GetWiki

{{good article}}{{Short description|Cereal (Oryza sativa)}}{{Other uses}}{{pp-vandalism|small=yes}}{{pp-move-indef}}{{Use mdy dates|date=April 2024}}File:20201102.Hengnan.Hybrid rice Sanyou-1.6.jpg|thumb|upright=1.35|Rice plant (Oryza sativa) with branched paniclepanicleFile:Rice grains (IRRI).jpg|thumb|upright=1.35|Rice grains of different varieties at the International Rice Research InstituteInternational Rice Research InstituteRice 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 (Asian rice) or, much less commonly, O. glaberrima (African rice). 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 rice polycultures such as rice-duck farming, and modern integrated pest management seek to control damage from pests in a sustainable way. Many varieties of rice have been bred to improve crop quality and productivity. Biotechnology has created Green Revolution rice able to produce high yields when supplied with nitrogen fertilizer and managed intensively. Other products are rice able to express human proteins for medicinal use; flood-tolerant or deepwater rice; and drought-tolerant and salt-tolerant varieties. Rice is used as a model organism in biology.Dry rice grain is milled to remove the outer layers; depending on how much is removed, products range from brown rice to rice with germ and white rice. Some is parboiled to make it easy to cook. Rice contains no gluten; it provides protein but not all the essential amino acids needed for good health. Rice of different types is eaten around the world. Long-grain rice tends to stay intact on cooking; medium-grain rice is stickier, and is used for sweet dishes, and in Italy for risotto; and sticky short-grain rice is used in Japanese sushi as it keeps its shape when cooked. White rice when cooked contains 29% carbohydrate and 2% protein, with some manganese. Golden rice is a variety produced by genetic engineering to contain vitamin A.Production of rice is estimated to have caused over 1% of global greenhouse gas emissions in 2022. Rice yields are predicted to fall by some 20% with each 1°C rise in global mean temperature. In human culture, rice plays a role in certain religions and traditions, such as in weddings.

Description

The rice plant can grow to over {{cvt|1|m|ft|0}} tall; if in deep water, it can reach a length of {{cvt|5|m|ft|0}}. A single plant may have several leafy stems or tillers. The upright stem is jointed with nodes along its length; a long slender leaf arises from each node.WEB, Oryza sativa L.,weblink Royal Botanic Gardens, Kew, December 6, 2023, The self-fertile flowers are produced in a panicle, a branched inflorescence which arises from the last internode on the stem. There can be up to 350 spikelets in a panicle, each containing male and female flower parts (anthers and ovule). A fertilised ovule develops into the edible grain or caryopsis.WEB, The Rice Plant,weblink Rice Hub, December 6, 2023, Rice is a cereal belonging to the family Poaceae. As a tropical crop, it can be grown during the two distinct seasons (dry and wet) of the year provided that sufficient water is made available.JOURNAL, Kawure, S., Garba, Aa, Fagam, As, Shuaibu, Ym, Sabo, Mu, Bala, Ra, December 31, 2022, Performance of Lowland Rice (Oryza sativa L.) as Influenced by Combine Effect of Season and Sowing Pattern in Zigau,weblink Journal of Rice Research and Developments, 5, 2, 10.36959/973/440, 256799161, free, It is normally an annual, but in the tropics it can survive as a perennial, producing a ratoon crop.WEB,weblink The Rice Plant and How it Grows, International Rice Research Institute,weblink" title="web.archive.org/web/20090106224427weblink">weblink January 6, 2009, File:Koeh-232.jpg|Anatomy of rice flowers: spikelet (left), plant with tillers (centre), caryopsis (top right), panicle (right)File:Oryza sativa of Kadavoor.jpg|Detail of rice plant showing flowers grouped in panicle. Male anthers protrude into the air where they can disperse their pollen.

Agronomy

Growing

Like all crops, rice depends for its growth on both biotic and abiotic environmental factors. The principal biotic factors are crop variety, pests, and plant diseases. Abiotic factors include the soil type, whether lowland or upland, amount of rain or irrigation water, temperature, day length, and intensity of sunlight.BOOK, Beighley, Donn H., Soils, Plant Growth and Crop Production Volume II, Growth and Production of Rice, Verheye, Willy H., 2010, EOLSS Publishers, 978-1-84826-368-0,weblink 49, Rice grains can be planted directly into the field where they will grow, or seedlings can be grown in a seedbed and transplanted into the field. Direct seeding needs some 60 to 80 kg of grain per hectare, while transplanting needs less, around 40 kg per hectare, but requires far more labour.WEB,weblink How to plant rice, International Rice Research Institute, December 29, 2023, Most rice in Asia is transplanted by hand. Mechanical transplanting takes less time but requires a carefully-prepared field and seedlings raised on mats or in trays to fit the machine.WEB,weblink Transplanting, International Rice Research Institute, December 29, 2023, Rice does not thrive if continuously submerged.WEB, Uphoff, Norman,weblink More rice with less water through SRI - the System of Rice Intensification, Cornell University,weblink December 26, 2011, May 13, 2012, Rice can be grown in different environments, depending upon water availability. The usual arrangement is for lowland fields to be surrounded by bunds and flooded to a depth of a few centimetres until around a week before harvest time; this requires a large amount of water. The "alternate wetting and drying" technique uses less water. One form of this is to flood the field to a depth of 5 cm (2 in), then to let the water level drop to 15 cm (6 in) below surface level, as measured by looking into a perforated field water tube sunk into the soil, and then repeating the cycle.WEB,weblink Water Management, International Rice Research Institute, November 4, 2023, Deepwater rice varieties tolerate flooding to a depth of over 50 centimetres for at least a month.BOOK, Catling, David, Deepwater Rice Cultures in the Ganges-Brahmaputra Basin, Rice in Deep Water, International Rice Research Institute, 1992,weblink 978-971-22-0005-2, 2, Upland rice is grown without flooding, in hilly or mountainous regions; it is rainfed like wheat or maize.BOOK, Gupta, Phool Chand, O'Toole, J. C. O'Toole, 1986, Upland Rice: A Global Perspective, International Rice Research Institute, 978-971-10-4172-4, File:Kerbau Jawa.jpg|Ploughing a rice terrace with water buffaloes, JavaFile:Cambodian farmers planting rice.jpg|Farmers planting rice by hand in Cambodia File:Rice-planting-machine 2,katori-city,japan.JPG|Mechanised rice planting in JapanFile:Pana Banaue Rice Terraces (Cropped).jpg|Ancient mountainside rice terraces at Banaue, Philippines

