The Vrn-H2 locus is a major determinant of flowering time in a facultative x winter growth habit barley (Hordeum vulgare L.) mapping population
The Vrn-H2 locus is a major determinant of flowering time in a facultative x winter growth habit barley (Hordeum vulgare L.) mapping population
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DOI：
10.1007/s00122-005-1979-7
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发表时间：
2005-05-01
影响因子：
5.4
通讯作者：
Bedo, Z
中科院分区：
文献类型：
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作者：
Karsai, I;Szucs, P;Bedo, Z
以解剖开花时间，春化反应，光周期敏感性的遗传决定因素的目的，我们定位的候选基因Vrn-H2和Vrn-H1在兼性×冬大麦作图群体，并确定其与开花时间和春化通过QTL分析的关系。Vrn-H2候选ZCCT-H基因从兼性亲本中完全缺失，并且存在于冬大麦亲本中。该基因是主要的决定因素，开花时间长光周期控制环境实验中，无论春化，春播田间试验。它是春化反应的唯一决定因子，但当春化要求得到满足时，缺失的效果受光周期的调节。在短光周期下没有影响。Vrn-H1候选基因（HvBM 5A）的基础上，我们确定在这个基因的启动子的微卫星多态性进行了定位。除此之外，双亲的HvBM 5A等位基因完全相同。因此，显着的开花时间QTL效应与该位点表明紧密连锁，而不是多效性。该QTL效应的大小小于与Vrn-H2位点相关的QTL效应，并且在与Vrn-H2的双向互作中是显著的。Vrn-H1位点对春化反应没有影响。我们的研究结果支持大麦春化反应的Vrn-H2/Vrn-H1阻遏物/结构基因模型，并表明光周期也可能影响Vrn基因或紧密连锁的位点。
With the aim of dissecting the genetic determinants of flowering time, vernalization response, and photoperiod sensitivity, we mapped the candidate genes for Vrn-H2 and Vrn-H1 in a facultative x winter barley mapping population and determined their relationships with flowering time and vernalization via QTL analysis. The Vrn-H2 candidate ZCCT-H genes were completely missing from the facultative parent and present in the winter barley parent. This gene was the major determinant of flowering time under long photoperiods in controlled environment experiments, irrespective of vernalization, and under spring-sown field experiments. It was the sole determinant of vernalization response, but the effect of the deletion was modulated by photoperiods when the vernalization requirement was fulfilled. There was no effect under short photoperiods. The Vrn-H1 candidate gene (HvBM5A) was mapped based on a microsatellite polymorphism we identified in the promoter of this gene. Otherwise, the HvBM5A alleles for the two parents were identical. Therefore, the significant flowering time QTL effect associated with this locus suggests tight linkage rather than pleiotropy. This QTL effect was smaller in magnitude than those associated with the Vrn-H2 locus and was significant in two-way interactions with Vrn-H2. The Vrn-H1 locus had no effect on vernalization response. Our results support the Vrn-H2/Vrn-H1 repressor/structural gene model for vernalization response in barley and suggest that photoperiod may also affect the Vrn genes or tightly linked loci.