Comparative Mapping Suggests Repeated Selection of the Same Quantitative Trait Locus for High Leaf Photosynthesis Rate in Rice High-Yield Breeding Programs
Comparative Mapping Suggests Repeated Selection of the Same Quantitative Trait Locus for High Leaf Photosynthesis Rate in Rice High-Yield Breeding Programs
复制标题
DOI：
10.2135/cropsci2012.03.0179
复制
发表时间：
2012-11-01
期刊：
影响因子：
2.3
通讯作者：
Kondo, Motohiko
中科院分区：
文献类型：
--
作者：
Takai, Toshiyuki;Arai-Sanoh, Yumiko;Kondo, Motohiko
水稻（Oryza sativa L.）产量由库、源和植物结构之间的关系决定。“高丽号”是从“IR 8”和“东一号”衍生而来的高产水稻品种，植株矮小，库容量大，光合速率高。以往的研究表明，半矮秆1（sd 1）和粒数1A（GN 1A）的等位基因，分别赋予半矮秆株型和大穗，已被反复选择在育种程序中的高产育种过程中。然而，到目前为止，还没有发现与光合作用相关的遗传因素在育种计划中被选择。在这项研究中，我们进行了光合相关性状的数量性状位点（QTL）的比较定位使用三个F-2群体：'越光' x高纳，越光x东吉，越光x IR 8。比较3个群体的QTL位置发现，每个群体都有一个QTL位于第4染色体长臂上的同一位置，且高光合作用相关性状的等位基因来自每个群体的高产亲本。对高成家系的进一步基因型分析显示，与IR 8和高成相关的品种在4号染色体长臂上具有相同的基因型。这些结果表明，育种家已经选择了有利的等位基因的光合作用QTL在第4染色体上的几个育种计划，以高产。
Rice (Oryza sativa L.) yield is determined by the relationship between sink, source, and plant architecture. 'Takanari', a high-yielding rice variety descended from 'IR8' and 'Tongil', shows a semidwarf plant stature and has a large sink size and high photosynthesis rate. Previous studies have revealed that alleles of semi-dwarf1 (sd1) and GRAIN NUMBER1A (GN1A), which confer a semidwarf plant type and large panicles, respectively, have been selected repeatedly in breeding programs during the process of breeding for high yield. Until now, however, no genetic factors related to photosynthesis have been identified as having been selected in breeding programs. In this study, we conducted comparative mapping of quantitative trait loci (QTLs) for photosynthesis-related traits using three F-2 populations: 'Koshihikari' x Takanari, Koshihikari x Tongil, and Koshihikari x IR8. Comparison of QTL locations in the three populations revealed a QTL in the same location on the long arm of chromosome 4 in each one, with the allele for higher photosynthesis-related traits coming from the higher-yielding parent of each population. Further genotypic analysis of the Takanari pedigree revealed the same genotype on the long arm of chromosome 4 in varieties related to IR8 and Takanari. These results suggest that breeders have selected the favorable allele of the QTL for photosynthesis on chromosome 4 in several breeding programs for high yield.