Harvesting

Across Asia, unmilled rice or "paddy" (Indonesian and Malay ), was traditionally the product of smallholder agriculture, with manual harvesting. Larger farms make use of machines such as combine harvesters to reduce the input of labour.WEB, Harvesting systems,weblink International Rice Research Institute, January 3, 2024, The grain is ready to harvest when the moisture content is 20–25%. Harvesting involves reaping, stacking the cut stalks, threshing to separate the grain, and cleaning by winnowing or screening.WEB, Harvesting,weblink International Rice Research Institute, December 6, 2023, The rice grain is dried as soon as possible to bring the moisture content down to a level that is safe from mould fungi. Traditional drying relies on the heat of the sun, with the grain spread out on mats or on pavements.WEB, Drying,weblink International Rice Research Institute, December 6, 2023, File:Rice-combine-harvester, Katori-city, Japan.jpg|Rice combine harvester in Chiba Prefecture, Japan File:Rice farmers Mae Wang Chiang Mai Province.jpg|After the harvest, rice straw is gathered in the traditional way from small paddy fields in Mae Wang District, ThailandFile:NP India burning 48 (6315309342).jpg|Burning of rice residues to prepare the land for wheat planting in Sangrur, IndiaFile:Nellu.JPG|Drying rice in Peravoor, India

Evolution

Phylogeny

{{further|Oryza sativa}}The edible rice species are members of the BOP clade within the grass family, the Poaceae. The rice subfamily, Oryzoideae, is sister to the bamboos, Bambusoideae, and the cereal subfamily Pooideae. The rice genus Oryza is one of eleven in the Oryzeae; it is sister to the Phyllorachideae. The edible rice species O. sativa and O. glaberrima are among some 300 species or subspecies in the genus.JOURNAL, Soreng, Robert J., Peterson, Paul M., Romaschenko, Konstantin, Davidse, Gerrit, Teisher, Jordan K., Clark, Lynn G., Barberá, Patricia, Gillespie, Lynn J., Zuloaga, Fernando O., A worldwide phylogenetic classification of the Poaceae (Gramineae) II: An update and a comparison of two 2015 classifications, Journal of Systematics and Evolution, 55, 4, 2017, 259–290, 1674-4918, 10.1111/jse.12262, free, 10261/240149, free, {{clade|label1=Poaceae|1={{clade }}{{Anchor|Domestication}}

History

File:KITLV_40091_-_Kassian_Céphas_-_Relief_of_the_hidden_base_of_Borobudur_-_1890-1891.jpg|thumb|upright=1.5|Bas-relief of 9th century Borobudur in Indonesia describes rice barnrice barnOryza sativa rice was first domesticated in the Yangtze River basin in China 13,500 to 8,200 years ago. The functional allele for nonshattering, the critical indicator of domestication in grains, as well as five other single-nucleotide polymorphisms, is identical in both indica and japonica. This implies a single domestication event for O. sativa. Both indica and japonica forms of Asian rice sprang from a single domestication event in China from the wild rice Oryza rufipogon.JOURNAL, Molina, J., Sikora, M., Garud, N., Flowers, J. M., Rubinstein, S., Reynolds, A., Huang, P., Jackson, S., Schaal, B. A., Bustamante, C. D., Boyko, A. R., 5, 2011, Molecular evidence for a single evolutionary origin of domesticated rice, Proceedings of the National Academy of Sciences, 108, 20, 8351–8356, 2011PNAS..108.8351M, 10.1073/pnas.1104686108, 3101000, 21536870, Purugganan, M. D., free, JOURNAL, Vaughan, D.A., Lu, B., Tomooka, N., 2008, The evolving story of rice evolution,weblink Plant Science, 174, 4, 394–408, 10.1016/j.plantsci.2008.01.016, March 29, 2021, September 24, 2020,weblink live, Despite this evidence, it appears that indica rice arose when japonica arrived in India about 4,500 years ago and hybridised with another rice, whether an undomesticated proto-indica or wild O. nivara.JOURNAL, Choi, Jae, etal, 2017, The Rice Paradox: Multiple Origins but Single Domestication in Asian Rice, Molecular Biology and Evolution, 34, 4, 969–979, 10.1093/molbev/msx049, 5400379, 28087768, Further, rice grains with signs of having been cut have been found alongside stone tools dated to 17,300 years ago at Sorori in Korea. This implies domestication in progress, far from the Yangtze River basin, at an earlier date.JOURNAL, Kim, Kyeong J., etal, Radiocarbon Ages of Suyanggae Paleolithic Sites in Danyang, Korea, Radiocarbon (journal), Radiocarbon, 63, 5, 2021, 1429–1444, 10.1017/RDC.2021.77, 2021Radcb..63.1429K, Cultivation, migration and trade spread rice around the world—first to much of east Asia, then further abroad, and eventually to the Americas as part of the Columbian exchange after 1492. The now less common Oryza glaberrima (African rice) was independently domesticated in Africa around 3,000 years ago,JOURNAL, Choi, Jae Young, March 7, 2019, The complex geography of domestication of the African rice Oryza glaberrima, PLOS Genetics, 15, 3, e1007414, 10.1371/journal.pgen.1007414, 6424484, 30845217, free, and introduced to the Americas by the Spanish.BOOK, National Research Council,weblink Lost Crops of Africa: Volume I: Grains, National Academies Press, 1996, 978-0-309-04990-0, 1, African Rice, 10.17226/2305, July 18, 2008,weblinkweblink" title="web.archive.org/web/20090122104044weblink">weblink January 22, 2009, live,

Commerce

{| class="wikitable" style="float:right; clear:right; width:14em; text-align:center; margin-right:1em;"! colspan=2|Rice production – 2021! style="background:#ddf; width:50%;"|Country! style="background:#ddf; width:50%;"| Millions of tonnes

	Rice production in China>213

	Rice production in India>195

	Rice production in Bangladesh>57

	Rice production in Indonesia>54

	Rice production in Vietnam>44

	Rice production in Thailand>30

World >	787HTTP://WWW.FAO.ORG/FAOSTAT/EN/#DATA/QC	DATE=2023	FAOSTAT, UN FOOD AND AGRICULTURE ORGANIZATION, CORPORATE STATISTICAL DATABASE >ACCESS-DATE=DECEMBER 4, 2023,

Production

In 2021, world production of rice was 787 million tonnes, led by China and India with a combined 52% of the total. This placed rice fourth in the list of crops by production, after sugarcane, maize, and wheat. Other major producers were Bangladesh, Indonesia and Vietnam. 90% of world production is from Asia.File:Production of rice (2019).svg|Production of rice (2021)BOOK, World Food and Agriculture – Statistical Yearbook 2021,weblink December 10, 2021, United Nations Food and Agriculture Organization, 2021, 10.4060/cb4477en, 978-92-5-134332-6, 240163091, File:World Production Of Primary Crops, Main Commodities.svg|Rice's share (orange) of world crop production fell in the 21st century.

