March, 2002: Texcoco, Mexico
Each year, almost 12 million children die from malnutrition. Since people
in many developing countries rely on maize (corn) for as much as 30% of
the calories in their diets, scientists have been concentrating on producing
higher-yielding and more nutritious corn to supplement protein-deficient
diets. Three decades of field and laboratory research culminated in September
of 2000 when two scientists from the International Maize and Wheat Improvement
Center in Texcoco, Mexico, were awarded the World Food Prize. The prize-winning
corn they developed yields 10% more grain and 50% more of the amino acids
lysine and tryptophan than traditional varieties.
 Producing hybrid corn (cross breeding). |
Beginning in 1970, Surinder Vasal, a corn breeder, and Evangelina Villegas, a cereal chemist, were faced with the challenge of improving corn that had been successfully modified to increase its nutritional value but still had a chalky appearance, low yields, and disease susceptibility. After a decade of cross-breeding thousands of varieties of corn in conjunction with laboratory research, a more aesthetically pleasing and still nutritionally enhanced crop emerged. Then, in the late 1980s, other scientists came on board to help develop varieties of corn able to grow in different environmental conditions, such as acidic soils, and to resist drought and insects. Currently, more than eleven developing countries in Africa, Latin America, and Asia are growing this improved corn, called "quality protein maize," on over 2.5 million acres of land.
Additionally, the Africa Maize Stress Project, a division of CIMMYT (the Spanish acronym for the International Maize and Wheat Improvement Center), focuses on areas of the continent where poor soil fertility and drought are the major causes of crop failure. Currently, maize stress-testing sites are in operation in Cameroon, Ethiopia, Ghana, Kenya, and Nigeria, among other African countries.
Growing crops on South American soil offers its own unique set of challenges. For example, 80% of agricultural land in South America is acidic. Because of the increased food demand caused by expanding populations, about 50 million hectares of acidic savanna in Brazil, which had never been used for agriculture (at least in modern times), are now under cultivation. As a result, researchers based in regional experimental stations in Colombia have been focusing on acid-tolerant maize development as part of the Colombian Agricultural Research Corporation (also part of CIMMYT).
 Male and female corn plants. |
Corn, Zea maize, is a monocot in the grass, or Poaceae, family. This large family is represented by 668 genera and 9,500 species. While many members of the Poaceae have bisexual flowers, corn produces separate male and female flowers. Amino acids, such as lysine and tryptophan, are the building blocks of proteins; in all, 20 amino acids combine via covalent peptide bonds to form tens of thousands of proteins. Pellagra is a form of malnutrition caused by low-protein diets, especially those deficient in niacin and tryptophan. Pellagra is common in corn-eating communities, and the introduction of "quality protein maize" into those areas will have significant impact.
 The 20 amino acids. |
In addition to increased notoriety and professional satisfaction, Vasal and Villegas are enjoying the $250,000 associated with the World Food Prize (sponsored since 1990 by businessman and philanthropist John Ruan). Established in 1986 by Norman E. Borlaug, the award honors people who have made significant contributions to food nutrition, yield, and availability. (Borlaug won the Nobel Peace Prize in 1970 for developing a new, high-yielding strain of wheat in Mexico.) Villegas also basks in the honor of being the first woman to receive the World Food Prize. While these worthy recipients know this corn will not resolve all forms of malnutrition, it certainly offers essential proteins and higher-yielding crops to farmers and families who have little or no resources at their disposal.
References, Websites, and Further Reading
Adams, Lisa J. September 8, 2000. Two creators of high-protein corn honored. The Record, World Section.
Levetin, Estelle, and Karen McMahon. 1999. Plants and Society, 2d ed. New York: McGraw-Hill Companies, pp. 189-91.
Simpson, B.B., and Molly C. Ogorzaly. 1995. Economic Botany: Plants in Our World, 2d ed. New York: McGraw-Hill Companies, pp. 187-98.
http://www.cimmyt.org/
Main page for the International Maize and Wheat Improvement Center
http://www.botany.hawaii.edu/faculty/carr/po.htm
University of Hawaii at Manoa, Poaceae family page
Related Reading in Stern, Kingsley R. 2000. Introductory Plant Biology,
8th ed. New York: McGraw-Hill Companies.
Chapter 2: The Nature of Life
Covalent bonds, p. 19
Acids, bases, and the pH scale, p. 20
Proteins and amino acids, pp. 24-26
Chapter 8: Flowers, Fruits, and Seeds
Differences between monocots and dicots, pp. 129-30, including table 8.1
Structure of flowers, pp. 129-32
Chapter 14: Plant Propagation and Biotechnology
Traditional plant breeding: The Green Revolution, hybridization, Norman
Borlaug, pp. 242-44
Chapter 24: Flowering Plants and Civilization
The Grass Family (Poaceae), p. 454
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