Directorate of Rice Research, Hyderabad, India.
Gene. 2012 Oct 25;508(2):233-40. doi: 10.1016/j.gene.2012.07.054. Epub 2012 Aug 6.
Identifying QTLs/genes for iron and zinc in rice grains can help in biofortification programs. 168 F(7) RILs derived from Madhukar×Swarna were used to map QTLs for iron and zinc concentrations in unpolished rice grains. Iron ranged from 0.2 to 224 ppm and zinc ranged from 0.4 to 104ppm. Genome wide mapping using 101 SSRs and 9 gene specific markers showed 5 QTLs on chromosomes 1, 3, 5, 7 and 12 significantly linked to iron, zinc or both. In all, 14 QTLs were identified for these two traits. QTLs for iron were co-located with QTLs for zinc on chromosomes 7 and 12. In all, ten candidate genes known for iron and zinc homeostasis underlie 12 of the 14 QTLs. Another 6 candidate genes were close to QTLs on chromosomes 3, 5 and 7. Thus the high priority candidate genes for high Fe and Zn in seeds are OsYSL1 and OsMTP1 for iron, OsARD2, OsIRT1, OsNAS1, OsNAS2 for zinc and OsNAS3, OsNRAMP1, Heavy metal ion transport and APRT for both iron and zinc together based on our genetic mapping studies as these genes strictly underlie QTLs. Several elite lines with high Fe, high Zn and both were identified.
鉴定水稻籽粒中铁和锌的 QTL/基因有助于生物强化计划。利用 Madhukar×Swarna 衍生的 168 个 F(7)RIL 对糙米中铁和锌浓度进行 QTL 作图。铁含量范围为 0.2-224ppm，锌含量范围为 0.4-104ppm。使用 101 个 SSR 和 9 个基因特异性标记进行全基因组作图，在染色体 1、3、5、7 和 12 上发现 5 个与铁、锌或两者都显著相关的 QTL。总共鉴定出这两个性状的 14 个 QTL。铁的 QTL 与染色体 7 和 12 上锌的 QTL 共定位。在所有的 14 个 QTL 中，有 10 个候选基因与铁和锌的体内平衡有关。另外 6 个候选基因靠近染色体 3、5 和 7 上的 QTL。因此，基于我们的遗传图谱研究，OsYSL1 和 OsMTP1 是种子中高铁和高锌的高优先级候选基因，用于铁，OsARD2、OsIRT1、OsNAS1、OsNAS2 用于锌，OsNAS3、OsNRAMP1、重金属离子转运和 APRT 用于铁和锌，因为这些基因严格控制 QTL。鉴定出了一些具有高铁、高锌和两者的优良品系。
