Genetic Variation and Breeding Potential of Phytate and Inorganic Phosphorus in a Maize Population

Seed P is predominantly bound in the organic compound phytate, which makes the bioavailability of P low for monogastric animals fed maize ( Zea mays L.)‐based diets. Decreasing phytate and increasing inorganic P (P i , an available form of P) concentrations in maize grain would be desirable to help ameliorate environmental problems associated with high P in feces. Our objective was to investigate the potential of improving the P profile of maize grain through breeding and selection. Ninety S 1 families from the BS31 population were evaluated at two locations for phytate, P i , and other grain quality and agronomic traits. Phytate concentrations ranged from 1.98 to 2.46 g kg −1 , and the broad‐sense heritability ( H ) was relatively low (0.60). Both genetic variance and H (0.84) were much greater for P i Few unfavorable genetic correlations were observed between either P i or phytate and other key economic traits. Also, selection differentials of multiple trait indices indicated that the P profile of maize grain and grain yield and moisture could be improved simultaneously. Many cycles of selection will be needed, however, to reach desirable phytate and P i concentrations, especially when selecting for multiple traits. Regardless, our results are encouraging given that the families evaluated were related S 1 families and the number of families was relatively small.