The Grass that Feeds Humankind By Manuel Corro AGED 4713 Fall 2002

Corn Origins and Dispersal to the World 5000 B.C 1500 B.C Asia Africa Europe

Maize History uMaize is a gigantic domesticated grass [Zea mays ssp. mays] of tropical Mexican origin. uCultivation of maize and the elaboration of its food products are inextricably bound with the rise of pre-Colombian Mesoamerican civilizations. uDue to its adaptability and productivity the culture of maize spread rapidly around the globe uSpaniards and other Europeans exported the plant from the Americas in the 15th and 16th centuries. u Maize is currently produced in most countries of the world and is the third most planted field crop (after wheat and rice).

Scientific Classification uFamily: Gramineae u Genus: Zea uSpecies:Mays uThere are more than varieties of corn. uCIMMYT germplasm bank has accessions, one third are Mexican. uINIFAP has an additional 570 accessions

Morphology of Maize See the handout

Maize Grain Types uColor –85% yellow-grained –10-12% white - grained –<10 % red-, purple-, black- grained material uHardness –80% dent or semident material –15% flint or semiflint material –5% floury maize (Andean zone) and –Waxy maize from China International market classified maize in terms of: color and hardness

CIMMYT recognizes 5 major production environments uLowland tropics uSubtropics uMid-altitude tropical uTropical highlands uTemperate zone Major regions are known as megaenvironments, defined in terms of climatic factors Mean temperature during growing season Elevation above sea level Rainfall Day length

Distribution of Maize Production Environments, early 1990s

Distribution of World Maize Production

uThe corn smut is a parasitic fungus that attacks the ears, stalks, and tassels of corn. uSmut galls or swellings are produced, which are used as food in some areas of Mexico, Central and South America u Corn smut in Mexico is known as Huitlacoche

How Important Could the Corn Be in Developing Countries uWithout corn millions of people would starve uMillions of small farmers grow corn all over the world

Corn Consumption per capita and corn use in Latin America, kg117 kg 62 kg kg Source:

Corn Research

Growth in maize yields, by region, (% average annual growth) Source: CIMMYT 1999

Corn production systems in developing countries uSmall Farmers < 20 ha u Mixed Farming uSelf consumption uLow technology uOpen polinization varieties (OPVs) uNo hybrids

How important could the corn be in Mexico?  70% of grain production  45 % of rainfed land and 6 % of irrigated land.  2.7 millions corn growers (68 % of total population employed in agriculture).  Corn yield varies from 1.4 Tons/ha to 5 tons /ha (average=2.4 tons/ha)  20 million metric tons/year  Small size of land - small yield /ha, small income  White corn the most important

Mexican food based on maize u Dough (masa) –tamales (wrapped with husk or plantain leaf) –with any kind of meat inside prepared with some spices uTortilla –Enchiladas –Quesadillas –Tacos –Tostadas uGrain –Pozole (hominy soup) with pork and/or chicken meat –Pozol (beverage southern Mexico) –Pinole ( maize flour to prepare other dishes)

How important could the corn be in the U.S.? u 24 % of cropland u 72, 604, 000 acres u 45 % of crop production u $ 20 Billions worth u 40 % of world corn production u 70 % of world exports Source:

Corn Usage in U.S., 1999 Source: Consumption per capita 133.kg uCorn flakes usoda sweetened w/corn syrup ucorn-fed beef ucorn-fed Chicken uPet food

WHAT CAN YOU GET FROM A BUSHEL OF CORN? u32 pounds of corn starch or u33 pounds of corn sweetener or u2.5 gallons of ethanol PLUS u1.6 pounds of corn oil u11.4 pounds of 21% protein gluten feed u3 pounds of 60% gluten meal Source:  One bushel of corn will sweeten more than 400 cans of soda.

WHAT CAN YOU GET FROM A BUSHEL OF CORN? uA bushel of corn fed to livestock produces  5.6 pounds of retail beef or  13 pounds of retail pork or  19.6 pounds of chicken or  28 pounds of catfish. Source:

World supply uSix nations uUSA, China, Brazil, Mexico, France, and Argentina produce 75% of the world's maize supply

World Corn Production FAS.USDA, October 2000

Major Corn producing states Source: The maize page Iowa State U. t 82% of total production in US is within 6 states t Iowa t Illinois t Nebraska t Minnesota t Indiana t Ohio t Iowa leads the group with 22% of total national production which is 8.5% of total world production,

World corn imports Source:

World Issues about Corn uTrade uBiotechnology uBiodiversity

Biotechnology Crop Science Society of America defines biotechnology research as: uThe development of products requiring engineering technologies or using technologies such as recombinant deoxyribonucleic acid (DNA) techniques for the modification and improvement of biological systems

Biotechnology and Maize uReasons for applying biotech on maize –Economic importance –Commercial maize growers use hybrids –Maize consumed in most of industrialized countries with sophisticated research systems u Transposons: unusual feature of maize –Jumping genes that have the ability to move from one location to another within the genome, causing mutations.

Applications of biotechnology to maize breeding uMolecular genetics –identify one or more genes that confer a desired characteristics on maize plants and use molecular markers to identify in successive generations of plants that possess the gene or genes of interest u Genetic Engineering –inserting into maize plants and obtain expression of alien genes; these genes may be obtained from other organisms (plants or animals)

Applications of Molecular genetics uFingerprints: identify DNA –identifying genotypes –Monitoring genetic diversity in breeding materials –Efficient management of genetic resources uQuantitative trait locus mapping (QTL) uComparative mapping uMarker-assisted selection

Applications of Genetic Engineering uTransgenic maize, –trait genes and gene regulators uPest-resistance maize –Insertion of Bt (Bacillus thuringiensis) genes uHerbicide-resistance maize

Any questions ?