Ears of orange maize lines following harvesting, on experimental plots at the Zambia Agriculture Research Institute (ZARI). This maize is orange because it contains high levels of beta-carotene, the same substance that give carrots their color. Beta-carotene is a provitamin, and is converted to vitamin A within the human body.
Maize is the staple food for more than one billion people in sub-Saharan Africa and Latin America, but it is generally poor in provitamin A. It is estimated that between one third and half of all Zambian children suffer from vitamin A deficiency, which weakens their vision and immune systems, retards their growth, makes them more vulnerable to various diseases, and reduces their quality of life. In all, night blindness and other health problems caused by vitamin A deficiency affect more than 5 million children and nearly 10 million pregnant women, according to the World Health Organization (WHO).
CIMMYT works with ZARI as part of HarvestPlus, a CGIAR challenge program that uses biofortification to improve the nutritional value of staple foods. The HarvestPlus maize team uses conventional breeding to create maize hybrids and open-pollinated varieties rich in provitamin A. In the research shown here, ZARI is evaluating advanced experimental varieties for yield and agronomic characteristics; the best of these will be tested for provitamin A content. Furthermore, scientists in CIMMYT and other organizations are now producing a new generation of varieties with more provitamin A than ever before. Alleles that can boost beta-carotene levels in grain, rare and previously found only in temperate maize, are being bred into tropical maize for developing countries.
For more about CIMMYT’s work in breeding biofortified maize rich in provitamin A, see the following e-news stories: – “Rare genetic variant in maize gives grain more pro-vitamin A”, 2010, available online at: http://www.cimmyt.org/newsletter/231-2010/617-rare-genetic-variant-in-maize-gives-