Maize is the staple food of the people of sub-Saharan African countries, where it is used as food for humans and feed for livestock. As food for humans, it comprises about 75–80% by weight of the food intake, particularly in poor rural communities. As animal feed, it comprises about 70% of the formulation, particularly for monogastric animals like poultry and pigs. In poor rural communities whole grain is often fed to livestock like chickens. The maize grain contains 75–85% of grain phosphorus (P) as a compound called phytic acid. The P in phytic acid is not available to the monogastric consumers (humans, pigs, poultry, fish), which do not secrete enzymes to digest this molecule, and it is excreted in the faecal matter, resulting in loss of P and pollution of the environment. The phytic acid molecule also chelates iron (Fe), zinc (Zn), calcium (Ca) and magnesium (Mg) cations as it passes through the gut, leading to deficiencies of these micronutrients to consumers of maize-based diets. Deficiencies of Fe and Zn in particular are well known in developing countries. Iron deficiency is a major cause of lasting brain damage and death in children and limits the work capacity of adults. Iron deficiency anaemia affects about 2 billion children and adults worldwide, the majority of them in Africa. Zinc deficiency is associated with difficulties in pregnancy and childbirth, compromised immune responses, low birth weights and stunted child growth. Deficiencies of Fe and Zn can therefore limit the intellectual capacity of communities, and the consumption of mainly maize diets with high levels of phytic acid makes the situation worse. Maize genotypes containing low levels of phytic acid (lpa) have been developed in some temperate germplasm. Nutrition studies using this lpa germplasm have indicated increased bioavailability of P, Zn, Fe and Ca in monogastric animals and a decrease in P excreted compared with feeds based on wild-type (normal) maize germplasm. The potential benefit of using lpa maize as human food and in feed formulations for livestock seems to be very high, particularly in poor communities that are subject to mineral nutrient deficiencies. No research has, however, been conducted to develop low phytic acid cultivars in tropical germplasm and study its effects on monogastric consumers in these environments. The objectives of this project are to develop lpa tropical maize varieties and test these varieties in feed experiments using monogastric animals. The development of lpa varieties will be achieved by chemical mutagenesis of seed for planting and pollen to be used in pollination to generate the mutations, and by introgression of lpa alleles from temperate maize germplasm into tropical maize germplasm using conventional backcrossing. Feeding experiments will be performed on chickens and pigs in the first instance and later on humans. The developed varieties will be tested for adaptability in replicated trials in contrasting sites and over several seasons in South Africa and other selected countries.