The System of Rice Intensification (SRI) is a method of increasing the yield of rice produced in farming. It was invented in 1983 by the French Jesuit Father Henri de Laulanie in Madagascar. However full testing of the system did not occur until some years later. The productivity of SRI is under debate between supporters and critics of the system. For other uses, see Rice (disambiguation). ... Farming, ploughing rice paddy, in Indonesia Agriculture is the process of producing food, feed, fiber and other desired products by cultivation of certain plants and the raising of domesticated animals (livestock). ... For the Jimi Hendrix song, see 1983. ... The Society of Jesus (Latin: Societas Iesu), commonly known as the Jesuits, is a Roman Catholic religious order. ... This article is about religious workers. ...

History and main ideas of SRI

Assembly of the practices that culminated in SRI began in the 1960s based on Fr. de Laulanie's observation of 'positive-deviant' farmer practices, starting with planting single seedlings instead of multiple seedlings in a clump, and not keeping irrigated paddy fields flooded during the rice plants' vegetative growth stage. Planting with wider spacing in a square pattern, rather than randomly or in rows, followed, as did controlling weed growth by use of a soil-aerating push-weeder (rotating hoe).

In 1983, the beneficial effect of transplanting very young seedlings, less than 15 days old, was discovered serendipitously. Subsequently when fertilizer prices were raised, compost made from any decomposed biomass turned out to give even better results than chemical fertilizer. SRI concepts and practices continue to evolve as they are being adapted to rainfed (unirrigated) conditions and with transplanting being superseded by direct-seeding sometimes.

The synthesis of SRI has proceeded empirically, but the central principles for getting best results are:

• rice field soils should be kept moist rather than continuously saturated, minimizing anaerobic conditions, as this improves root growth and supports the growth and diversity of aerobic soil organisms;
• rice plants should be spaced optimally widely to permit more growth of roots and canopy and to keep all leaves photosynthetically active; and
• rice seedlings should be transplanted when young, less than 15 days old with just two leaves, quickly, shallow and carefully, to avoid trauma to roots and to minimize transplant shock.

These changes from conventional practice when managing plants, soil, water and nutrients induce more productive phenotypes from any rice genotype, although some varieties respond better than others to SRI methods. Increased yield is achieved with 80-90% reductions in seed requirements (lower plant population) and 25-50% less irrigation water. Chemical fertilizer and agrochemical crop protection can be used, but best results can be attained without use of purchased inputs.

Spread of SRI

The spread of SRI from Madagascar to around the globe has been credited to Norman Uphoff, director of the International Institute for Food, Agriculture and Development at Cornell University, Ithaca, New York from 1990 to 2005. In 1993, Uphoff met officials from Association Tefy Saina, the non-governmental organisation set up in Madagascar in 1990 by de Laulanie to promote SRI. After seeing the success of SRI for three years when Malagasy farmers previously averaging 2 tons/hectare averaged 8 tons/hectare with SRI, Uphoff became persuaded of the merits of the system, and in 1997 started to promote SRI in Asia. As of 2007, the beneficial effects of SRI methods had been documented in 28 countries, most recently in Bhutan, Iraq, Iran and Zambia. Governments in the largest rice-producing countries (China, India and Indonesia) are now supporting SRI extension. In India, SRI concepts and practices have been extrapolated successfully to other crops such as sugar cane, finger millet and wheat. Cornell redirects here. ... The City of Ithaca (named for the Greek island of Ithaca) sits on the southern shore of Cayuga Lake, in Central New York State. ... This article is about the state. ... A non-governmental organization (NGO) is an organization which is not a part of a government. ... This article is about the year. ... For the band, see 1997 (band). ... For other uses, see Asia (disambiguation). ... Species Ref: ITIS 42058 as of 2004-05-05 Sugarcane is one of six species of a tall tropical southeast Asian grass (Family Poaceae) having stout fibrous jointed stalks whose sap at one time was the primary source of sugar. ... Binomial name L. Finger millet (Eleusine coracana, Amharic ዳጉሳ Dagusa or ቶኩሶ tōkÅ«sō), also known as African millet or Ragi), is an annual plant widely grown as a cereal in the arid areas of Africa and Asia. ... Species T. aestivum T. boeoticum T. dicoccoides T. dicoccon T. durum T. monococcum T. spelta T. sphaerococcum T. timopheevii References:   ITIS 42236 2002-09-22 Wheat Wheat For the indie rock group, see Wheat (band). ...

Criticism

There are criticisms of SRI. While supporters of SRI report many benefits in addition to yield increase -- resistance to pests and diseases, resistance to abiotic stresses like drought and storm damage, more output of polished rice (in kg) when SRI paddy (unmilled rice) is processed (bushels), less chemical pollution of soil and water resources -- critics have focused on yield suggesting that claims of increase are due to "poor record keeping and unscientific thinking" [1]. Some critics have suggested that SRI success is unique to soil conditions in Madagascar, a point that is disputed by supporters. The Coat of Arms of Prince Edward Island uses two foxes as supporters. ... A critic (derived from the ancient Greek word krites meaning a judge) is a person who offers a value judgement or an interpretation. ...

Critics have objected that there is a lack of details on the methodology used in trials and a lack of publications in the peer-reviewed literature. This latter deficiency is now being remedied by such publications, but systematic trials that will satisfy scientific critics remain to be done. A global field trial is planned for 2009-2011, to be conducted by researchers from Cornell University, Wageningen University, and the International Rice Research Institute ^[1] Cornell redirects here. ... Wageningen University Established 1918 Wageningen University provides education and generates knowledge in the field of life sciences and natural resources. ...

Below is a picture gallery of SRI farming in Chattisgarh, India: Chhattisgarh (छत्तीसगढ़), a state in central India, formed when the sixteen southeastern districts of Madhya Pradesh gained statehood on November 1, 2000. ...

Planted field	Rice field	Nursery	Fields left almost dry
SRI field	Farmer Download high resolution version (640x640, 299 KB)Farmer spreading grasshopper bait in his alfalfa field. ...	Crop with weeds	Weeding
Weeding	Weeding	Weeding

External links

• SRI at Cornell University
• Article on SRI from Nature
• News article on SRI from the BBC