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Origin Domestication and History of Some Important Crops
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Origin domestication and history of some important crops
The origins of agriculture and domesticated crops are intertwined, and the change from a hunter-gatherer
mode to tillage, sowing and harvesting was one of the major technologcal innovations of humankind.
There is good evidence that this occurred some 10,000 years ago in several different locations, and
involved the domestication of wild-relatives of the major crops (see History of Agriculture).
Domestication involves changes in the genetic makeup and morphological appearance of plants (and
animals). These changes occur because people select the variations of a wild plant that best suit their
needs. If the desired features can be passed to offspring, over generations of planting and harvesting, the
strains of plants grown change. Despite the fact that these domesticated varieties of plants are preferred
over their original forebears, the wild-relatives of crop plants continue to be an important resource.
Reserves of wild plants offer a pool of genetic diversity. Traits of plants that might have been lost in
domestication, sometimes become crucial for protection of domesticated crops from stress and disease
(seePlant breeding). Maintaining wild strains for their gene pool helps ensure food security. Knowledge of
crop origins is thus of considerable practical importance, even when these original strains are no longer
harvested as crops.
Development today of new crops (such as perennial alternatives of currently used annual staples) has
potential value in helping meet serious current agricultural challenges such as the need for water use
efficiency, better management of land salinization, and soil conservation.
Six independent centers of crop origin can be nominated [1] ):
Mesoamerica (Southern Mexico and Northern Central America): Maize, Phaseolus beans, Sweet
potato, tomato
The Andes of South America: Potato, cassava (manioc), pineapple
Southwest Asia (including the "Fertile Crescent": Wheat, barley, pea, lentil
The Sahel region and Ethiopian highlands of Africa: Sorghum, coffee, melon, watermelon
China: Asian rice, soybean, adzuki bean, orange, apricot, peach, tea
Southeast Asia: Cucumber, banana, plantain
Development of Agriculture
Taking root around 12,000 years ago, agriculture triggered such a change in society and the way in which
people lived that its development has been dubbed the “Neolithic Revolution.” Traditional hunter-gatherer
lifestyles, followed by humans since their evolution, were swept aside in favor of permanent settlements
and a reliable food supply. Out of agriculture, cities and civilizations grew, and because crops and
animals could now be farmed to meet demand, the global population rocketed—from some five million
people 10,000 years ago, to more than seven billion today.
There was no single factor, or combination of factors, that led people to take up farming in different parts
of the world. In the Near East, for example, it’s thought that climatic changes at the end of the last ice age
brought seasonal conditions that favored annual plants like wild cereals. Elsewhere, such as in East Asia,
increased pressure on natural food resources may have forced people to find homegrown solutions. But
whatever the reasons for its independent origins, farming sowed the seeds for the modern age.
Plant Domestication
The wild progenitors of crops including wheat, barley, and peas are traced to the Near East region.
Cereals were grown in Syria as long as 9,000 years ago, while figs were cultivated even earlier;
prehistoric seedless fruits discovered in the Jordan Valley suggest fig trees were being planted some
11,300 years ago. Though the transition from wild harvesting was gradual, the switch from a nomadic to a
settled way of life is marked by the appearance of early Neolithic villages with homes equipped with
grinding stones for processing grain.
The origins of rice and millet farming date to the same Neolithic period in China. The world’s oldest known
rice paddy fields, discovered in eastern China in 2007, reveal evidence of ancient cultivation techniques
such as flood and fire control.
In Mexico, squash cultivation began around 10,000 years ago, but corn (maize) had to wait for natural
genetic mutations to be selected for in its wild ancestor, teosinte. While maize-like plants derived from
teosinte appear to have been cultivated at least 9,000 years ago, the first directly dated corn cob dates
only to around 5,500 years ago.
Corn later reached North America, where cultivated sunflowers also started to bloom some 5,000 years
ago. This is also when potato growing in the Andes region of South America began.
the Farming Revolution
Taking root around 12,000 years ago, agriculture triggered such a change in society and the way in which people
lived that its development has been dubbed the “Neolithic Revolution.” Traditional hunter-gatherer lifestyles, followed
by humans since their evolution, were swept aside in favor of permanent settlements and a reliable food supply. Out
of agriculture, cities and civilizations grew, and because crops and animals could now be farmed to meet demand,
the global population rocketed—from some five million people 10,000 years ago, to more than seven billion today.
There was no single factor, or combination of factors, that led people to take up farming in different parts of the world.
In the Near East, for example, it’s thought that climatic changes at the end of the last ice age brought seasonal
conditions that favored annual plants like wild cereals. Elsewhere, such as in East Asia, increased pressure on
natural food resources may have forced people to find homegrown solutions. But whatever the reasons for its
independent origins, farming sowed the seeds for the modern age.
Plant Domestication
The wild progenitors of crops including wheat, barley, and peas are traced to the Near East region. Cereals were
grown in Syria as long as 9,000 years ago, while figs were cultivated even earlier; prehistoric seedless fruits
discovered in the Jordan Valley suggest fig trees were being planted some 11,300 years ago. Though the transition
from wild harvesting was gradual, the switch from a nomadic to a settled way of life is marked by the appearance of
early Neolithic villages with homes equipped with grinding stones for processing grain.
The origins of rice and millet farming date to the same Neolithic period in China. The world’s oldest known rice paddy
fields, discovered in eastern China in 2007, reveal evidence of ancient cultivation techniques such as flood and fire
control.
In Mexico, squash cultivation began around 10,000 years ago, but corn (maize) had to wait for natural genetic
mutations to be selected for in its wild ancestor, teosinte. While maize-like plants derived from teosinte appear to
have been cultivated at least 9,000 years ago, the first directly dated corn cob dates only to around 5,500 years ago.
Corn later reached North America, where cultivated sunflowers also started to bloom some 5,000 years ago. This is
also when potato growing in the Andes region of South America began.