Breeding for nutritional characteristics in cereals.

Extensive genetic variation within large species such as the major cereals can be confidently expected for any new trait of interest. This has now been extensively demonstrated for the nutrient content of cereal grains that is of interest under deficient conditions both to human nutritionists and to cereal agronomists. As cereals are eaten in large quantity by practically everyone, they are the ideal vehicles for changing the balance of nutrient intake of the whole human population. Doing so appears to be necessary as the World Health Organization has identified deficient micronutrient intake in well over half of all people globally, notably women and children. Of major concern are iron, zinc, selenium iodine, calcium and vitamin A-related carotenoids. Our results show that for any staple so far studied, the intake of iron, calcium and zinc from cereals can be doubled, and the content/intake of essential carotenoids can be increased by much greater factors. To prove to rigid scientific standards that greater intake results in greater absorption and measurable health benefits is quite difficult, but it is currently being pursued in various ways. This proof of bioavailability is all that impedes implementation in breeding programs.