The usefulness of iron bioavailability as a target trait for breeding maize (Zea mays L.) with enhanced nutritional value

► Fe bioavailability varied significantly among maize hybrids in two of three trials. ► Heritabilities were moderately high (circa 0.6) for Fe bioavailability estimators. ► Fe bioavailability was not correlated with grain Fe concentration or grain yield. ► Zn and proA in grain inhibited and enhanced Fe bioavailability, respectively. ► Fe bioavailability can be a useful selection trait, and simple assays are needed.