Post on 25-Dec-2015
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
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
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
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
Source: www.ncga.com
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
Source: www.ncga.com
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.
Source: www.ncga.com
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,
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