The document discusses the origin of agriculture, including identifying centers of origin for early domesticated plants. It outlines several theories for identifying centers of origin, proposed by scholars like De Candolle, Vavilov, Zhukovsky, and Harlan, which focused on places where wild plants were first domesticated based on archaeological evidence, naming conventions, and environmental factors. Key centers of origin for early domesticated plants included areas in China, India, the Near East, Mesoamerica, and South America. The document also provides brief examples of some of the earliest domesticated crops that originated in these regions.

1. Origin of Agriculture

2. Introduction
• Knowledge of time and place of origin is
important
– For taxonomists and plant breeders
– Present day plants are much different than the
wild varieties
• Genetically and morphologically different
• Several genes (characterisitcs) are selected
– Loss of plants is loss of gene pools from
which new traits can be retrieved

3. Introduction
• Humans turned non-agricultural to
agricultural way of life.
• Agriculture; horticulture and domestication
• Study history by
– Carbon dating
– Fossils
– Phytoliths

4. Why farm?
• Work by Lee and Devore
– !King bushmen of Kalahari desert of southern
Africa
• Selected plant for adequate diet
• 105 species were used
• Did not work hard
• Not due to mal-nutrition or poverty
• Not revolution but evolution

5. De Candolle (1883)
• Pioneering work
• Criteria for recognizing centers of origin
– Places where a plant grows spontaneously in
a wild state
– Places where fragments of plants in old
deposits and buildings (archeological and
palaeobotanical) are found
– Archives describing the adventures of
travelers.
– Philogical (naming) origin

6. Vavilov (1927)
• Center located in 20-45 degrees latitude
• 6-8 centers
• China
• India
• Central Asia
• Near East
• Mediterranean
• Ethiopia
• Mesoamerica
• South America

8. Zhukovsky (1968)
• Megagene centers
– China
– Indochina - Indochina
– Australia - New Zealand
– India
– Central Asia
– West Asia
– Mediterranean
– Africa
– Europe - Siberia
– Mexico & Central America
– N. America

10. Centers of Origin
• Primary center: Places where initial
formation of species has taken place
• Secondary centers: new species formed
due to mutations and hybridization. Has
wide variety of subspecies

11. Harlan (1971 and 1992)
• Centers and non-centers: three each
• Recently related biomes to cultivation
• Tundra – no cultivation
• Tropical: Sugar cane, banana, orange, mango
and cocoa. Root crops and coffee
• Temperate: cheery, apple, pear, grapes walnut,
millets and wheat
• Mediterranean: maize, rice, sorghum, cassava,
sweet potato, bean, peanut, yams
• Sea coast: coconut, cabbage, cotton, beet

13. Old World Centers
• The near east: 9,000 – 14,000 years ago.
Fertile crescent of Mesopotamia. Wheat,
barley, peas and vetch
• The far east: 7,000- 8,000 years ago.
China, Thailand, India. Rice, millet, rape
and hemp

14. New World Centers
• Eastern North America: Cherokee
Sunflower and cranberries
• Western North America: Pueblo Dwellers
Trees and shrubs; pine nuts and pigweed
• Mexico: Aztecs and Mayans; Corn and
beans
• South American: Inca; Potato and
chocolate

16. Agriculture to day
• 3% of land is used for cultivation
• US: 1.9 billion acres
– 310million acres for crop
– 650 million acres for animal
• Four major crops: 80% Corn, wheat soy
and hay
• All fruits and vegetable – 7% land
• Cotton – 4%