ORIGIN AND
DOMESTICATION
OF
CULTIVATED PLANTS
ORIGIN OF AGRICULTURE
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
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Possibly 10,000 yrs ago
Ties to end of Ice Age
Many differing opinions:
Vavilov – Russian plant geneticist
eight independent centers (1951)
Sauer – cradle in Southeast Asia
woody areas vs. river valleys
vegetative methods
Opinions (cont)
Harlan – opposed Vavilov’s eight centers
wide geographic areas called non-centers
three large independent systems:
- Near East and Africa
- China and Southeast Asia
- Mexico and South America
Bender – transition from hunter/gatherer
to producer
- profoundly changed human culture
Harlan;Hawkes – climatic/cultural factors
- motivated man to “invent agriculture”
Note: Approximates Vavilov’s Eight
Independent Centers
What Do We Know For Certain?
Definite evidence from archeological
sites:
- agricultural villages 8000-9000 B.C.
- Fertile Crescent
- diversity of crops:
wheat, barley, lentil, oats, vetch,
dates, grapes, olives, almonds,
figs, pomegranates
Chinese Center of Agriculture
- Became Important About 4000
Crops domesticated:
millet, chestnuts, hazelnuts,
peaches, apricots, mulberries,
soybeans, and rice
B.C.
Southeast Asia/Indonesia
- Domesticated Rice about 6000
other crops followed:
sugar cane, coconut, banana,
mango, citrus
B.C.
New World
Southern Mexico and Central America
5000 – 7000
B.C.
maize (corn), sweet potato, tomato,
cotton, pumpkin, peppers, squash,
avocado, pineapple
South America
Broad “non-center”
stretches from Chile northward to
Atlantic Ocean and eastward into
Brazil
- snap beans, lima beans 6000 B.C.
- other crops:
potato, peanut, pineapple, cashew,
Brazil nut, peppers, tobacco, tomato
Australia
Only one crop:
macadamia or Queensland nut
United States
No major cultivated crop origins
- relies on introduced crops
- many minor fruit and nut crops:
American grapes and plums, pecan,
chestnut, hickory nut, hazelnut,
black walnut, persimmon,
blueberry, raspberry, blackberry,
and cranberry
United States (cont)
Additional crops:
- sunflower (important oil crop)
- hops
- Jerusalem artichoke
- some grasses
- many ornamentals
- timber tree species
Methods of Plant Domestication
Vegetative (Asexual) Propagation
- observation/experience revealed
- some of the oldest woody plants:
grape, fig, olive, mulberry,
pomegranate, quince
- many tree fruit species native to
near east:
almond, apple, pear, cherry, walnut
Vegetative (Asexual) Propagation
(cont)
Many ancient plants:
- potato (tuber)
- sweet potato (an enlarged root)
- banana (rhizome)
- bamboo (rhizome)
- ginger (rhizome)
- filbert (layering)
- pineapple and date (suckering)
Methods of Plant Domestication
Seed (Sexual) Propagation
- harvesting wild grass seeds
led to two population types:
1) shattering - reseeded itself
2) nonshattering - harvested and resown
- nonshattering thus improved as
it was more easily harvested
Seed (Sexual) Propagation (cont)
Close planting of harvested seeds led to
better competition against weeds
-
stronger, vigorous plants
larger seeds increase germination
harvested crop from superior seed
unknowingly developed superior
Seed (Sexual) Propagation (cont)
Other desirable characteristics:
-
increased flower numbers
larger inflorescences
trend toward determinate growth
loss of seed dormancy
Sometimes change is slow/complex
Sometimes rapid with few genes