Rice is a cereal grain, and in its domesticated form is the staple food for over half of the world's human population, particularly in Asia and Africa, due to the vast amount of soil that is able to grow rice. Rice is the seed of the grass species Oryza sativa or, much less commonly, O. glaberrima. Asian rice was domesticated in China some 13,500 to 8,200 years ago, while African rice was domesticated in Africa some 3,000 years ago. Rice has become commonplace in many cultures worldwide; in 2021, 787 million tons were produced, placing it fourth after sugarcane, maize, and wheat. Only some 8% of rice is traded internationally. China, India, and Indonesia are the largest consumers of rice. A substantial amount of the rice produced in developing nations is lost after harvest through factors such as poor transport and storage. Rice yields can be reduced by pests including insects, rodents, and birds, as well as by weeds, and by diseases such as rice blast. Traditional polycultures such as rice-duck farming, and modern integrated pest management seek to control damage from pests in a sustainable way.
Oryza is a genus of plants in the grass family. It includes the major food crop rice. Members of the genus grow as tall, wetland grasses, growing to 1–2 metres (3–7 ft) tall; the genus includes both annual and perennial species.
Oryza sativa, also known as rice, is the plant species most commonly referred to in English as rice. It is the type of farmed rice whose cultivars are most common globally, and was first domesticated in the Yangtze River basin in China 13,500 to 8,200 years ago.
Perennial sunflower is a crop of sunflowers that are developed by crossing wild perennial and domestic annual sunflower species.
Hybrid rice is a type of Asian rice that has been crossbred from two very different parent varieties. As with other types of hybrids, hybrid rice typically displays heterosis or "hybrid vigor", so when grown under the same conditions as comparable purebred rice varieties, it can produce up to 30% more yield. To produce hybrid seeds in large quantity, a purebred sterile rice variety is fertilized with fertile pollen from a different variety. High-yield crops, including hybrid rice, are one of the most important tools for combatting worldwide food crises.
Intensive crop farming is a modern industrialized form of crop farming. Intensive crop farming's methods include innovation in agricultural machinery, farming methods, genetic engineering technology, techniques for achieving economies of scale in production, the creation of new markets for consumption, patent protection of genetic information, and global trade. These methods are widespread in developed nations.
Oryza rufipogon, known as brownbeard rice, wild rice, and red rice, is a member of the genus Oryza.
Oryza longistaminata is a perennial species of grass from the same genus as cultivated rice. It is native to most of sub-Saharan Africa and Madagascar. It has been introduced into the United States, where it is often regarded as a noxious weed. Its common names are longstamen rice and red rice.
A crop wild relative (CWR) is a wild plant closely related to a domesticated plant. It may be a wild ancestor of the domesticated (cultivated) plant or another closely related taxon.
Upland rice is a variety of rice grown on dry soil rather than flooded rice paddies.
Oryza glaberrima, commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown in West Africa around 3,000 years ago. In agriculture, it has largely been replaced by higher-yielding Asian rice, and the number of varieties grown is declining. It still persists, making up an estimated 20% of rice grown in West Africa. It is now rarely sold in West African markets, having been replaced by Asian strains.
Thinopyrum intermedium, known commonly as intermediate wheatgrass, is a sod-forming perennial grass in the Triticeae tribe of Pooideae native to Europe and Western Asia. It is part of a group of plants commonly called wheatgrasses because of the similarity of their seed heads or ears to common wheat. However, wheatgrasses generally are perennial, while wheat is an annual. It has gained the Royal Horticultural Society's Award of Garden Merit as an ornamental.
Rice production in China is the amount of rice planted, grown, and harvested for consumption in the mainland of China.
Striga hermonthica, commonly known as purple witchweed or giant witchweed, is a hemiparasitic plant that belongs to the family Orobanchaceae. It is devastating to major crops such as sorghum and rice. In sub-Saharan Africa, apart from sorghum and rice, it also infests maize, pearl millet, and sugar cane.
A perennial grain is a grain crop that lives and remains productive for two or more years, rather than growing for only one season before harvest, like most grains and annual crops. While many fruit, nut and forage crops are long-lived perennial plants, all major grain crops presently used in large-scale agriculture are annuals or short-lived perennials grown as annuals. Scientists from several nations have argued that perennial versions of today's grain crops could be developed and that these perennial grains could make grain agriculture more sustainable.
Perennial crops are a perennial plant species that are cultivated and live longer than two years without the need of being replanted each year. Naturally perennial crops include many fruit and nut crops; some herbs and vegetables also qualify as perennial. Perennial crops have been cultivated for thousands of years; their cultivation differs from the mainstream annual agriculture because regular tilling is not required and this results in decreased soil erosion and increased soil health. Some perennial plants that are not cultivated as perennial crops are tomatoes, whose vines can live for several years but often freeze and die in winters outside of temperate climates, and potatoes which can live for more than two years but are usually harvested yearly. Despite making up 94% of plants on earth, perennials take up only 13% of global cropland. In contrast, grain crops take up about 70% of global cropland and global caloric consumption and are largely annual plants.
Plant breeding started with sedentary agriculture, particularly the domestication of the first agricultural plants, a practice which is estimated to date back 9,000 to 11,000 years. Initially, early human farmers selected food plants with particular desirable characteristics and used these as a seed source for subsequent generations, resulting in an accumulation of characteristics over time. In time however, experiments began with deliberate hybridization, the science and understanding of which was greatly enhanced by the work of Gregor Mendel. Mendel's work ultimately led to the new science of genetics. Modern plant breeding is applied genetics, but its scientific basis is broader, covering molecular biology, cytology, systematics, physiology, pathology, entomology, chemistry, and statistics (biometrics). It has also developed its own technology. Plant breeding efforts are divided into a number of different historical landmarks.
Oryza punctata is an annual grass in the rice genus Oryza, also known as red rice, related to cultivated rice O. sativa. O. punctata forms clumps or tussocks from 50–120 cm tall. It is a native to tropical Africa and Madagascar but is also found in Thailand and other parts of Indochina. O. punctata is a weed species in commercial rice growing operations although it appears to be rare in its native range. O. punctata has an IUCN status of least concern. It is not generally eaten or used as fodder by farmers but there is some evidence that it has been used as such during periods of famine. Due to the importance of the crop varieties of rice globally, the evolution of the Oryza genus as a whole has been studied extensively. A lot of information about O. punctata has been elucidated as a secondary benefit to this commercial research. O. punctata evolved some 5 million years ago in the second of two rapid radiation events that occurred in the Oryza L. genus.
Dilbagh Singh Athwal was an Indian-American geneticist, plant breeder and agriculturist, known to have conducted pioneering research in plant breeding. He was a professor and the Head of the Department of Plant Breeding at Punjab Agricultural University and an associate of Norman Borlaug, a renowned biologist and Nobel Laureate, with whom he has collaborated for the introduction of high-yielding dwarf varieties of wheat.
The agricultural weed syndrome is the set of common traits which make a plant a successful agricultural weed. Most of these traits are not, themselves, phenotypes but are instead methods of rapid adaptation. So equipped, plants of various origins - invasives, natives, mildly successful marginal weeds of agriculture, weeds of other settings - accumulate other characteristics which allow them to compete in an environment with a high degree of human management.
