oryza sativa

O. sativa has an erect stalk stem that grows {{cvt|80|-|120|cm|round=5}} tall, with a smooth surface. The leaf is lanceolate, {{cvt|15|-|30|cm|frac=8}} long, and grows from a ligule {{cvt|10|-|20|mm|frac=8}} long.{{cite web |last1=Catindig |first1=J.L.A. |last2=Lubigan |first2=R.T. |last3=Johnson |first3=D. |date=n.d. |title=Oryza sativa |url=http://www.knowledgebank.irri.org/training/fact-sheets/item/oryza-sativa |website=Rice Knowledge Bank |publisher=International Rice Research Institute |access-date=29 June 2023}}

Image:Kerbau Jawa.jpg|Water buffalo ploughing a rice paddyfield, Java

File:Jumli Marshi Oryza sativa Rice.jpg|Jumli Marshi, brown rice from Nepal

File:Niyamgiri rice.jpg|Traditional rice of Niyamgiri Hills, India

File:Medicinal Rice.jpg|From Chhattisgarh

File:Koeh-232.jpg|

File:RiceStemcs400x1.jpg|Stem cross section magnified 400 times

{{see also|History of rice cultivation|List of rice varieties}}

The generic name Oryza{{cite Merriam-Webster|oryza}} is a classical Latin word for rice, while the specific epithet sativa means "cultivated".{{cite Lexico|sativa}}{{cite Merriam-Webster|sativa}}

Oryza sativa contains two major subspecies: the sticky, short-grained japonica or sinica variety, and the nonsticky, long-grained {{visible anchor |indica}} rice variety. Japonica was domesticated in the Yangtze Valley 6,000–9,000 years ago,{{cite journal |last1=Purugganan |first1=Michael D. |last2=Fuller |first2=Dorian Q. |title=The nature of selection during plant domestication |journal=Nature |publisher=Nature Research |volume=457 |issue=7231 |year=2009 |issn=0028-0836 |doi=10.1038/nature07895 |pages=843–848 |pmid=19212403 |bibcode=2009Natur.457..843P |s2cid=205216444 }} and its varieties can be cultivated in dry fields (it is cultivated mainly submerged in Japan), in temperate East Asia, upland areas of Southeast Asia, and high elevations in South Asia, while indica was domesticated around the Ganges 4,500–8,500 years ago, and its varieties are mainly lowland rices, grown mostly submerged, throughout tropical Asia. Rice grain occurs in a variety of colors, including white, brown, black (purple when cooked), and red.Oka (1988){{cite journal |last1=Mohammadi Shad |first1=Z. |last2=Atungulu |first2=G. |title=Post-harvest kernel discoloration and fungi activity in long-grain hybrid, pureline and medium-grain rice cultivars as influenced by storage environment and antifungal treatment |journal=Journal of Stored Products Research |date=March 2019 |volume=81 |pages=91–99 |doi=10.1016/j.jspr.2019.02.002 |s2cid=92050510 |doi-access=free}}

A third subspecies, which is broad-grained and thrives under tropical conditions, was identified based on morphology and initially called javanica, but is now known as tropical japonica. Examples of this variety include the medium-grain 'Tinawon' and 'Unoy' cultivars, which are grown in the high-elevation rice terraces of the Central Cordillera Mountains of northern Luzon, Philippines.CECAP, PhilRice and IIRR. 2000. "Highland Rice Production in the Philippine Cordillera."

Glaszmann (1987) used isozymes to sort O. sativa into six groups: japonica, aromatic, indica, aus, rayada, and ashina.{{cite journal |last1=Glaszmann |first1=J. C. |title=Isozymes and classification of Asian rice varieties |journal=Theoretical and Applied Genetics |date=May 1987 |volume=74 |issue=1 |pages=21–30 |doi=10.1007/BF00290078 |pmid=24241451 |s2cid=22829122}}

