Improving iron and zinc value of rice for human nutrition
Micronutrient deficiency 'hidden hunge' + affects more than 3.7 billion people worldwide, predominantly women and children because of their physiological needs. Iron and zinc deficiencies cause impaired immune function, complications in pregnancy and childbirth, poor child growth and learning ability, and reduce labor productivity. In 1992, IRRI began to examine the effect of certain soil characteristics on the iron content in the grain and was expanded in 1995 to include zinc and collaboration with university of Adelaide, Australia for mineral analysis. Germplasm screening showed large genetic variation for Fe and Zn in brown rice. Common cultivars contain about 12mg kg-1 of iron and 25mg kg-1 Zn. Some traditional varieties have doubled these amounts. Genetics of high Fe trait showed the importance of additive and dominance gene action but less affected by environment. Moreover three QTLS for high Fe trait were tagged in rice chromosomes. High iron and zinc traits can be combined with improved agronomic traits. IRRI identified improved rice with good yielding ability and high concentration of iron and zinc in the grain. Because of the high consumption of rice in developing countries, the extra iron and zinc would have meaningful impact on human nutrition and health