Yield records

The average world yield for rice was {{convert|4.7|MT/ha|ST/acre|abbr=off}}, in 2022.WEB, FAOSTAT: Production-Crops, 2022 data, United Nations Food and Agriculture Organization, 2022,weblink Yuan Longping of China's National Hybrid Rice Research and Development Center set a world record for rice yield in 1999 at {{convert|17.1|MT/ha|ST/acre|abbr=off}} on a demonstration plot. This employed specially developed hybrid rice and the System of Rice Intensification (SRI), an innovation in rice farming.WEB, A Scientist's Perspective on Experience with SRI in China for Raising the Yields of Super Hybrid Rice, 2010, Yuan, Longping, Yuan Longping, Cornell University,weblink dead,weblink" title="web.archive.org/web/20111120010557weblink">weblink November 20, 2011,

Food security

Rice is a major food staple in Asia, Latin America, and some parts of Africa,WEB, Food Staple,weblink National Geographic Education, December 6, 2023, feeding over half the world's population.JOURNAL, Fukagawa, Naomi K., Ziska, Lewis H., Rice: Importance for Global Nutrition, Journal of Nutritional Science and Vitaminology, 65, Supplement, October 11, 2019, 0301-4800, 10.3177/jnsv.65.S2, S2–S3, 31619630, free, However, a substantial part of the crop can be lost post-harvest through inefficient transportation, storage, and milling. A quarter of the crop in Nigeria is lost after harvest. Storage losses include damage by mould fungi if the rice is not dried sufficiently. In China, losses in modern metal silos were just 0.2%, compared to 7–13% when rice was stored by rural households.JOURNAL, Kumar, Deepak, Kalita, Prasanta, Reducing Postharvest Losses during Storage of Grain Crops to Strengthen Food Security in Developing Countries, Foods, 6, 1, January 15, 2017, 2304-8158, 28231087, 5296677, 10.3390/foods6010008, free, 8,

Processing

The dry grain is milled to remove the outer layers, namely the husk and bran. These can be removed in a single step, in two steps, or as in commercial milling in a multi-step process of cleaning, dehusking, separation, polishing, grading, and weighing.WEB, Milling,weblink International Rice Research Institute, January 4, 2024, Brown rice only has the inedible husk removed. Further milling removes bran and the germ to create successively whiter products. Parboiled rice is subjected to a steaming process before it is milled. This makes the grain harder, and moves some of the grain's vitamins and minerals into the white part of the rice so these are retained after milling.WEB,weblink Types of rice, Rice Association, August 2, 2018,weblink" title="web.archive.org/web/20180802162740weblink">weblink August 2, 2018, dead, Rice does not contain gluten, so is suitable for people on a gluten-free diet.JOURNAL, Penagini, Francesca, Dilillo, Dario, Meneghin, Fabio, Mameli, Chiara, Fabiano, Valentina, Zuccotti, Gian, Gluten-Free Diet in Children: An Approach to a Nutritionally Adequate and Balanced Diet, Nutrients, MDPI AG, 5, 11, November 18, 2013, 2072-6643, 10.3390/nu5114553, 4553–4565, 24253052, 3847748, free, Rice is a good source of protein and a staple food in many parts of the world, but it is not a complete protein as it does not contain all of the essential amino acids in sufficient amounts for good health.JOURNAL, Wu, Jianguo G., Shi, Chunhai, Zhang, Xiaoming, Estimating the amino acid composition in milled rice by near-infrared reflectance spectroscopy, Field Crops Research, Elsevier BV, 75, 1, 2002, 0378-4290, 10.1016/s0378-4290(02)00006-0, 1–7, 2002FCrRe..75....1W, File:Rice Animation.gif|Rice processing removes one or more layers to create marketable products. A: Rice with chaffB: Brown riceC: Rice with germD: White rice with bran residueE: Polished(1): Chaff(2): Bran(3): Bran residue(4): Cereal germ(5): Endosperm File:Stages of rice milling.jpg|Unmilled to milled Japanese rice, from left to right, brown rice, rice with germ, white rice

Trade

World trade figures are much smaller than those for production, as less than 8% of rice produced is traded internationally. China, an exporter of rice in the early 2000s, had become the world's largest importer of rice by 2013.WEB, Cendrowski, Scott, July 25, 2013, The Rice Rush, Fortune,weblink January 4, 2024, Developing countries are the main players in the world rice trade; by 2012, India was the largest exporter of rice, with Thailand and Vietnam the other largest exporters.NEWS,weblink Chilkoti, A., India and the Price of Rice, Financial Times, London, October 30, 2012,weblink" title="web.archive.org/web/20130120052047weblink">weblink January 20, 2013,

Worldwide consumption

As of 2016, the countries that consumed the most rice were China (29% of total), India, and Indonesia.WEB, Global rice consumption continues to grow,weblink Grain Central, December 5, 2023, March 26, 2018, By 2020, Bangladesh had taken third place from Indonesia. On an annual average from 2020-23, China consumed 154 million tonnes of rice, India consumed 109 million tonnes, and Bangladesh and Indonesia consumed about 36 million tonnes each. Across the world, rice consumption per capita fell in the 21st century as people in Asia and elsewhere ate less grain and more meat. An exception is Sub-Saharan Africa, where both per capita consumption of rice and population are increasing.WEB, Rice Sector at a Glance,weblink Economic Research Service, US Department of Agriculture, December 5, 2023, September 27, 2023,

Food

factoids

Eating qualities

Rice is a commonly-eaten food around the world. The varieties of rice are typically classified as short-, medium-, and long-grained. Oryza sativa indica varieties are usually long-grained; Oryza sativa japonica varieties are usually short- or medium-grained. Short-grain rice, with the exception of Spanish Bomba, is usually sticky when cooked, and is suitable for puddings. Thai Jasmine rice is aromatic, and unusually for a long-grain rice has some stickiness, with a soft texture. Indian Basmati rice is very long-grained and aromatic.WEB, Indian Basmati Rice Exporter {{!, Best Basmati Rice |url=https://viexports.com/ |access-date=2024-05-14 |website=Vi Exports |language=en}} Italian Arborio rice, used for risotto, is of medium length, oval, and quite sticky. Japanese sushi rice is a sticky short-grain variety.WEB, Types of rice,weblink The Rice Association, March 24, 2024,

