抽穗期是决定水稻品种适应地区和季节的关键性状。水稻抽穗期QTL对产量性状和（或）株高具多效作用是个普遍现象, 但是, 除了Ghd7和DTH8（Ghd8）, 其他水稻抽穗期基因的多效性尚需进一步验证。本研究针对抽穗期基因RFT1Hd3a所处区间和Hd1所处区间, 以珍汕97B为轮回亲本、密阳46为供体亲本, 构建了遗传背景基本一致的2个BC2F5分离群体；采用Windows QTL Cartographer 2.5进行抽穗期、株高及千粒重的QTL分析, 并根据RFT1Hd3a下游17 kb处的连锁标记Si2944及Hd1的基因标记Si9337的基因型, 将每个群体中的纯合基因型材料分成4组, 比较其表型差异。结果表明, 这2个区间对抽穗期、株高及千粒重均呈显著作用, 它们之间不呈显著互作, 且Hd1所处区间对3个性状的作用均强于RFT1Hd3a所处区间。
Heading date is a key factor determining the regional and seasonal adaptation of rice. It has been frequently observed that QTLs for heading date could exert pleiotropism on yield traits and plant height. However, the pleiotropism of QTLs for heading date other than Ghd7 and DTH8(Ghd8) remains to be validated. Two BC2F5 populations segregated in the regions harboring heading date gene RFT1Hd3a and Hd1 in an isogenic genetic background were constructed using Zhenshan 97B as the recurrent parent and Milyang 46 as the donor parent. QTLs for heading date, plant height and thousandgrain weight were detected using Windows QTL Cartographer 2.5. In addition, four homozygous combinations of RFT1Hd3a and Hd1 were classified based on the genotypes of Si2944 tightly linked to RFT1Hd3a and the Hd1 gene marker Si9337, and the phenotypic differences among the four groups were analyzed. QTLs were detected for each of the three traits analyzed in both regions, which did not interact with each other. It was also shown that the effects of the Hd1 region were always larger than that of the RFT1Hd3a region.
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