which we designate SSt1. We further examined the SSt1 interval by using available consensus maps for durum and common wheat and compared genetic to physical intervals by anchoring markers to the current version of the wild emmer wheat (WEW) reference sequence. These results suggest that the SSt1 interval spans a physical distance of 1.6 Mb in WEW (positions 833.4-835.0 Mb). In addition, minor QTL were identified on chromosomes 2A, 2D, 4A, and 5A that were found to synergistically enhance expression of SSt1 to increase stem-solidness. These results suggest that developing new wheat cultivars with improved stem-solidness is possible by combining SSt1 with favorable alleles at minor loci within both wheat species.
培育茎杆坚实的硬粒小麦（Triticum turgidum L. var durum）和普通小麦（Triticum aestivum L.）品种是将小麦茎蜂（Cephus cinctus Norton）造成的产量损失降至最低的一种策略。在这两个小麦品种中，主要的茎杆坚实度QTL已定位到3B染色体的长臂上，但尚不清楚这些QTL是否跨越一个共同的遗传区间。在本研究中，我们提高了硬粒小麦（Kofa/W9262 - 260D3）和普通小麦（Lillian/Vesper）作图群体中3B染色体上QTL的分辨率。在两个作图群体中，重合的QTL（LOD = 94 - 127，R2 = 78 - 92%）定位在3BL染色体的端粒附近，我们将其命名为SSt1。我们通过使用现有的硬粒小麦和普通小麦的共识图谱进一步研究了SSt1区间，并通过将标记锚定到野生二粒小麦（WEW）参考序列的当前版本，比较了遗传区间和物理区间。这些结果表明，SSt1区间在WEW中跨越1.6 Mb的物理距离（位置833.4 - 835.0 Mb）。此外，在2A、2D、4A和5A染色体上鉴定出了次要QTL，发现它们能协同增强SSt1的表达以提高茎杆坚实度。这些结果表明，通过在两个小麦品种中，将SSt1与次要位点的有利等位基因相结合，有可能培育出茎杆坚实度更高的新小麦品种。
