title: Agronomic problems related to provitamin A carotenoid-rich plants.
abstract: OBJECTIVE
  Review how agricultural systems might be changed to increase the vitamin A density of diets in developing countries to provide sustainable solutions to vitamin A deficiency globally.
  
  
  METHODS
  Develop agricultural systems that not only assure calorie adequacy for people, but also address vitamin A density in diets.
  
  
  METHODS
  Agricultural systems could be modified in some developing nations in ways that would provide adequate dietary amounts of provitamin A carotenoids from plant food sources.
  
  
  METHODS
  Infants and children of low-income families are most at risk of developing vitamin A deficiency in developing countries.
  
  
  METHODS
  Cropping systems could be modified to include more vegetable and fruit crops containing higher bioavailable amounts of provitamin A carotenoids in some countries. Additionally, cultural practices could be modified through education, agricultural extension and/or social marketing to insure that the bioavailable provitamin A carotenoid levels in food crops are optimized. Staple food crops could be improved as sources of provitamin A carotenoids by traditional plant breeding and/or by genetic engineering efforts.
  
  
  RESULTS
  Currently, many techniques are available to increase the vitamin A content of diets through sustainable food-based approaches. Agricultural approaches should be examined closely to finding sustainable food-based system solutions to vitamin A deficiency globally.
  
  
  CONCLUSIONS
  The world community should strive to find food-based system approaches to eliminating vitamin A deficiency. Modifying agricultural systems in ways that will not only maximizing food production, but also insure nutritional adequacy of vitamin A is a desirable goal for many developing countries.
authors.affiliation: U.S. Department of Agriculture, Agriculture Research Service, U.S. Plant, Soil and Nutrition Laboratory, Cornell University, Ithaca, NY 14853-2901, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Welch
mesh_terms: D000383:Agriculture; D002338:Carotenoids / Q000008:administration & dosage*; D004032:Diet; D005818:Genetic Engineering; D006801:Humans; D010945:Plants, Edible / Q000737:chemistry* / Q000235:genetics; D014801:Vitamin A / Q000008:administration & dosage*
chemical_list: D014801:Vitamin A; D002338:Carotenoids