Nutritional enhancement of rice for human health: the contribution of biotechnology.

Micronutrient malnutrition is widespread, especially in poor populations across the globe where daily caloric intake is confined mainly to staple cereals. Rice, which is a staple food for over half of the world's population, is low in bioavailable micronutrients required for the daily diet. Improvements of the plant-based diets are therefore critical and of high economic value in order to achieve a healthy nutrition of a large segment of the human population. Rice grain biofortification has emerged as a strategic priority for alleviation of micronutrient malnutrition. Nutritional enhancement of crops through conventional breeding is often limited by the low genetic variability for required dietary micronutrient levels. In this case, biotechnology strategies offer effective and efficient perspectives. In this review, we discuss genetic engineering approaches that have been successful in the nutritional enhancement of rice endosperm. These advancements will make substantial contributions to crop improvement and human nutrition. Their practical application, however, also demands visionary changes in regulatory policies and a broader consumer acceptance.