Garris et al. (2004) used simple sequence repeats to sort O. sativa into five groups: temperate japonica, tropical japonica and aromatic comprise the japonica varieties, while indica and aus comprise the indica varieties.{{cite journal |last1=Garris |first1=Amanda J. |last2=Tai |first2=T. H. |last3=Coburn |first3=J. |last4=Kresovich |first4=S. |last5=McCouch |first5=S. |author5-link=Susan McCouch |year=2004 |title=Genetic structure and diversity in Oryza sativa L. |journal=Genetics |pmid=15654106 |doi=10.1534/genetics.104.035642 |volume=169 |issue=3 |pages=1631–1638 |pmc=1449546}} The Garris scheme has held up against newer analyses as of 2019,{{cite journal |last1=Civáň |first1=Peter |last2=Ali |first2=Sajid |last3=Batista-Navarro |first3=Riza |last4=Drosou |first4=Konstantina |last5=Ihejieto |first5=Chioma |last6=Chakraborty |first6=Debarati |last7=Ray |first7=Avik |last8=Gladieux |first8=Pierre |last9=Brown |first9=Terence A |title=Origin of the Aromatic Group of Cultivated Rice ( Oryza sativa L.) Traced to the Indian Subcontinent |journal=Genome Biology and Evolution |date=2019-03-01 |volume=11 |issue=3 |pages=832–843 |doi=10.1093/gbe/evz039|pmid=30793171 |pmc=6427689 }} though one 2014 article argues that rayada is distinct enough to be its own group under japonica.{{cite journal |last1=Wang |first1=C-H |last2=Zheng |first2=X-M |last3=Xu |first3=Q |last4=Yuan |first4=X-P |last5=Huang |first5=L |last6=Zhou |first6=H-F |last7=Wei |first7=X-H |last8=Ge |first8=S |title=Genetic diversity and classification of Oryza sativa with emphasis on Chinese rice germplasm |journal=Heredity |date=May 2014 |volume=112 |issue=5 |pages=489–496 |doi=10.1038/hdy.2013.130|pmid=24326293 |pmc=3998783 |bibcode=2014Hered.112..489W }}

{{visible anchor|SPL14}}/{{visible anchor|LOC4345998}} is a gene that regulates the overall architecture/growth habit of the plant. Some of its epialleles increase rice yield.{{cite journal |last1=Stange |first1=Madlen |last2=Barrett |first2=Rowan D. H. |last3=Hendry |first3=Andrew P. |title=The importance of genomic variation for biodiversity, ecosystems and people |journal=Nature Reviews Genetics |publisher=Nature Portfolio |volume=22 |issue=2 |date=February 2021 |issn=1471-0056 |doi=10.1038/s41576-020-00288-7 |pages=89–105 |pmid=33067582 |s2cid=223559538|id=MS ORCID [http://orcid.org/0000-0002-4559-2535 0000-0002-4559-2535]). (RDHB ORCID [http://orcid.org/0000-0003-3044-2531 0000-0003-3044-2531])}} An accurate and usable simple sequence repeat marker set was developed and used to generate a high-density map. A multiplex high-throughput marker assisted selection system has been developed but as with other crop HTMAS systems has proven difficult to customize, costly (both directly and for the equipment), and inflexible.{{cite journal|publisher=Elsevier|last1=Rasheed |first1=Awais |last2=Hao |first2=Yuanfeng |last3=Xia |first3=Xianchun |last4=Khan |first4=Awais |last5=Xu |first5=Yunbi |last6=Varshney |first6=Rajeev K. |last7=He |first7=Zhonghu |title=Crop Breeding Chips and Genotyping Platforms: Progress, Challenges, and Perspectives |journal=Molecular Plant|id=Chinese Academy of Sciences+Chinese Society for Plant Biology+Shanghai Institutes for Biological Sciences|volume=10|issue=8|year=2017 |issn=1674-2052 |doi=10.1016/j.molp.2017.06.008 |pages=1047–1064 |s2cid=33780984 |pmid=28669791|doi-access=free |bibcode=2017MPlan..10.1047R }} Other molecular breeding tools have produced rice blast resistant cultivars.{{cite journal |last1=Miah |first1=G. |last2=Rafii |first2=M. Y. |last3=Ismail |first3=M. R. |last4=Puteh |first4=A. B. |last5=Rahim |first5=H. A. |last6=Asfaliza |first6=R. |last7=Latif |first7=M. A. |title=Blast resistance in rice: a review of conventional breeding to molecular approaches |journal=Molecular Biology Reports |publisher=Springer Science+Business Media |volume=40 |issue=3 |date=2012-11-27 |issn=0301-4851 |doi=10.1007/s11033-012-2318-0 |pages=2369–2388|pmid=23184051 |s2cid=8922855 |url=http://psasir.upm.edu.my/id/eprint/29230/1/29230.pdf }}{{cite journal |last1=Rao |first1=Yuchun |last2=Li |first2=Yuanyuan |last3=Qian |first3=Qian |title=Recent progress on molecular breeding of rice in China |journal=Plant Cell Reports |publisher=Springer Science+Business Media |volume=33 |issue=4 |date=2014-01-19 |issn=0721-7714 |doi=10.1007/s00299-013-1551-x |pages=551–564|pmid=24442397 |pmc=3976512 |bibcode=2014PCelR..33..551R }} DNA microarray has been used to advance understanding of hybrid vigor in rice, QTL sequencing has been used to elucidate seedling vigor, and genome wide association study (GWAS) by whole genome sequencing (WGS) has been used to investigate various agronomic traits.

