Submitted to: Plant Breeding Reviews
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 21, 2007
Publication Date: January 3, 2009
Citation: Simon, P.W., Pollak, L.M., Clevidence, B.A., Holden, J.M., Haytowitz, D.B. 2009. Plant Breeding for Human Nutritional Quality. Plant Breeding Reviews. 31:325-415. Interpretive Summary: Nutritionists have noted that crop plants are the main source of dietary fiber, vitamins C and E, and nutritionally important pigments in the U. S. diet, and that many other nutrients come at least in part from crop plants consumed. Plant breeders have noted that there is much genetic variation in the content of nutrients in crops. Using input from nutritionists, plant breeders have made some advances in increasing the nutrient content of U.S. crops, for example higher vitamin A levels from modern carrots. We review those nutrients and note those for which intake in the U.S. are inadequate. Prospects for plant breeders to breed for higher nutrient intake are discussed. Both U.S. and international perspectives are considered. This research review is important to plant breeders interested in improving nutritional value of crops, nutritionists interested in potential changes in crop nutrient content as plant breeding advances, and consumers interested in the nutrient quality of foods.
Technical Abstract: With the advent of agriculture came a more reliable and abundant source of food and the nutrients that food supplies. Yet it only became obvious in the last several centuries that food is a complex mixture of components, each with independent roles in contributing to particular aspects of health. Not long after the time that Mendel’s work was rediscovered to provide a more scientific foundation for plant breeding a century ago, the first vitamins were described with the discovery of vitamin A in 1913 and several others thereafter. Differences in crop color due to carotenoids (yellow versus white corn) were soon associated with differences in vitamin A nutrition. With this report it might have been expected that plant breeders would include the improvement of nutritional quality as a basic breeding goal for all food and feed crops. In fact yellow corn virtually replaced white corn by 1970 because it was recognized to be a better animal feed. Yet the numerous challenges in producing the crop and delivering an acceptable commodity to the consumer must be met before nutritional quality comes to the attention of plant breeders. Working together, plant breeders and nutritionists can play a key role in sustaining the supply of dietary nutrients in the crops we breed where intake is adequate, and in developing strategies for increasing intake of those nutrients where intake is inadequate. This review provides plant breeders with a summary of nutrient requirements and nutrient consumption in the U.S., thanks to the extensive U.S. database available. Most of the dietary fiber, vitamins C and E, and nutritionally important pigments come from plants in the U.S. diet. Intake of several nutrients falls below recommended levels and these nutrients, in particular, are described in more detail from both the crop source and the plant breeding perspective. Plant breeders have identified much genetic variation that can be harnessed to improve crops and consequently the nutrient content and consumer appeal of plants contributing to our diet. Beyond those shortfall nutrients in the U.S., deficiencies for other nutrients are prevalent in other parts of the world, and breeding progress for these nutrients is also reviewed.