Nonoue Yasunori, Hori Kiyosumi, Ono Nozomi, Shibaya Taeko, Ogiso-Tanaka Eri, Mizobuchi Ritsuko, Fukuoka Shuichi, Yano Masahiro
National Agriculture and Food Research Organization (NARO), Institute of Crop Science, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8518, Japan.
National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan.
Breed Sci. 2019 Jun;69(2):352-358. doi: 10.1270/jsbbs.18172. Epub 2019 May 9.
IR64 is one of the world's most popular rice cultivars. To collect genetic factors involved in controlling its heading date, we developed 70 reciprocal advanced-backcross populations with a total of 6284 individuals at the BCF generation from crosses between Koshihikari and IR64. We detected 29 QTLs associated with heading date on chromosomes 3, 5-8, 10, and 12. Twenty QTLs were located in the same chromosome regions as previously isolated heading date genes (, , , , , , and ). The rest were located in other chromosome regions. We found more number of QTLs than previous studies using mapping populations of IR64. Fine mapping in additional advanced-backcross populations clearly revealed that QTLs on the long arm of chromosome 7 are overlapping and seem to be a novel genetic factor for heading date because of their different locations from . Our results suggest that the difference in heading date between IR64 and Koshihikari is genetically controlled by many factors, and that a non-functional allele of contributes to early heading of IR64 in the genetic background of functional alleles of other heading date QTLs and genes such as and .
IR64是世界上最受欢迎的水稻品种之一。为了收集控制其抽穗期的遗传因素，我们从越光和IR64的杂交后代中，在回交一代（BCF）培育了70个相互回交高世代群体，共6284个个体。我们在第3、5至8、10和12号染色体上检测到29个与抽穗期相关的数量性状基因座（QTL）。其中20个QTL位于与先前分离的抽穗期基因相同的染色体区域（、、、、、和）。其余的位于其他染色体区域。我们发现，与之前利用IR64作图群体的研究相比，检测到的QTL数量更多。在另外的回交高世代群体中的精细定位清楚地表明，第7号染色体长臂上的QTL相互重叠，由于其与不同的位置，似乎是一个控制抽穗期的新遗传因素。我们的结果表明，IR64和越光之间抽穗期的差异受许多因素的遗传控制，并且在其他抽穗期QTL和基因（如和）功能等位基因的遗传背景下，的一个无功能等位基因导致了IR64的早抽穗。
