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Worl Population
- 6.68 billion in 2006
- increases by NOLA population everyday (211,000 people)
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Theory of Malthus (1800)
- population controlled by food production
- population increases geometrically (exponetialy) while food production increases arithmetically (linearly)
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Why hasnt the Malthus theory came true
popultion growth rates stablized in mor developed nations and food production had increased faster than predicted
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Green Revolution
- developing nation total food production has increases relative amount in developing than developed nation since 1960
- Dr. Norman Borlag is the father of green revolution
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Primary reasons for the Green Revolution
Plant Improvement, Breeding of higer yeilding, disease resistant, enviromentally responisve varieties
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Agronomic package:
tillage ferillzation, irrigation, pest controll
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CIMMYT-
IRRI-
USAID-
- International Maize (corn) and Wheat Improvemnet Center Mexico
- International Rice Research Instiute ( Philippines
- Land grant colleges through international ag programs
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Criticisms of Green Revolution
- Encourges input-intensice ag
- ingores local import crops ( less work on sorghum and millet)
- Some World regions been ingnored ( AFRICA)
- not accessivle to small farmers
- genetic vulnerbility (IRRI rice varieties)
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Remaing problesm of revolution
- high population groth rates in developing natiions
- food production had increaded very little since 1960 in many developing nations
- Distibution of food- 70% of people live where only 25% of world grain is produced
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Ag Revolution
tranistion of human society from hunter-gather to settler
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Techniques first introduced by early civilizations
Plant selection- ID plants that suppied food or fiber
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Cereals were first crops domesticated WHY
- easy to store (dry storage of grain)
- large seed easy to harvest and make food with
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Improved cultivation
first hand tools the latter animal powered tood for week control
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Orgin of Crops
- most presentd day crops have been developed by two process of
- domestications ( bringing some wild specied in cultivation) 7,000-10,000 years ago for most
- Selection(differential reproductio of those species)
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natural Selection
- Based on Survival of fittest
- Has directed applicatipon in some agro ecosystems ie. native range ( Darwin 1859)
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How has man modified with natural selectipon an succession in native pasture and range?
- fences ( often resulted in overgrazing)
- Removel of fire ( incasion of species such as read seder
- one specied of domesticated animal; more selective grazing vs wildlife
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Slection in crop breeding
- many crops so high selcted they only known under clultivation and raley seen wild
- aka CORN
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Orging of CROPS
CORN
WHEAT
POTATO
SOYBEAN
- Central America ----- U.S. Corn Belt
- Asic ------ US Central Plains
- S. America -------Western Europe
- Central China ------ America
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Why Know ceter of orgin
- source of greats biological diversity
- variation in forms an types of the plant
- wild relatives can be used as sourse of germplasmfor morder crop breeding
- germplasm
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GERMPLASM
- gentic material preserved as seed or living plants
- DNA for the species or variety
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Plant breeding
- hybrid vigor
- varity improvment
- pest resistance
- stress tolerance
- adaptation to harvest
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Exampla on imported uses of germplasm in crop improvement
- Semi dwarf wheat- NORIN 10 wheat form jampan WWII better adapation ot both and hand an machine harvest
- Russian What Aphid- new pest arriced in 1986 USDA in stillwater leads resistance working diverse germplasm
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Concerns fo rhte future
- preserving bbiological diversity in the face of destuction of natural ecosystems(tropical, rain forest, wetlands)
- agencies involved with germplasm preservations: USDA national seed storage laboratory (NSSL) Fort Collins, Co and INternational board of plant gentetic resources IBPGR in Rome
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Concerns for the future
- political limitation to free access of germplasm
- gentic engineering an patent right for newly devolped germplasm
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Tillage and managemt practice
many crops are compltly dependednt on man's intensice mangement and imputs into the soil for thier successful production
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Fertilization
manures and other organic matter were ussed as ferilizers by early civilization ( Romans and American Indians)
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Mechanization
1700's-1800's -- Tractor, steel plow, cotton gein reaper, thresher
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Fallow
- leave land idle ofr a growing season
- soil store moistrue in soil and releases nutriends from organic matter
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Crop rotation with legumes
- Cereal--> legume --> Cereal
- nitogen fixation by legume
- N2 gas from the air converted to protein in the plant by rhizobium bacteria living in root nodules
- some itrogen is left in soil for next crop
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Historical developements
- 1843= 1st ag research station - Rothamsterd
- 1862= Morrill Act - Land Grant Colleges
- 1888=HATCH Act - Experiment Stations
- 1914= Smith-lever Act- extension
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Major Contribustions of research
- plant breeding
- imporved crop and soil mangment practices
- development of ag chemicals and modern agricultural equipment
- understanding plant physiology
- use of remote sensing
- new thechniques to imporve efficiency of input use
- new developments in biotchnology and genetic engineering
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