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

The Grass that Feeds Humankind

By Manuel Corro

AGED 4713Fall 2002

Corn Origins and Dispersal to the World

5000 B.C

1500 B.C

Asia

Africa

Europe

Maize History

Maize is a gigantic domesticated grass [Zea mays ssp. mays] of tropical Mexican origin.

Cultivation of maize and the elaboration of its food products are inextricably bound with the rise of pre-Colombian Mesoamerican civilizations.

Due to its adaptability and productivity the culture of maize spread rapidly around the globe

Spaniards and other Europeans exported the plant from the Americas in the 15th and 16th centuries.

Maize is currently produced in most countries of the world and is the third most planted field crop (after wheat and rice).

Scientific Classification

Family: Gramineae Genus: Zea Species:Mays

There are more than 14 000 varieties of corn.

CIMMYT germplasm bank has 10965 accessions, one third are Mexican.

INIFAP has an additional 570 accessions

Morphology of Maize

See the handout

Maize Grain Types

Color – 85% yellow-grained– 10-12% white - grained– <10 % red-, purple-, black-

grained material Hardness

– 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

Lowland tropics

Subtropics

Mid-altitude

tropical

Tropical highlands

Temperate 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

0

20

40

60

80

100

Tropicallowland

Tropical Mid TropicalHigh

Subtropical Temperate

% o

f to

tal are

a

Developing countries

Industrialized countries

Distribution of World Maize Production

The corn smut is a parasitic fungus that attacks the ears, stalks, and tassels of corn.

Smut galls or swellings are produced, which are used as food in some areas of Mexico, Central and South America

Corn smut in Mexico is known as Huitlacoche

How Important Could the Corn Be in Developing Countries

Without corn millions of people would starve

Millions of small farmers grow corn all over the world

Corn Consumption per capita and corn use in Latin America,

1998

210 kg 117 kg

62 kg

189.4 kg

48%

40%

12%

Food Feed

Others

Source: www.cimmyt.org

Corn Research

Growth in maize yields, by region, 1961-97(% average annual growth)

Region 1961-70 1971-80 1981-90 1991-97

Latin America 1.98 2.12 0.30 3.10

Mexico and CentralAmerica

2.23 3.35 0.30 1.46

Andean Zone 1.36 1.84 0.68 1.61

Southern Cone 1.66 1.45 0.33 3.92

Sub-Saharan Africa 1.09 1.16 0.93 3.57

South, East, andSoutheast Asia

4.19 3.87 2.93 1.69

Developing countries 2.91 3.11 1.66 2.27

Industrialized countries 3.11 1.77 1.14 1.73

Source: CIMMYT 1999

Corn production systems in developing countries

Small Farmers < 20 ha

Mixed Farming Self consumption Low technology Open polinization

varieties (OPVs) No 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 Dough (masa)

– tamales (wrapped with husk or plantain leaf)– with any kind of meat inside prepared with

some spices Tortilla

– Enchiladas– Quesadillas– Tacos– Tostadas

Grain – 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.?

24 % of cropland 72, 604, 000 acres 45 % of crop production $ 20 Billions worth 40 % of world corn production 70 % of world exports

Source: www.ncga.com

Corn Usage in U.S., 1999


Consumption per capita133.kg

Corn flakes soda sweetened

w/corn syrup corn-fed beef corn-fed Chicken Pet food

WHAT CAN YOU GET FROM A BUSHEL OF CORN?

32 pounds of corn starch or 33 pounds of corn sweetener or 2.5 gallons of ethanol PLUS

1.6 pounds of corn oil 11.4 pounds of 21% protein gluten feed 3 pounds of 60% gluten meal


One bushel of corn will sweeten more than 400 cans of soda.

WHAT CAN YOU GET FROM A BUSHEL OF CORN?

A bushel of corn fed to livestock produces

5.6 pounds of retail beef or13 pounds of retail pork or19.6 pounds of chicken or 28 pounds of catfish.


World supply

Six nations

USA, China, Brazil, Mexico,

France, and Argentina

produce 75% of the world's

maize supply

World Corn Production 2000-2001

WORLD24%

China18%

Brazil6%

Mexico3%

France3%

USA43% Argentina

3%

FAS.USDA, October 2000

Major Corn producing states

Source: The maize page Iowa State U.

82% of total production in US is within 6 states

Iowa

Illinois

Nebraska

Minnesota

Indiana

Ohio

Iowa leads the group with 22% of total national production which is 8.5% of total world production,

World corn imports


World Issues about Corn

Trade

Biotechnology

Biodiversity

Biotechnology

Crop Science Society of America defines

biotechnology research as:

The 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

Reasons for applying biotech on maize– Economic importance– Commercial maize growers use hybrids– Maize consumed in most of industrialized countries

with sophisticated research systems

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

Molecular 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

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

Fingerprints: identify DNA– identifying genotypes– Monitoring genetic diversity in breeding materials– Efficient management of genetic resources

Quantitative trait locus mapping (QTL)

Comparative mapping

Marker-assisted selection

Applications of Genetic Engineering

Transgenic maize,

– trait genes and gene regulators

Pest-resistance maize

– Insertion of Bt (Bacillus thuringiensis) genes

Herbicide-resistance maize

Any questions ?

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

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