Genetic Dissection of Flowering Time in Wheat by High-density Genome-wide Association Mapping

小麦(Triticum aestivum L.)在全世界范围内种植，是人类最重要的营养作物之一。一粒粒小麦(Triticum Monoccum)是面包小麦的二倍体近缘种，具有共同的A染色体组。开花时间对植物适应不同环境的生命周期具有重要意义。QTL定位研究表明，谷类作物开花时间是一个复杂的性状，受春化、光周期和早熟性三条不同途径控制。在小麦中，由于高密度分子标记芯片的可用，高分辨率的全基因组关联图谱现在是可能的。该项目的主要目标是利用基于新型高密度SNP阵列的全基因组关联作图方法来研究小麦开花时间的调控。具体地说，该项目的目的是(1)研究面包小麦和一粒粒小麦开花时间在多地点田间试验中对环境线索的表型变异，(2)用候选3基因方法研究PPD等位基因对开花时间的影响，(3)在高密度全基因组关联作图中确定开花时间的遗传结构，(4)通过面包小麦和一角小麦的比较来研究小麦开花时间遗传结构的可塑性。

Wheat (Triticum aestivum L.) is grown worldwide and is one of the most important crops for human nutrition. Einkorn wheat (Triticum monococcum) is a diploid relative of bread wheat and both have the A genome in common. The timing of flowering is of major importance for plants to optimally adjust their life cycle to diverse environments. QTL mapping studies indicated that flowering time in cereals is a complex trait, which is controlled by three different pathways: vernalization, photoperiod and earliness per se. In wheat, high-resolution genome-wide association mapping is now possible, because of the availability of a high density molecular marker chip. The main goal of the proposed project is to investigate the regulation of flowering time in wheat using a genome-wide association mapping approach based on a novel high-density SNP array. In particular, the project aims to (1) investigate the phenotypic variation of flowering time of bread wheat and Einkorn wheat in response to environmental cues in multilocation field trials, (2) study the effects of Ppd alleles on flowering time in a candidate 3 gene approach, (3) determine the genetic architecture of flowering time in a high-density genome-wide association mapping, and (4) investigate the plasticity of the genetic architecture of flowering time in wheat by a comparison between bread wheat and Einkorn wheat.