Development and validation of breeder-friendly gene-based markers for and genes conferring low phytic acid in maize kernel.

Based on C (wild) to T (mutant) transition at amino acid position 1432 bp of gene, two dominant markers each specific to wild type () and mutant () allele were developed and validated across seven F populations. Joint segregation of these markers behaved in co-dominant fashion, clearly distinguishing heterozygote from two other homozygote genotypes. Full length sequence alignment between wild type () and mutant () allele revealed one transition mutation (A to G) and a co-dominant CAPS marker was developed which differentiated all three types of segregants across seven F populations. Across populations, segregants with (1.77 mg/g) and (1.85 mg/g) possessed significantly lower phytic acid compared to (2.58 mg/g) and (2.53 mg/g). Inorganic phosphorus was however higher in recessive homozygotes (: 0.77 mg/g, : 0.53 mg/g) than the dominant homozygotes (: 0.33 mg/g, : 0.19 mg/g). Overall, homozygous segregants of and showed 31% and 27% reduction of phytic acid, respectively. Analysis of phytate and inorganic phosphorous in the maize kernel in these segregating populations confirmed co-segregation of trait and markers specific to and . This is the first report of the development of breeder-friendly gene-based markers for and ; and it holds great significance for maize biofortification.