Nutrition

Cooked white rice is 69% water, 29% carbohydrates, 2% protein, and contains negligible fat (table). In a reference serving of {{convert|100|g}}, cooked white rice provides 130 calories of food energy, and contains moderate levels of manganese (18% DV), with no other micronutrients in significant content (all less than 10% of the Daily Value).WEB, FoodData Central: Rice, white, medium-grain, cooked, unenriched,weblink US Department of Agriculture, December 5, 2023, April 2018, In 2018, the World Health Organization strongly recommended fortifying rice with iron, and conditionally recommended fortifying it with vitamin A and with folic acid.BOOK, L. M., De-Regil, J. P., Peña-Rosas, A., Laillou, R., Moench-Pfanner, L. A., Mejia, A. M., Bower, S., de Pee, L. M., De-Regil, P. S., Suchdev, G. E., Vist, S., Walleser, J. P., Peña-Rosas, N. B., Piccoli, N., Grede, S., de Pee, A., Singhkumarwong, E., Roks, R., Moench-Pfanner, M. W., Bloem, 5, Guideline: Fortification of Rice with Vitamins and Minerals as a Public Health Strategy, World Health Organization, 2018, 30307723, 9789241550291,weblink December 5, 2023,

Golden rice

Golden rice is a variety produced through genetic engineering to synthesize beta-carotene, a precursor of vitamin A, in the endosperm of the rice grain. It is intended to be grown and eaten in parts of the world where Vitamin A deficiency is prevalent.WEB, Golden Rice Q&A,weblink Golden Rice Project, January 3, 2024, JOURNAL, Ye, Xudong, Al-Babili, Salim, Klöti, Andreas, Zhang, Jing, Lucca, Paola, Beyer, Peter, Potrykus, Ingo, Ingo Potrykus, Engineering the Provitamin A (β-Carotene) Biosynthetic Pathway into (Carotenoid-Free) Rice Endosperm, Science (journal), Science, 287, 5451, January 14, 2000, 0036-8075, 10.1126/science.287.5451.303, 303–305, 10634784, 2000Sci...287..303Y, 40258379, Golden rice has been opposed by activists, such as in the Philippines.WEB, Lynas, Mark, August 26, 2013, Anti-GMO Activists Lie About Attack on Rice Crop (and About So Many Other Things),weblink August 21, 2021, Slate (magazine), Slate Magazine, In 2016 more than 100 Nobel laureates encouraged the use of genetically modified organisms, such as golden rice, for the benefits these could bring.JOURNAL, Roberts, Richard J., The Nobel Laureates' Campaign Supporting GMOs, Journal of Innovation & Knowledge, 3, 2, 2018, 10.1016/j.jik.2017.12.006, 61–65, free,

Rice and climate change

Greenhouse gases from rice production

(File:NP Rice Emissions18 (5687953086).jpg|thumb|Scientists measure the greenhouse gas emissions of rice.)In 2022, greenhouse gas emissions from rice cultivation were estimated at 5.7 billion tonnes CO2eq, representing 1.2% of total emissions.WEB, Sectors: Rice cultivation,weblink December 7, 2023, climatetrace.org, Within the agriculture sector, rice produces almost half the greenhouse gas emissions from croplands,JOURNAL, Qian, Haoyu, Zhu, Xiangchen, Huang, Shan, Linquist, Bruce, Kuzyakov, Yakov, Wassmann, Reiner, Minamikawa, Kazunori, Martinez-Eixarch, Maite, Yan, Xiaoyuan, Zhou, Feng, Sander, Bjoern Ole, Zhang, Weijian, Shang, Ziyin, Zou, Jianwen, Zheng, Xunhua, 5, October 2023, Greenhouse gas emissions and mitigation in rice agriculture,weblink Nature Reviews Earth & Environment, 4, 10, 716–732, 10.1038/s43017-023-00482-1, 2023NRvEE...4..716Q, 263197017, 2662-138X, Rice paddies …. account for ~48% of greenhouse gas (GHG) emissions from croplands., 20.500.12327/2431, free, some 30% of agricultural methane emissions, and 11% of agricultural nitrous oxide emissions.JOURNAL, Gupta, Khushboo, Kumar, Raushan, Baruah, Kushal Kumar, Hazarika, Samarendra, Karmakar, Susmita, Bordoloi, Nirmali, Greenhouse gas emission from rice fields: a review from Indian context, Environmental Science and Pollution Research International, 28, 24, 30551–30572, June 2021, 33905059, 10.1007/s11356-021-13935-1, 2021ESPR...2830551G, 233403787, Methane is released from rice fields subject to long-term flooding, as this inhibits the soil from absorbing atmospheric oxygen, resulting in anaerobic fermentation of organic matter in the soil.JOURNAL, Neue, H. U., 1993, Methane emission from rice fields: Wetland rice fields may make a major contribution to global warming,weblink BioScience, 43, 7, 466–473, 10.2307/1311906, 1311906, February 4, 2008,weblink" title="web.archive.org/web/20080115013146weblink">weblink January 15, 2008, dead, Emissions can be limited by planting new varieties, not flooding continuously, and removing straw.JOURNAL, Qian, Haoyu, Zhu, Xiangchen, Huang, Shan, Linquist, Bruce, Kuzyakov, Yakov, Wassmann, Reiner, Minamikawa, Kazunori, Martinez-Eixarch, Maite, Yan, Xiaoyuan, Zhou, Feng, Sander, Bjoern Ole, Zhang, Weijian, Shang, Ziyin, Zou, Jianwen, Zheng, Xunhua, 5, October 2023, Greenhouse gas emissions and mitigation in rice agriculture,weblink Nature Reviews Earth & Environment, en, 4, 10, 716–732, 10.1038/s43017-023-00482-1, 2023NRvEE...4..716Q, 263197017, 2662-138X, 20.500.12327/2431, free, It is possible to cut methane emissions in rice cultivation by improved water management, combining dry seeding and one drawdown, or executing a sequence of wetting and drying. This results in emission reductions of up to 90% compared to full flooding and even increased yields.WEB, Searchinger, Tim, Adhya, Tapan K., 2014, Wetting and Drying: Reducing Greenhouse Gas Emissions and Saving Water from Rice Production,weblink WRI,

