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  2. The history of rice cultivation is an interdisciplinary subject that studies archaeological and documentary evidence to explain how rice was first domesticated and cultivated by humans, the spread of cultivation to different regions of the planet, and the technological changes that have impacted cultivation over time.

  3. Many historians believe that rice was grown as far back as 5000 years BC. Archaeologists excavating in India discovered rice which could be dated to 4530BC. However, the first recorded mention originates from China in 2800 BC.

    • Overview
    • Physical description
    • Domestication and cultivation
    • Rice processing and uses

    The cultivated rice plant grows to about 1.2 meters (4 feet) in height. It is an annual grass. The panicle, or inflorescence (flower cluster), is made of spikelets bearing flowers that produce the fruit or grain. Varieties differ greatly in the length, shape, and weight of the panicle and the overall productivity of a given plant.

    What countries are major producers of rice?

    More than 90 percent of the world’s rice is grown in Asia, principally in China, India, Indonesia, and Bangladesh, with smaller amounts grown in Japan, Pakistan, and various countries of Southeast Asia. Rice is also cultivated in parts of Europe, North and South America, and Australia.

    What nutrients are present in rice?

    The manner in which rice is processed affects its nutritional profile. Brown rice, where only the husk is removed, contains about 8 percent protein and small amounts of fats; it also has thiamine, niacin, riboflavin, iron, and calcium. White rice, where the husk and bran are removed, is greatly diminished in nutrients. Parboiled white rice retains most of the nutrients, and enriched rice has iron and B vitamins added to it.

    How important is rice as a source of food for humans?

    The cultivated rice plant is an annual grass and grows to about 1.2 metres (4 feet) in height. The leaves are long and flattened and are borne on hollow stems. The fibrous root system is often broad and spreading. The panicle, or inflorescence (flower cluster), is made up of spikelets bearing flowers that produce the fruit, or grain. Varieties differ greatly in the length, shape, and weight of the panicle and the overall productivity of a given plant.

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    In the 1960s the so-called Green Revolution, an international scientific effort to diminish the threat of world hunger, produced improved strains of numerous food crops, including that known as miracle rice. Bred for disease resistance and increased productivity, this variety is characterized by a short sturdy stalk that minimizes loss from drooping. Poor soil conditions and other factors, however, inhibited its anticipated widespread success.

    Many cultures have evidence of early rice cultivation, including China, India, and the civilizations of Southeast Asia. However, the earliest archaeological evidence comes from central and eastern China and dates to 7000–5000 bce. More than 90 percent of the world’s rice is grown in Asia, principally in China, India, Indonesia, and Bangladesh, with smaller amounts grown in Japan, Pakistan, and various Southeast Asian nations. Rice is also cultivated in parts of Europe, in North and South America, and in Australia.

    With the exception of the type called upland rice, the plant is grown on submerged land in the coastal plains, tidal deltas, and river basins of tropical, semitropical, and temperate regions. The seeds are sown in prepared beds, and when the seedlings are 25 to 50 days old, they are transplanted to a field, or paddy, that has been enclosed by levees and submerged under 5 to 10 cm (2 to 4 inches) of water, remaining submerged during the growing season. In hilly areas rice farms are commonly terraced to keep the paddies flooded at various elevations. Successful rice production depends on adequate irrigation, including construction of dams and waterwheels, and on the quality of the soil. Long periods of sunshine are essential. Rice yields vary considerably, ranging from 700 to 4,000 kilograms per hectare (600 to 3,500 pounds per acre). Adequate irrigation, which means inundation of the fields to a depth of several inches during the greater part of the growing season, is a basic requirement for productive land use.

    In Asia the paddy is cultivated in three main types of soil, including clays with a firm bottom within a few inches of the surface; silts and soft clays with soft bottoms becoming hard on drying; and peats and “mucks” containing peat, provided the depth of the peat is not excessive. Fields must be drained and dried before harvesting. When combine harvesters or binder threshers are employed, the grain must be dried to about 14 percent moisture so that no deterioration takes place in storage. When reaper binders are used, the crop is “shocked” in certain ways so that the grain is protected from rain.

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    The harvested rice kernel, known as paddy, or rough, rice, is enclosed by the hull, or husk. Milling usually removes both the hull and bran layers of the kernel, and a coating of glucose and talc is sometimes applied to give the kernel a glossy finish. Rice that is processed to remove only the husks, called brown rice, contains about 8 percent protein and small amounts of fats and is a source of thiamine, niacin, riboflavin, iron, and calcium. Rice that is milled to remove the bran as well is called white rice and is greatly diminished in nutrients. When white rice forms a major portion of the diet, there is a risk of beriberi, a disease resulting from a deficiency of thiamine and minerals. Parboiled white rice is specially processed before milling to retain most of the nutrients, and enriched rice has iron and B vitamins added to it.

    The milling methods used in most of Asia remain fairly primitive, but large mills operate in Japan and some other areas. Hulling of the paddy is usually accomplished by pestle and mortar worked by hand, foot, or water power. Improvements are slowly taking place. The yield of milled rice is dependent on the size and shape of the grain, the degree of ripeness, and the extent of exposure to the sun. Some large mills, handling 500 to 1,000 tons of paddy daily, have specialized hulling plants with consequent smaller losses from broken grain. They generally employ modern milling techniques and rely on controlled drying plants instead of on sun drying.

    • The Editors of Encyclopaedia Britannica
  4. en.wikipedia.org › wiki › RiceRice - Wikipedia

    Rice is the seed of the grass species Oryza sativa (Asian rice)—or, much less commonly, Oryza glaberrima (African rice). Asian rice was domesticated in China some 13,500 to 8,200 years ago; African rice was domesticated in Africa about 3,000 years ago.

  5. Oct 29, 2014 · In the 1960s and 1970s an influential Taiwanese agriculture scientist, the late Te-Tzu Chang, collected and cultivated wild rice from across Asia and proposed a band of domestication that...

    • Ewen Callaway
    • 2014
  6. In our first attempt to translate archaeological evidence for rice into a model of land area under wet rice that produced methane in the past, we found the the rice in wet rice area between 3000 BC and 1000 AD paralleled the increase in methane recorded from the greenland ice core (Grip 2).

  7. Archaeologists and botanists have long debated the origins of rice. For many archaeologists who focus on East Asia or Southeast Asia, it has long appeared that rice agriculture began in South-central China, somewhere along the Yangzte river, and spread from there southwards and to northeast towards Korea and Japan.

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