水稻籽粒锌含量的QTL定位

QTL Mapping for Zinc Content in Rice Grains

锌元素的营养失衡已成为影响人类健康的最重要因素之一,籽粒锌含量的QTL(quantitative trait loci)定位对研究富锌水稻的遗传育种具有重要的意义。以水稻(Oryza sativa L.)亲本奉新红米和明恢100杂交的145个株系的F2群体为实验材料,利用92个SSR(simple sequence repeat)标记对水稻籽粒锌含量进行了QTL定位,共检测到3个QTLs,分别定位于第3、6和11染色体上,对表型变异的贡献率分别为4.97%、12.75%和7.74%。其中位于第3染色体上的分子标记RM186和RM168之间的QZN3对表型变异的贡献率最大,其增效等位基因来自亲本明恢100,表现为部分显性。3个QTLs的联合贡献率为25.46%,具有基因累加效应。该研究结果有利于深入理解水稻锌含量的遗传基础,为锌含量的QTL精细定位、基因克隆和分子标记辅助选择提供依据。

Zinc malnutrition has been one of most essential causes of harm to human health. Quantitative trait loci （QTL） for zinc content in rice grains is of great significance to the study of zinc-rich rice genetics and in zinc breeding programs. We used 145 F2 lines from the cross between Fengxinhongmi and Minghui100 rice to detect QTL associated with zinc content with 92 simple sequence repeat markers covering the whole rice genome. A total of 3 QTL for zinc content were detected on chromosome 3, 6, and 11 and accounted for 4.97%, 12.75% and 7.74% of the phenotypic variance, respectively. Among them, QZN3 was located between RM 186 and RM 168 on chromosome 3 and contributed the most to phenotypic variation. The favorable alleles of QZN3 for zinc content originated from Minghui 100, with partial dominant effects. The total contribution of the 3 QTL was 25.46%. This study has laid a foundation for mapping and cloning QTL and molecular-marker-assisted selection of zinc content in rice.