Effects of climate change on rice production

A 2010 study found that, as a result of rising temperatures and decreasing solar radiation during the later years of the 20th century, the rice yield, measured at over 200 farms in seven Asian countries, decreased by between 10% and 20%. This may be caused by increased night-time respiration.JOURNAL, Welch, Jarrod R., Vincent, Jeffrey R., Auffhammer, Maximilian, Moya, Piedad F., Dobermann, Achim, Dawe, David, Rice yields in tropical/subtropical Asia exhibit large but opposing sensitivities to minimum and maximum temperatures, Proceedings of the National Academy of Sciences, 107, 33, August 9, 2010, 0027-8424, 10.1073/pnas.1001222107, 14562–14567, 20696908, 2930450, free, WEB, Black, R., August 9, 2010,weblink Rice yields falling under global warming,weblink" title="web.archive.org/web/20180405034821weblink">weblink April 5, 2018, BBC News: Science & Environment, August 9, 2010, IRRI has predicted that Asian rice yields will fall by some 20% per 1°C rise in global mean temperature. Further, rice is unable to yield grain if the flowers experience a temperature of 35°C or more for over one hour, so the crop would be lost under these conditions.JOURNAL, Singh, S.K., 2016, Climate Change: Impact on Indian Agriculture & its Mitigation, Journal of Basic and Applied Engineering Research, 3, 10, 857–859, BOOK, Rao, Prakash, Patil, Y.,weblink Reconsidering the Impact of Climate Change on Global Water Supply, Use, and Management, IGI Global, 2017, 978-1-5225-1047-5, 330, In the Po Valley in Italy, the arborio and carnaroli risotto rice varieties have suffered poor harvests through drought in the 21st century. The {{ill|Ente Nazionale Risi|it}} is developing drought-resistant varieties; its nuovo prometeo variety has deep roots that enable it to tolerate drought, but is not suitable for risotto.NEWS, Spaggiari, Ottavia, Risotto crisis: the fight to save Italy's beloved dish from extinction,weblink The Guardian, February 29, 2024, {{Anchor|Pests}}

Pests, weeds, and diseases

Pests and weeds

File:Chinese rice grasshopper (Oxya chinensis).jpg|thumb|Chinese rice grasshopper (Oxya chinensisOxya chinensisRice yield can be reduced by weed growth, and a wide variety of pests including insects, nematodes, rodents such as rats, snails, and birds.WEB, Pests and diseases management,weblink International Rice Research Institute, January 4, 2024, Major rice insect pests include armyworms, rice bugs, black bugs, cutworms, field crickets, grasshoppers, leafhoppers, mealybugs, and planthoppers.WEB, Insects,weblink International Rice Research Institute, January 4, 2024, High rates of nitrogen fertilizer application may worsen aphid outbreaks.JOURNAL, Jahn, Gary C., Almazan, Liberty P., Pacia, Jocelyn B., 10.1603/0046-225X-34.4.938, Effect of Nitrogen Fertilizer on the Intrinsic Rate of Increase of Hysteroneura setariae (Thomas) (Homoptera: Aphididae) on Rice (Oryza sativa L.), 2005, 1941852, Environmental Entomology, 34, 4, 938, free, Weather conditions can contribute to pest outbreaks: rice gall midge outbreaks are worsened by high rainfall in the wet season, while thrips outbreaks are associated with drought.BOOK, Douangboupha, B., Khamphoukeo, K., Inthavong, S., Schiller, J.M., Jahn, G.C., 2006,weblink Chapter 17: Pests and diseases of the rice production systems of Laos,weblink" title="web.archive.org/web/20120403052249weblink">weblink April 3, 2012, 265–281, Schiller, J.M., Chanphengxay, M.B., Linquist, B., Rao, S.A., Rice in Laos, International Rice Research Institute, Los Baños, Philippines, 978-971-22-0211-7,

Diseases

File:Rice blast.jpg|thumb|upright=0.6|Healthy rice (left) and rice with rice blast ]] Rice blast, caused by the fungus Magnaporthe grisea, is the most serious disease of growing rice.JOURNAL, 3, Dean, Ralph A., Talbot, Nicholas J., Ebbole, Daniel J., Farman, Mark L., Mitchell, Thomas K., Orbach, Marc J., Thon, Michael, Kulkarni, Resham, Xu, Jin-Rong, Pan, Huaqin, The genome sequence of the rice blast fungus Magnaporthe grisea, Nature, 434, 7036, 980–986, April 2005, 15846337, 10.1038/nature03449, free, 2005Natur.434..980D, It and bacterial leaf streak (caused by Xanthomonas oryzae pv. oryzae) are perennially the two worst rice diseases worldwide; they are both among the ten most important diseases of all crop plants.JOURNAL, Liu, Wende, Liu, Jinling, Triplett, Lindsay, Leach, Jan E., Wang, Guo-Liang, Novel Insights into Rice Innate Immunity Against Bacterial and Fungal Pathogens, Annual Review of Phytopathology, 52, 1, August 4, 2014, 0066-4286, 10.1146/annurev-phyto-102313-045926, 213–241, 24906128, Other major rice diseases include sheath blight (caused by Rhizoctonia solani), false smut (Ustilaginoidea virens), and bacterial panicle blight (Burkholderia glumae). Viral diseases include rice bunchy stunt, rice dwarf, rice tungro, and rice yellow mottle.JOURNAL, Hibino, H., Biology and epidemiology of rice viruses, Annual Review of Phytopathology, 34, 1, 249–274, 1996, 15012543, 10.1146/annurev.phyto.34.1.249, Annual Reviews (publisher), Annual Reviews,

