Positional cloning of flowering time QTLs conferring adaptability to wide cultivation area in Japanese rice cultivars.

水稻品种的开花时间多样化，以适应各地种植地区的生长季节。数量性状位点（QTL）分析表明，两个QTL （Hd16和Hd17）参与了粳稻品种“光”和“日本裸”的开花时间差异。基因组区域的高分辨率定位和序列分析使我们能够专注于每个QTL的候选基因。与对照相比，含有Hd16候选基因片段的转基因植株在短日照和长日照条件下开花时间发生了变化。Hd16基因与Hd2基因之间存在显著的基因互作作用，而Hd2基因此前已被确定为水稻开花时间QTL。

Flowering time of rice cultivars has diversified to adjust to the growing season in each local cultivation area. Quantitative trait locus (QTL) analysis revealed that two QTLs (Hd16 and Hd17) were involved in the difference of flowering time between the rice japonica cultivars Koshihikari and Nipponbare. High-resolution mapping and sequence analysis of the genomic regions enabled us to focus on candidate genes for each QTL. Compared to control lines, flowering time in transgenic plants with a genomic fragment containing the Hd16 candidate gene was changed under short and long day-length conditions. Significant digenic interaction of Hd16 was observed with Hd2, which was previously identified as a flowering time QTL in rice.