Studies on the origin of high-photosynthesis in rice high-yielding cultivar, Takanari, based on its pedigree analysis

为了解水稻叶片光合作用的遗传机制，采用生态生理学和遗传学方法，对水稻高产品种高成及其祖先的叶片光合作用进行了研究。对高成及其亲本IR8和Tongil的光合相关性状QTL定位结果表明，高成及其亲本均在第4染色体长臂上存在一个增加叶片含氮量的QTL。对高成家系的进一步基因型分析表明，育种者在几个高产育种计划中选择了4号染色体上光合作用QTL的有利等位基因。

To understand genetic mechanism of leaf photosynthesis, one of the factors related to rice yield, we investigated leaf photosynthesis in high-photosynthesis and high-yielding cultivar, Takanari, and its ancestors with eco-physiological and genetic methods. Comparative mapping of quantitative trait locus (QTL) for photosynthesis-related traits revealed that Takanari and its ancestors such as IR8 and Tongil commonly had a QTL on long arm of chromosome 4 with the allele increasing leaf N content. Further genotypic analysis of the Takanari pedigree suggested that breeders have selected the favorable allele of the QTL for photosynthesis on chromosome 4 in several breeding programs for high yield.