基于染色体单片段代换系的水稻粒形QTL定位

Mapping of QTLs for Grain Shape Using Chromosome Single Segment Substitution Lines in Rice(Oryza sativa L.)

水稻的粒形是影响水稻产量和品质的重要因子之一,是由多基因控制的数量性状。染色体单片段代换系由于减少了个体间遗传背景的干扰,已经成为鉴定复杂性状QTL的新型遗传材料。本研究以广陆矮4号为受体,日本晴为供体的119个染色体单片段代换系群体为试验材料,通过单因素方差分析和Dunnett’s多重比较,测验单片段代换系与受体亲本之间粒形的差异,鉴定了代换片段上粒形相关的QTL。以P≤0.001为阈值,共检测到39个粒形相关的QTL。其中,粒长相关的19个,其加性效应值为0.18～1.06mm,加性效应百分率为2.40%～14.13%;粒宽相关的14个,其加性效应值为0.09～0.31mm,加性效应百分率为2.71%～9.15%;粒厚相关的6个,其加性效应值为0.05～0.10mm,加性效应百分率为2.14%～4.46%。这些QTL的鉴定为进一步精细定位并克隆相应QTL和高产、优质水稻新品种的分子标记辅助选择奠定了基础。

Grain shape is one of the important factors determining rice yield and grain quality, it is a typical quantitative trait controlled by multiple genes. As novel research material, chromosome single segment substitution lines are useful in QTL identification because of minimizing the interference of genetic background among plants. In this study, QTLs for grain shape were identi- fied with 119 rice chromosome single segment substitution lines derived from Nipponbare as donor parent in the background of Guanglu＇ai 4 by one-way analysis of variance and Dunnett＇s test for means comparisons between chromosome single segment substitution lines and the recipient parent Guanglu＇ai 4. A total of 39 QTLs for grain shape were identified on 11 chromosomes except chromosome 10 with a significance of P〈0.001. Among them, 19 QTLs were identified for grain length, with the additive effect from 0.18 mm to 1.06 mm and the additive effect percentages from 2.40% to 14.13%; 14 QTLs were identified for grain width, with the additive effect from 0.09 mm to 0.31 mm and the additive effect percentages from 2.71% to 9.15%; and 6 QTLs were identified for grain thickness, with the additive effect from 0.05 mm to 0.10 mm and the additive effect percentages from 2.14% to 4.46%. The results are important for the QTLs cloning and molecular breeding office grain shape.