Recurrent Selection to Alter Grain Phytic Acid Concentration and Iron Bioavailability

Iron is an important micronutrient and Fe deficiency is a global health concern. Phytic acid inhibits Fe absorption and cannot be digested by monogastric livestock or humans. High phytate concentration in staple crops may be one of the contributing factors for the high incidence of anemia in developing countries because of its inhibiting effect on Fe absorption. In seeds, it serves as the main storage compound for P. Low phytic acid mutants (lpa) in maize (Zea mays L.) have improved Fe bioavailability, but they have poor germination. Our objective was to develop both low phytic acid (LPA) and high phytic acid (HPA) maize populations using recurrent selection and to compare seed quality and Fe bioavailability among the HPA and LPA populations and lpa mutant lines. Three cycles of selection were performed in two broad-based synthetic populations, BS11 and BS31. The resulting HPA and LPA populations were significantly different in phytic acid concentration in the BS11-derived populations (P < 0.05) but not in the BSS31-derived populations (P > 0.05). The BS11LPA maize population had improved seed germination (13-16%; P < 0.05), and Fe bioavailability was not statistically different (P > 0.05) than the lpa mutant inbred lines. We conclude that recurrent selection for phytic acid levels may be a viable approach for improving Fe bioavailability of grain while maintaining seed quality.