基于重测序的染色体片段代换系定位水稻抽穗期QTL

【目的】水稻的抽穗期是决定水稻产量及其适用性的重要农艺性状之一,是由多基因控制的数量性状。染色体片段代换系减少了个体间遗传背景的干扰,已经成为定位和克隆复杂性状QTL的重要材料。【方法】本研究以9311为受体,日本晴为供体构建的128个重测序的染色体片段代换系群体为试验材料,利用多元回归,结合Bin-map图谱,【结果】鉴定到6个在南京、扬州不同年份间稳定表达的抽穗期QTL,其中,qHD2.1被定位在第2染色体上的759 848 bp区间内;qHD2.2被定位在第2染色体上的45 286 bp区间内;qHD 3.1被定位在第3染色体上的147 931 bp区间内;qHD5.1被定位在第5染色体上的213 351 bp区间内;qHD5.2被定位在第5染色体上的442 305 bp区间内;qHD8.1被定位在第8染色体上的538 176 bp区间内。【结论】本研究为精细定位并克隆相应QTL,进而探明抽穗期QTL的分子调控机制奠定了基础。

Mapping of QTLs for Heading Date Using Whole-genome Re-sequenced Chromosome Segment Substitution Lines in Rice

【Objective】Heading date is an important agronomic trait in rice, it is a typical quantitative trait controlled by multiple genes. As novel research material, chromosome segment substitution lines are useful in QTL fine mapping and cloning because of minimizing the interference of genetic background among plants. 【Method】In this study, 128 whole-genome re-sequenced chromosome segment substitution lines derived from Nipponbare as donor parent in the background of 9311, were used for mapping QTLs for heading date by combining the sequencing-based Bin-map with multiple linear regression analysis. 【Result】Six QTLs for heading date were identified in two environments and two years. qHD2.1 was mapped in the region of 759 848 bp on the chromosome 2; qHD2.2 was mapped in the region of 45 286 bp on the chromosome 2; qHD 3.1 was mapped in the region of 147 931 bp on the chromosome 3; qHD5.1 was mapped in the region of 213 351 bp on the chromosome 5; qHD5.2 was mapped in the region of 442 305 bp on the chromosome 5; qHD8.1 was mapped in the region of 538 176 bp on the chromosome 8. 【Conclusion】The results are important for the QTLs cloning and provide a foundation for understanding molecular regulation mechanism of heading date in rice.