In total, 641 copy number variations are known. Exome capture often reveals new single nucleotide polymorphisms in rice, due to its large genome and high degree of DNA repetition.

Resistance to the rice blast fungus Magnaporthe grisea is provided by various resistance genes including {{visible anchor|Pi1}}, {{visible anchor|Pi54}}, and {{visible anchor|Pita}}.{{cite book |editor-last=Wani |editor-first=Shabir Hussain |title=Disease Resistance in Crop Plants: Molecular, Genetic and Genomic Perspectives |publisher=Springer |year=2019 |isbn=978-3-030-20727-4 |oclc=1110184027 |pages=83–112/xii+307 |chapter=5 Rice, Marker-Assisted Breeding, and Disease Resistance |last1=Mehta |first1=Sahil |last2=Singh |first2=Baljinder |last3=Dhakate |first3=Priyanka |last4=Rahman |first4=Mehzabin |last5=Islam |first5=Muhammad Aminul}} O. sativa uses the plant hormones abscisic acid and salicylic acid to regulate immune responses. Salicylic acid broadly stimulates, and abscisic acid suppresses, immunity to M. grisea; success depends on the balance between their levels.{{cite journal |last1=Pieterse |first1=Corné M.J. |last2=Van der Does |first2=Dieuwertje |last3=Zamioudis |first3=Christos |last4=Leon-Reyes |first4=Antonio |last5=Van Wees |first5=Saskia C.M. |title=Hormonal Modulation of Plant Immunity |journal=Annual Review of Cell and Developmental Biology |publisher=Annual Reviews |volume=28 |issue=1 |date=2012-11-10 |issn=1081-0706 |doi=10.1146/annurev-cellbio-092910-154055 |pages=489–521 |s2cid=18180536 |pmid=22559264|hdl=1874/274421 |url=https://dspace.library.uu.nl/handle/1874/274421 |ref=none}}

|{{cite journal|publisher=Oxford University Press |last1=Atkinson |first1=Nicky J. |last2=Urwin |first2=Peter E. |title=The interaction of plant biotic and abiotic stresses: from genes to the field |journal=Journal of Experimental Botany |volume=63 |issue=10 |date=2012-03-30 |issn=0022-0957 |doi=10.1093/jxb/ers100 |pages=3523–3543 |s2cid=205195661 |pmid=22467407|doi-access=free}}{{cite journal |last1=Liu |first1=Wende |last2=Liu |first2=Jinling |last3=Triplett |first3=Lindsay |last4=Leach |first4=Jan E. |last5=Wang |first5=Guo-Liang |title=Novel Insights into Rice Innate Immunity Against Bacterial and Fungal Pathogens |journal=Annual Review of Phytopathology |publisher=Annual Reviews |volume=52 |issue=1 |date=2014-08-04 |issn=0066-4286 |doi=10.1146/annurev-phyto-102313-045926 |pages=213–241 |s2cid=9244874 |pmid=21380629|bibcode=2014AnRvP..52..213L }}

O. sativa has a large number of insect resistance genes specifically for the brown planthopper.{{cite journal |last1=Wang |first1=Changsheng |last2=Han |first2=Bin |title=Twenty years of rice genomics research: From sequencing and functional genomics to quantitative genomics |journal=Molecular Plant |publisher=Cell Press |volume=15 |issue=4 |year=2022 |issn=1674-2052 |doi=10.1016/j.molp.2022.03.009 |pmid=35331914 |pages=593–619|s2cid=247603925 |doi-access=free |bibcode=2022MPlan..15..593W }} {{As of|2022}}, 15 R genes have been cloned and characterized.

• Domesticated plants and animals of Austronesia
• International Code of Nomenclature for Cultivated Plants
• Traceability of genetically modified organisms

{{reflist|30em}}

• {{Wikispecies-inline|Oryza sativa}}
• {{Commons category-inline|Oryza sativa}}

{{Rice}}

{{Taxonbar|from=Q161426}}

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sativa

Category:Crops originating from Asia

Category:Flora of China

Category:Plants described in 1753

Category:Rice

Category:Taxa named by Carl Linnaeus