''Oryza'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of plants in the

grass family Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns and ...

. It includes the major food crop

rice Rice is the seed of the grass species ''Oryza sativa'' (Asian rice) or less commonly ''Oryza glaberrima ''Oryza glaberrima'', commonly known as African rice, is one of the two domesticated rice species. It was first domesticated and grown i ...

(species ''

Oryza sativa ''Oryza sativa'', commonly known as Asian rice or indica 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 Yan ...

'' and ''

Oryza glaberrima ''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 In agriculture, it has largely been replaced by higher-yielding Asian ri ...

''). Members of the genus grow as tall,

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

grasses, growing to tall; the genus includes both

annual Annual may refer to: * Annual publication, periodical publications appearing regularly once per year **Yearbook ** Literary annual * Annual plant * Annual report * Annual giving * Annual, Morocco, a settlement in northeastern Morocco * Annuals (b ...

and

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

species. ''Oryza'' is situated in tribe

Oryzeae Oryzeae is a tribe of flowering plants in the true grass family, Poaceae. It contains 11 genera, including both cultivated rice (''Oryza'') and wild rice Wild rice, also called manoomin, Canada rice, Indian rice, or water oats, is any of ...

, which is characterized morphologically by its single-flowered spikelets whose

glumes In botany, a glume is a bract (leaf-like structure) below a spikelet in the inflorescence (flower cluster) of grasses (Poaceae) or the flowers of sedges (Cyperaceae). There are two other types of bracts in the spikelets of grasses: the lemma and ...

are almost completely suppressed. In ''Oryza'', two sterile

lemma Lemma may refer to: Language and linguistics * Lemma (morphology), the canonical, dictionary or citation form of a word * Lemma (psycholinguistics), a mental abstraction of a word about to be uttered Science and mathematics * Lemma (botany), a ...

simulate glumes. The tribe Oryzeae is in subfamily Ehrhartoideae, a group of Poaceae tribes with certain features of internal leaf anatomy in common. The most distinctive leaf characteristics of this subfamily are the arm cells and fusoid cells found in their leaves.Heywood, V.H. Flowering Plants of the World 1993 Oxford University Press One species, Asian rice ( ''O. sativa''), provides 20% of global grain and is a food crop of major global importance. The species are divided into two subgroups within the genus.

Species

Inside the genus ''Oryza'', species can be divided by their genomes types. They include the

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...

(2n = 24) of cultivated rice and their relatives, , , , and as well as the

tetraploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

(4n = 48) , , , and . Species of the same genome type cross easily, while hybridizing different types requires techniques like

embryo rescue Embryo rescue is one of the earliest and successful forms of in-vitro culture techniques that is used to assist in the development of plant embryos that might not survive to become viable plants. Embryo rescue plays an important role in modern plan ...

. Over 300 names have been proposed for species, subspecies, and other infraspecific taxa within the genus. Published sources disagree as to how many of these should be recognized as distinct species. The following follows the World Checklist maintained by Kew Garden in London. * ''

Oryza australiensis ''Oryza australiensis'' is a wild rice species native to northern Australia. It is a perennial plant that uses the C3 photosynthesis carbon fixation is the most common of three metabolic pathways for carbon fixation in photosynthesis, along ...

'' (EE) – Australia * ''

Oryza barthii ''Oryza barthii'', also called Barth's rice, wild rice, or African wild rice, is a grass in the rice genus ''Oryza''. It is an annual, erect to semierect grass. It has leaves with a short ligule (<), and panicles that are compact to open, rarely ...

'' (AA) – tropical Africa * ''

Oryza brachyantha ''Oryza brachyantha'' is a grass in the rice genus ''Oryza ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetlan ...

'' (FF) – tropical Africa * ''

Oryza coarctata ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (KKLL) – India, Pakistan, Bangladesh, Myanmar * ''

Oryza eichingeri ''Oryza eichingeri'' (syns. ''Oryza collina'' and ''Oryza rhizomatis'') is a species of wild rice in the family Poaceae, with a disjunct distribution in Ivory Coast, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Tanzania ...

'' (CC) – tropical Africa, Sri Lanka * ''

'' (AA) – African rice – tropical Africa * ''

Oryza grandiglumis ''Oryza grandiglumis'' is a type of wild rice of the genus ''Oryza'' found in tropical countries of South- and Central- America, namely Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Paraguay, Venezuela, and Peru. Discovered in 1 ...

