Oladzad-Abbasabadi Atena, Kumar Ajay, Pirseyedi Seyed, Salsman Evan, Dobrydina Marina, Poudel Roshan Sharma, AbuHammad Wesam A, Chao Shiaoman, Faris Justin D, Elias Elias M
Department of Plant Sciences, North Dakota State University, Fargo, North Dakota 58108.
Arizona Plant Breeders Inc., Casa Grande, Arizona 85122.
G3 (Bethesda). 2018 Mar 2;8(3):923-932. doi: 10.1534/g3.117.300370.
Cadmium (Cd) is a heavy metal that has no known biological function and is toxic for many living organisms. The maximum level of Cd concentration allowed in the international market for wheat grain is 0.2 mg kg Because phenotyping for Cd uptake is expensive and time consuming, molecular markers associated with genes conferring low Cd uptake would expedite selection and lead to the development of durum cultivars with reduced Cd concentrations. Here, we identified single nucleotide polymorphisms (SNPs) associated with a novel low Cd uptake locus in the durum experimental line D041735, which has hexaploid common wheat in its pedigree. Genetic analysis revealed a single major QTL for Cd uptake on chromosome arm 5BL within a 0.3 cM interval flanked by SNP markers. Analysis of the intervening sequence revealed a gene with homology to an aluminum-induced protein as a candidate gene. Validation and allelism tests revealed that the low Cd uptake gene identified in this study is different from the closely linked gene, which also resides on 5BL. This study therefore showed that the durum experimental line D041735 contains a novel low Cd uptake gene that was likely acquired from hexaploid wheat.
镉（Cd）是一种重金属，尚无已知的生物学功能，且对许多生物体有毒。国际市场上小麦籽粒允许的镉浓度最高水平为0.2毫克/千克。由于对镉吸收进行表型分析既昂贵又耗时，与赋予低镉吸收能力的基因相关的分子标记将加快选择进程，并促使培育出镉浓度降低的硬粒小麦品种。在此，我们在硬粒小麦实验品系D041735中鉴定出与一个新的低镉吸收位点相关的单核苷酸多态性（SNP），该品系的谱系中有六倍体普通小麦。遗传分析揭示了在5BL染色体臂上一个0.3厘摩区间内存在一个控制镉吸收的单一主效数量性状位点（QTL），两侧为SNP标记。对中间序列的分析揭示了一个与铝诱导蛋白具有同源性的基因作为候选基因。验证和等位性测试表明，本研究中鉴定出的低镉吸收基因与同样位于5BL上的紧密连锁基因不同。因此，本研究表明硬粒小麦实验品系D041735含有一个可能从六倍体小麦获得的新的低镉吸收基因。