Pest management

{{further|Integrated pest management|rice-duck farming}}Crop protection scientists are developing sustainable techniques for managing rice pests.BOOK, Jahn, Gary C., Khiev. B., Pol, C., Chhorn, N., Pheng, S., Preap, V., 2001, Developing sustainable pest management for rice in Cambodia, 243–258, Suthipradit S., Kuntha C., Lorlowhakarn, S., Rakngan, J., Sustainable Agriculture: Possibility and Direction, Bangkok (Thailand), National Science and Technology Development Agency, Sustainable pest management is based on four principles: biodiversity, host plant resistance, landscape ecology, and hierarchies in a landscape—from biological to social.JOURNAL, Savary, S., Horgan, F., Willocquet, L., Heong, A review of principles for sustainable pest management in rice, 2012, Crop Protection, 32, 54, 10.1016/j.cropro.2011.10.012, 2012CrPro..32...54S, Farmers' pesticide applications are often unnecessary.WEB,weblink Bangladeshi farmers banish insecticides, SCIDEV.net, July 30, 2004, May 13, 2012, dead,weblink" title="web.archive.org/web/20080126115934weblink">weblink January 26, 2008, Pesticides may actually induce resurgence of populations of rice pests such as the brown planthopper, both by destroying beneficial insects and by enhancing the pest's reproduction.JOURNAL, Wu, Jincai, Ge, Linquan, Liu, Fang, Song, Qisheng, Stanley, David, Pesticide-Induced Planthopper Population Resurgence in Rice Cropping Systems, Annual Review of Entomology, 65, 1, January 7, 2020, 0066-4170, 10.1146/annurev-ento-011019-025215, 409–429, 31610135, 204702698, The International Rice Research Institute (IRRI) demonstrated in 1993 that an 87.5% reduction in pesticide use can lead to an overall drop in pest numbers.WEB, The pesticide paradox, Hamilton, Henry Sackville, International Rice Research Institute, January 18, 2008,weblinkweblink" title="web.archive.org/web/20120119053923weblink">weblink January 19, 2012, File:Penggembala Bebek.jpg|thumb|left|A farmer grazes his ducks in paddy fieldpaddy fieldFarmers in China, Indonesia and the Philippines have traditionally managed weeds and pests by the polycultural practice of raising ducks and sometimes fish in their rice paddies. These produce valuable additional crops, eat small pest animals, manure the rice, and in the case of ducks also control weeds.WEB, Bezemer, Marjolein, October 23, 2022, Mixed farming increases rice yield,weblink live,weblink October 11, 2019, January 2, 2024, reNature Foundation, JOURNAL, Cagauan, A. G., Branckaert, R. D., Van Hove, C., Integrating fish and azolla into rice-duck farming in Asia, Naga (ICLARM Quarterly), 23, 1, 4–10, 2000,weblink Rice plants produce their own chemical defences to protect themselves from pest attacks. Some synthetic chemicals, such as the herbicide 2,4-D, cause the plant to increase the production of certain defensive chemicals and thereby increase the plant's resistance to some types of pests.JOURNAL, Xin, Zhaojun, Yu, Zhaonan, Erb, Matthias, Turlings, Ted C. J., Wang, Baohui, Qi, Jinfeng, Liu, Shengning, Lou, Yonggen, 5, The broad-leaf herbicide 2,4-dichlorophenoxyacetic acid turns rice into a living trap for a major insect pest and a parasitic wasp, The New Phytologist, 194, 2, 498–510, April 2012, 22313362, 10.1111/j.1469-8137.2012.04057.x, Conversely, other chemicals, such as the insecticide imidacloprid, appear to induce changes in the gene expression of the rice that make the plant more susceptible to certain pests.JOURNAL, Cheng, Yao, Shi, Zhao-Peng, Jiang, Li-Ben, Ge, Lin-Quan, Wu, Jin-Cai, Jahn, Gary C., Possible connection between imidacloprid-induced changes in rice gene transcription profiles and susceptibility to the brown plant hopper Nilaparvatalugens Stål (Hemiptera: Delphacidae), Pesticide Biochemistry and Physiology, 102-531, 3, 213–219, March 2012, 22544984, 3334832, 10.1016/j.pestbp.2012.01.003, Plant breeders have created rice cultivars incorporating resistance to various insect pests. Conventional plant breeding of resistant varieties has been limited by challenges such as rearing insect pests for testing, and the great diversity and continuous evolution of pests. Resistance genes are being sought from wild species of rice, and genetic engineering techniques are being applied.JOURNAL, Makkar, Gurpreet Singh, Bhatia, Dharminder, Suri, K.S., Kaur, Simranjeet, Insect resistance in Rice (Oryza sativa L.): overview on current breeding interventions, International Journal of Tropical Insect Science, 39, 4, 2019, 1742-7592, 10.1007/s42690-019-00038-1, 259–272, 202011174, {{Anchor|Ecotypes|Ecotype|Cultivars|Cultivar}}

Ecotypes and cultivars

File:Rice diversity.jpg|thumb|Rice seed collection from IRRIIRRI The International Rice Research Institute maintains the International Rice Genebank, which holds over 100,000 rice varieties.WEB,weblink The International Rice Genebank – conserving rice, International Rice Research Institute,weblink" title="web.archive.org/web/20121023054703weblink">weblink October 23, 2012, JOURNAL, Jackson, M. T., Conservation of rice genetic resources: the role of the International Rice Genebank at IRRI, Plant Molecular Biology, 35, 1–2, 61–67, September 1997, 9291960, 10.1023/A:1005709332130, 3360337, Much of southeast Asia grows sticky or glutinous rice varieties.JOURNAL, Sattaka, Patcha, December 27, 2016, Geographical Distribution of Glutinous Rice in the Greater Mekong Sub-region,weblink Journal of Mekong Societies, en, 12, 3, 27–48, 2697-6056, High-yield cultivars of rice suitable for cultivation in Africa, called the New Rice for Africa (NERICA), have been developed to improve food security and alleviate poverty in Sub-Saharan Africa.WEB, NERICA: Rice for Life, Africa Rice Center (WARDA), 2001,weblinkweblink" title="web.archive.org/web/20031204153208weblink">weblink dead, December 4, 2003, July 7, 2008, The complete genome of rice was sequenced in 2005, making it the first crop plant to reach this status.NEWS, Gillis, J., Rice Genome Fully Mapped, August 11, 2005, The Washington Post,weblink September 10, 2017,weblink" title="web.archive.org/web/20170330212346weblink">weblink March 30, 2017, live, Since then, the genomes of hundreds of types of rice, both wild and cultivated, and including both Asian and African rice species, have been sequenced.JOURNAL, Shang, Lianguang, Li, Xiaoxia, He, Huiying, Yuan, Qiaoling, Song, Yanni, Wei, Zhaoran, Lin, Hai, Hu, Min, Zhao, Fengli, Zhang, Chao, Li, Yuhua, Gao, Hongsheng, Wang, Tianyi, Liu, Xiangpei, Zhang, Hong, 5, 2022, A super pan-genomic landscape of rice, Cell Research, en, 32, 10, 878–896, 10.1038/s41422-022-00685-z, 1748-7838, 9525306, 35821092,

Biotechnology

High-yielding varieties

The high-yielding varieties are a group of crops created during the Green Revolution to increase global food production radically. The first Green Revolution rice variety, IR8, was produced in 1966 at the International Rice Research Institute through a cross between an Indonesian variety named "Peta" and a Chinese variety named "Dee Geo Woo Gen".WEB, Hettel, Gene, IR8—a rice variety for the ages,weblink Rice Today, December 29, 2023, November 18, 2016, Green Revolution varieties were bred to have short strong stems so that the rice would not lodge or fall over. This enabled them to stay upright and productive even with heavy applications of fertilizer.