'' (CCDD) – Brazil, Venezuela, Fr Guiana, Colombia, Peru, Bolivia * ''

Oryza latifolia ''Oryza latifolia'', the broadleaf rice, is a widespread species of grass (family Poaceae Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the ce ...

'' (CCDD) – Latin America + West Indies from Sinaloa + Cuba to Argentina * ''

Oryza longiglumis ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (HHJJ) – New Guinea * ''

Oryza longistaminata ''Oryza longistaminata'' is a perennial species of grass from the same genus as cultivated rice (''O. sativa''). It is native to most of sub-Saharan Africa and Madagascar. It has been introduced into the United States, where it is often regarded ...

'' (AA) – Madagascar, tropical + southern Africa * ''

Oryza meyeriana ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (GG) – China, Indian Subcontinent, Southeast Asia * ''

Oryza minuta ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (BBCC) – Himalayas, Southeast Asia, New Guinea, Northern Territory of Australia * ''

Oryza neocaledonica ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (GG) – New Caledonia * ''

Oryza officinalis ''Oryza officinalis'' is species of flowering plant in the genus ''Oryza'' (rice) native to India, Nepal, the eastern Himalaya, southeast Asia, south-central and southeast China, Hainan, the Philippines, New Guinea, and the Northern Territory and ...

'' (CC) – China, Indian Subcontinent, Southeast Asia, New Guinea, Australia * ''

Oryza punctata ''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.Ibrahim, K.M. and Kabuye, C.H.S. (1987). An ...

'' (BB) – Madagascar, tropical + southern Africa * ''

Oryza ridleyi ''Oryza'' is a genus of plants in the grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both annual an ...

'' (HHJJ) – Southeast Asia, New Guinea * ''

Oryza rufipogon ''Oryza rufipogon'', known as brownbeard rice, wild rice, and red rice, is a member of the genus ''Oryza''. It is native to East, Southeast and South Asia. It has a close evolutionary relation to ''Oryza sativa'', the plant grown as a major rice ...

'' (AA) – brownbeard or red rice – China, Indian Subcontinent, Southeast Asia, New Guinea, Australia * ''

'' (AA) – Asian rice – China, Indian Subcontinent, Japan, Southeast Asia; naturalized many places * ''

Oryza schlechteri ''Oryza'' is a genus of plants in the Poaceae, grass family. It includes the major food crop rice (species ''Oryza sativa'' and ''Oryza glaberrima''). Members of the genus grow as tall, wetland grasses, growing to tall; the genus includes both A ...

'' (HHKK) – New Guinea

Formerly included

Many species now regarded as better suited to other genera: *

Echinochloa ''Echinochloa'' is a very widespread genus of plants in the grass family and tribe Paniceae. Some of the species are known by the common names barnyard grass or cockspur grass. Some of the species within this genus are millets that are grown a ...

Leersia ''Leersia'' is a genus of plants in the grass family which includes species known generally as cutgrasses. The genus is widespread across many countries on all the inhabited continents. It was named for the German botanist Johann Daniel Leers ...

Maltebrunia ''Maltebrunia'' is a genus of African plants in the Poaceae, grass family. ; Species * ''Maltebrunia leersioides'' Kunth – Madagascar * ''Maltebrunia letestui'' (Koechlin) Koechlin – Cameroon, Gabon, Republic of the CongoHubbard, C. E. 1962. ...

Potamophila ''Potamophila'' is a genus of Australian plants in the grass family. The only known species is ''Potamophila parviflora''.Ge, S., et al. (2002)A phylogeny of the rice tribe Oryzeae (Poaceae) based on matK sequence data.''American Journal of B ...

Prosphytochloa ''Prosphytochloa'' is a genus of African plants in the grass family. The only known species is ''Prosphytochloa prehensilis'', native to Eastern Cape Province, KwaZulu-Natal, Eswatini, Mpumalanga, and Limpopo Limpopo is the northernmos ...

Rhynchoryza ''Rhynchoryza'' is a genus of plants in the grass family.Rosengurtt, B., B. R. A. Maffei & P. I. Artucio. 1970. Gramíneas Uruguayas –vii 1–489. Universidad de la República, Montevideo The only known species is ''Rhynchoryza subulata'', na ...

References

Poaceae genera Taxa named by Carl Linnaeus {{Poaceae-stub

Species

Formerly included

See also

References