Summary: | Clarifying the genetic basis of trace element accumulation is of great significance to breed new maize varieties with high quality. In this study, an integrated variant map with 1.25 million (M) SNPs and 489 inbred lines was used for a genome-wide association study on the accumulation of iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), cadmium (Cd) and Arsenic (As) in maize kernels. Seventeen SNPs linked with six genes were overlapped by different trace elements. After further analysis, 65 SNPs located in 28 genes with a <i>p</i>-value lower than 10<sup>−10</sup> were associated with Cd content by genome-wide association studies (GWAS). There was a 3.1-fold difference in Cd content between different groups, which was divided by SNP haplotype in <i>chr2.S_160782359</i>, <i>chr2.S_161045498</i> and <i>chr2.S_161273716</i>. The amino acid sequences of <i>GRMZM2G150608</i> and <i>GRMZM2G051367</i> only shared 68.85% and 88.16% similarity between B73 and Mo17, and the Cd content of Mo17 was 2.2-fold that of B73. In addition, 19 lines with higher contents of Fe, Zn, Cu, Mn and fewer contents of As and Cd were screened from GWAS associated populations. This study will lay a foundation for revealing the molecular mechanism of trace element accumulation in maize kernels and provide candidate genes for breeding new maize varieties with high nutritional quality.
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