Expression of human proteins

Ventria Bioscience has genetically modified rice to express lactoferrin and lysozyme which are proteins usually found in breast milk, and human serum albumin. These proteins have antiviral, antibacterial, and antifungal effects.JOURNAL, Marris, E., Rice with human proteins to take root in Kansas, Nature, May 18, 2007, 84688423, 10.1038/news070514-17, Rice containing these added proteins can be used as a component in oral rehydration solutions to treat diarrheal diseases, thereby shortening their duration and reducing recurrence. Such supplements may also help reverse anemia.JOURNAL, Bethell, D.R., Huang, J., Recombinant human lactoferrin treatment for global health issues: iron deficiency and acute diarrhea, Biometals, 17, 3, 337–342, June 2004, 15222487, 10.1023/B:BIOM.0000027714.56331.b8, 3106602,

Flood-tolerant rice

File:Researchers checking deep water rice.jpg|thumb|International Rice Research Institute researchers checking deepwater ricedeepwater riceIn areas subject to flooding, farmers have long planted flood tolerant varieties known as deepwater rice. In South and South East Asia, flooding affects some {{convert|20|e6ha|e6acre|abbr=off}} each year.JOURNAL, Debrata, Panda, Sarkar, Ramani Kumar, 2012, Role of Non-Structural Carbohydrate and its Catabolism Associated with Sub 1 QTL in Rice Subjected to Complete Submergence, Experimental Agriculture, 48, 4, 502–512, 10.1017/S0014479712000397, 86192842, Flooding has historically led to massive losses in yields, such as in the Philippines, where in 2006, rice crops worth $65 million were lost to flooding."WEB,weblink Climate change-ready rice,weblink" title="web.archive.org/web/20121028234824weblink">weblink October 28, 2012, International Rice Research Institute, October 31, 2013, Standard rice varieties cannot withstand stagnant flooding for more than about a week, since it disallows the plant access to necessary requirements such as sunlight and gas exchange. The Swarna Sub1 cultivar can tolerate week-long submergence, consuming carbohydrates efficiently and continuing to grow. So-called "scuba rice"WEB, Gautam, Priyanka, etal, Nutrient Management for Enhancing Submergence Tolerance in Rice,weblink National Rice Research Institute, Cuttack, Odisha, India, 3, 2017, NRRI Research Bulletin No. 13, with the Sub1A transgene is robustly tolerant of submergence for as long as two weeks, offering much improved flood survival for farmers' crops. IRRI has created Sub1A varieties and distributed them to Bangladesh, India, Indonesia, Nepal, and the Philippines.JOURNAL, Emerick, Kyle, Ronald, Pamela C., Sub1 Rice: Engineering Rice for Climate Change, Cold Spring Harbor Perspectives in Biology, 11, 12, 2019, 1943-0264, 31182543, 6886445, 10.1101/cshperspect.a034637, a034637,

Drought-tolerant rice

Drought represents a significant environmental stress for rice production, with {{convert|19-23|e6ha|e6acre|abbr=off}} of rainfed rice production in South and South East Asia often at risk.WEB,weblink Drought, submergence and salinity management,weblink" title="web.archive.org/web/20131101131821weblink">weblink November 1, 2013, International Rice Research Institute (IRRI), September 29, 2013, "WEB,weblink Climate change-ready rice,weblink" title="web.archive.org/web/20140314033307weblink">weblink March 14, 2014, International Rice Research Institute (IRRI), September 29, 2013, Under drought conditions, without sufficient water to afford them the ability to obtain the required levels of nutrients from the soil, conventional commercial rice varieties can be severely affected—as happened for example in India early in the 21st century.WEB,weblink Newly-discovered rice gene goes to the root of drought resistance,weblink" title="web.archive.org/web/20131103182251weblink">weblink November 3, 2013, Palmer, Neil, 2013, International Center for Tropical Agriculture, September 29, 2013, The International Rice Research Institute conducts research into developing drought-tolerant rice varieties, including the varieties Sahbhagi Dhan, Sahod Ulan, and Sookha dhan, currently being employed by farmers in India, the Philippines, and Nepal respectively. In addition, in 2013 the Japanese National Institute for Agrobiological Sciences led a team which successfully inserted the DEEPER ROOTING 1 (DRO1) gene, from the Philippine upland rice variety Kinandang Patong, into the popular commercial rice variety IR64, giving rise to a far deeper root system in the resulting plants. This facilitates an improved ability for the rice plant to derive its required nutrients in times of drought via accessing deeper layers of soil, a feature demonstrated by trials which saw the IR64 + DRO1 rice yields drop by 10% under moderate drought conditions, compared to 60% for the unmodified IR64 variety.WEB,weblink Roots breakthrough for drought resistant rice,weblink" title="web.archive.org/web/20131102113839weblink">weblink November 2, 2013, Phys.org, 2013, September 30, 2013,

Salt-tolerant rice

{{further|Crop tolerance to seawater}}Soil salinity poses a major threat to rice crop productivity, particularly along low-lying coastal areas during the dry season.WEB, International Rice Research Institute, Rice Breeding Course, Breeding for salt tolerance in rice, on line,weblinkweblink" title="web.archive.org/web/20170505220950weblink">weblink May 5, 2017, For example, roughly {{convert|1|e6ha|e6acre|abbr=off}} of the coastal areas of Bangladesh are affected by saline soils."WEB,weblink Less salt, please,weblink" title="web.archive.org/web/20131101133710weblink">weblink 1 November 2013, Fredenburg, P., 2007, 30 September 2013, International Rice Research Institute, These high concentrations of salt can severely affect rice plants' physiology, especially during early stages of growth, and as such farmers are often forced to abandon these areas."WEB,weblink Wild parent spawns super salt tolerant rice, Barona-Edna, Liz, April 15, 2013, January 3, 2024, Rice Today, Progress has been made in developing rice varieties capable of tolerating such conditions; the hybrid created from the cross between the commercial rice variety IR56 and the wild rice species Oryza coarctata is one example."WEB,weblink Breakthrough in salt-resistant rice research—single baby rice plant may hold the future to extending rice farming,weblink November 2, 2013, Integrated Breeding Platform (IBP), 2013, October 6, 2013, O. coarctata can grow in soils with double the limit of salinity of normal varieties, but does not produce edible rice. Developed by the International Rice Research Institute, the hybrid variety utilises specialised leaf glands that remove salt into the atmosphere. It was produced from one successful embryo out of 34,000 crosses between the two species; this was then backcrossed to IR56 with the aim of preserving the genes responsible for salt tolerance that were inherited from O. coarctata.

