Progress in Breeding Low Phytate Crops

Populations that depend on grains and legumes as staple foods consume diets rich in phytic acid (myo-inositol-1,2,3,4,5,6-hexkisphosphate), the storage form of phosphorus in seeds. This compound binds tightly to important mineral nutrients such as iron and zinc, forming salts that are largely excreted. This phenomenon can contribute to mineral depletion and deficiency. As one approach to solving this and environmental problems associated with seed-derived dietary phytic acid, the U. S. Department of Agriculture and others have isolated cereal and legume low-phytic acid mutations and have used these to breed first-generation low-phytate hybrids, cultivars and lines of maize (Zea mays), barley (Hordeum vulgare), rice (Oryza sativa) and soybean (Glycine max). Seed phytic acid is reduced in these crops by 50-95%. The progress in the genetics, breeding and nutritional evaluation of low-phytate crops are reviewed in this article.