Mapping QTLs for grain dormancy on wheat chromosome 3A and the group 4 chromosomes, and their combined effect
Mapping QTLs for grain dormancy on wheat chromosome 3A and the group 4 chromosomes, and their combined effect
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DOI：
10.1007/s00122-005-1972-1
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发表时间：
2005-05-01
影响因子：
5.4
通讯作者：
Miura, H
中科院分区：
文献类型：
--
作者：
Mori, M;Uchino, N;Miura, H
在受控环境下进行的研究中，鉴定了来自高度休眠小麦Zenkoujikomugi（Zen）的籽粒休眠性的主效QTL QPhs.ocs-3A.1。需要进一步的研究来剖析QPhs.ocs-3A.1在不同田间条件下的精确位置和表达，因为检测籽粒休眠性状遗传位点的能力受到环境效应和基因型/环境互作的影响。第4组染色体也被证明是可能的QTL位点的种子休眠。本研究的目的是（1）在QPhs.ocs-3A.1区域定位额外的分子标记，（2）鉴定第4组染色体上的QTL，（3）阐明它们的联合效应。我们研究了重组自交系（RILs）从中国春（CS）和禅之间的交叉在一个位置超过3年的时间和1年在不同的位置。在间隔定位研究中，QPhs.ocs-3A.1被定位在染色体3A短臂近端Xbarc 310和Xbcd 907侧翼的4.6 cM区域内。qPhs.ocs-3A.1被证实是主要的休眠QTL，因为它解释了很大一部分（11.6-44.8%）的表型变异，并强烈显示在休眠打破条件下或在低发芽温度。对于在染色体4A长臂上鉴定的QPhs.ocs-4A.1和在Chr 4 B长臂的着丝粒区域上鉴定的QPhs.ocs-4B.1，试验之间的LOD峰位置和期望的等位基因是一致的，而LOD评分和对表型变异的贡献有所不同。在125个RIL中观察到了超亲分离体，其中大多数具有赋予较高休眠性的三个等位基因的组合：QPhs.ocs-3A.1和QPhs.ocs-4A.1的Zen等位基因和QPhs. ocs-4 B1的CS等位基因。这证明了所需等位基因对加速籽粒休眠的组合效应，其总效应上级于Zen。
A major QTL for grain dormancy, QPhs.ocs-3A.1, derived from the highly dormant wheat Zenkoujikomugi (Zen), has been identified in a study made under a controlled environment. Further investigations were needed to dissect the precise position and expression of QPhs.ocs-3A.1 under different field conditions because the ability to detect genetic loci for grain dormancy traits is compromised by environmental effects and genotype/environment interactions. Group 4 chromosomes have also been shown to be possible sites of QTLs for grain dormancy. The objectives of this study were (1) to locate additional molecular markers in the QPhs.ocs-3A.1 region, (2) to identify QTLs on the group 4 chromosomes and (3) to elucidate their combined effects. We examined the recombinant inbred lines (RILs) from a cross between Chinese Spring (CS) and Zen over a 3-year period in one location and 1 year in a different location. In an interval mapping study QPhs.ocs-3A.1 was mapped to within the 4.6 cM region flanked by Xbarc310 and Xbcd907 at the proximal end of the short arm of chromosome 3A. QPhs.ocs-3A.1 was confirmed to be the predominant dormancy QTL since it explained a large portion (11.6-44.8%) of the phenotypic variation, and was strongly displayed under dormancy-breaking conditions or at low germination temperatures. For QPhs.ocs-4A.1, identified on the long arm of chromosome 4A, and QPhs.ocs-4B.1, on the centromeric region of the long arm of Chr 4B, the LOD peak positions and the desirable allele were consistent between the trials, while the LOD scores and contribution to the phenotypic variation varied. Transgressive segregants were observed among the 125 RILs and most of them had a combination of the three alleles conferring a higher dormancy: the Zen alleles at QPhs.ocs-3A.1 and QPhs.ocs-4A.1 and the CS allele at QPhs.ocs-4B1. This demonstrated a combined effect of the desirable alleles on accelerating grain dormancy, with their total effect being superior to that of Zen.