Cold tolerance

Rice is sensitive to temperatures below 12C. Sowing takes place once the daily average temperature is reliably above this limit. Average temperatures below that reduce growth; if sustained for over four days, germination and seedling growth are harmed and seedlings may die. In larger plants subjected to cold, rice blast is encouraged, seriously reducing yield. As of 2022, researchers continue to study the mechanisms of chilling tolerance in rice and its genetic basis.JOURNAL, Li, Junhua, Zhang, Zeyong, Chong, Kang, Xu, Yunyuan, Chilling tolerance in rice: Past and present, Journal of Plant Physiology, 268, 2022, 10.1016/j.jplph.2021.153576, 153576,

Environment-friendly rice

Producing rice in paddies is harmful for the environment due to the release of methane by methanogenic bacteria. These bacteria live in the anaerobic waterlogged soil, consuming nutrients released by rice roots. Putting the barley gene SUSIBA2 into rice creates a shift in biomass production from root to shoot, decreasing the methanogen population, and resulting in a reduction of methane emissions of up to 97%. Further, the modification increases the amount of rice grains.JOURNAL, Su, J., Hu, C., Yan, X., Jin, Y., Chen, Z., Guan, Q., Wang, Y., Zhong, D., Jansson, C., Wang, F., Schnürer, A., Sun, C., 5, Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice, Nature, 523, 7562, 602–606, July 2015, 26200336, 10.1038/nature14673, 4454200, 2015Natur.523..602S, WEB, Gerry, C., Feeding the World One Genetically Modified Tomato at a Time: A Scientific Perspective,weblink Harvard University, September 11, 2015, August 9, 2015,weblink" title="web.archive.org/web/20150910164510weblink">weblink September 10, 2015, live,

Model organism

Rice is used as a model organism for investigating the mechanisms of meiosis and DNA repair in higher plants.JOURNAL, Luo, Qiong, Li, Yafei, Shen, Yi, Cheng, Zhukuan, Ten years of gene discovery for meiotic event control in rice, Journal of Genetics and Genomics, 41, 3, 125–137, March 2014, 24656233, 10.1016/j.jgg.2014.02.002, free, For example, study using rice has shown that the gene OsRAD51C is necessary for the accurate repair of DNA double-strand breaks during meiosis.JOURNAL, Tang, Ding, Miao, Chunbo, Li, Yafei, Wang, Hongjun, Liu, Xiaofei, Yu, Hengxiu, Cheng, Zhukuan, OsRAD51C is essential for double-strand break repair in rice meiosis, Frontiers in Plant Science, 5, 167, 2014, 24847337, 4019848, 10.3389/fpls.2014.00167, free, {{Anchor|Culture}}

In human culture

File:COLLECTIE TROPENMUSEUM Beeld van Dewi Sri de rijstgodin TMnr 60016918.jpg|thumb|upright|Ancient statue of the rice goddess 9th century}}) Rice plays an important role in certain religions and popular beliefs. In Hindu wedding ceremonies, rice, denoting fertility, prosperity, and purity, is thrown into the sacred fire, a custom modified in Western weddings, where people throw rice.JOURNAL, Ahuja, Subhash C., Ahuja, Uma, Rice in religion and tradition, 2nd International Rice Congress, October 9–13, 2006, 2006,weblink New Delhi, 45–52, In Malay weddings, rice features in multiple special wedding foods such as sweet glutinous rice.JOURNAL, Muhammad, Rosmaliza, Zahari, Mohd Salehuddin Mohd, Ramly, Alina Shuhaida Muhammad, Ahmad, Roslina, The Roles and Symbolism of Foods in Malay Wedding Ceremony, Procedia - Social and Behavioral Sciences, 101, 2013, 1877-0428, 10.1016/j.sbspro.2013.07.200, 268–276, free, In Japan and the Philippines, rice wine is used for weddings and other celebrations.JOURNAL, Ahuja, Uma, Thakrar, Rashmi, Ahuja, S. C., 2001, Alcoholic rice beverages, Asian Agri-History, 5, 4, 309–319,weblink Dewi Sri is a goddess of the Indo-Malaysian archipelago, who in myth is transformed into rice or other crops.JOURNAL, Wessing, Robert, Sri and Sedana and Sita and Rama: Myths of Fertility and Generation, Asian Folklore Studies, 49, 2, 1990, 235–257, 10.2307/1178035, 1178035, The start of the rice planting season is marked in Asian countries including Nepal and Cambodia with a Royal Ploughing Ceremony.NEWS, Cambodia marks beginning of farming season with royal ploughing ceremony, Xinhua, March 21, 2017,weblinkweblink" title="web.archive.org/web/20180503130501weblink">weblink dead, May 3, 2018, en, December 6, 2021, WEB, Ceremony Predicts Good Year, Khmer Times, May 23, 2016,weblink December 6, 2021, WEB, Sen, S., Ancient royal paddy planting ceremony marked, The Himalayan Times, July 2, 2019,weblink December 6, 2021,

See also

• Artificial rice

• Direct seeded rice

• List of rice dishes

• Rice Belt

{{-}}

References

{{reflist}}

Further reading

• JOURNAL, Liu, Wende, Liu, Jinling, Triplett, Lindsay, Leach, Jan E., Wang, Guo-Liang, Novel insights into rice innate immunity against bacterial and fungal pathogens, Annual Review of Phytopathology, 52, 1, 213–241, August 4, 2014, 24906128, 10.1146/annurev-phyto-102313-045926, Annual Reviews (publisher), Annual Reviews, 9244874, none,
• JOURNAL, Deb, D., Restoring Rice Biodiversity, Scientific American, 321, 4, October 2019, 54–61, India originally possessed some 110,000 landraces of rice with diverse and valuable properties. These include enrichment in vital nutrients and the ability to withstand flood, drought, salinity or pest infestations. The Green Revolution covered fields with a few high-yielding varieties, so that roughly 90 percent of the landraces vanished from farmers' collections. High-yielding varieties require expensive inputs. They perform abysmally on marginal farms or in adverse environmental conditions, forcing poor farmers into debt., none,
• BOOK, Singh, B. N., 2018, Global Rice Cultivation & Cultivars,weblink New Delhi, Studium Press, 978-1-62699-107-1, March 14, 2018,weblink" title="web.archive.org/web/20180314175208weblink">weblink March 14, 2018, dead, none,

{{Varieties of rice}}{{Rice production}}{{Cereals}}{{Agriculture country lists}}{{Rice dishes}}{{Authority control}}

- content above as imported from Wikipedia
- "Rice" does not exist on GetWiki (yet)
- time: 3:27pm EDT - Wed, May 15 2024