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

为了了解影响水稻产量的因素之一--叶片光合作用的遗传机理，本研究采用生态生理和遗传方法对高产高产品种高卡那利及其父本的叶片光合作用进行了研究。对光合作用相关性状的数量性状基因座(QTL)的比较定位表明，Takanari及其祖先IR8和Tongil在4号染色体的长臂上普遍存在一个QTL，且该等位基因的叶片含氮量增加。对Takanari家系的进一步基因分析表明，育种者已经在几个高产育种项目中选择了4号染色体上光合作用的有利等位基因。

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.