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The '''System of Rice Intensification (SRI)''' was developed as a methodology aimed at increasing the yield of rice produced in irrigated farming without relying on purchased inputs. Its main elements were assembled in 1983 by the French Jesuit Father [[Henri de |
The '''System of Rice Intensification (SRI)''' was developed as a methodology aimed at increasing the yield of rice produced in irrigated farming without relying on purchased inputs. Its main elements were assembled in 1983 by the French Jesuit Father [[Henri de Laulanie]] in Madagascar after 20 years of observation and experimentation.[1] However, systematic evaluation and then dissemination of the system did not occur until some 10-20 years later. The productivity and merits of SRI have been debated between supporters and critics of the system since 2004, but the controversy has waned in recent years. |
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==History and Main Ideas of SRI== |
==History and Main Ideas of SRI== |
Revision as of 09:37, 18 February 2013
The System of Rice Intensification (SRI) was developed as a methodology aimed at increasing the yield of rice produced in irrigated farming without relying on purchased inputs. Its main elements were assembled in 1983 by the French Jesuit Father Henri de Laulanie in Madagascar after 20 years of observation and experimentation.[1] However, systematic evaluation and then dissemination of the system did not occur until some 10-20 years later. The productivity and merits of SRI have been debated between supporters and critics of the system since 2004, but the controversy has waned in recent years.
History and Main Ideas of SRI
Assembly of the practices that culminated in SRI began in the 1960s based on Fr. de Laulanie's observations of 'deviant' farmer practices and his own experimentation. Principles included applying a minimum quantity of water, instead of continuous flooding, and the individual transplanting of very young seedlings in a square pattern to give plants more room for root and tiller growth.[1]
SRI concepts and practices have continued to evolve as they are being adapted to rain-fed (unirrigated) conditions and with transplanting being superseded sometimes by direct-seeding. Regarding the management of rice plants, the basic practices of SRI according to SRI-Rice at Cornell University are:[2]
- Rice plant seedlings should be transplanted very young (usually just 8-12 days old) with just two small leaves
- Seedlings should be transplanted carefully and quickly to inflict minimum trauma on the roots
- Seedlings should be transplanted singly, with only one per hill instead of 3-4 together to minimize root competition
- Seedlings should be widely spaced to encourage greater root and canopy growth
- Seedlings should be transplanted in a square grid pattern (25x25 cm, or wider in good quality soil)
Since SRI is not a recipe of precise things to do, but rather a menu of principles and practices for bringing out rice plants' potential, SRI-Rice at Cornell University recommends:[3]
- Soil is kept moist but well-drained and aerobic, with good structure and enough organic matter to support increased biological activity. The quality and health of the soil is the key to best production.
- Only a minimum amount of water is applied during the vegetative growth period, and thereafter only a thin layer of water is maintained on the field during flowering and grain-filling. Alternatively, to save labor time, some farmers flood and drain (dry) their SRI fields in 3-5 day cycles with good results. Best water management practices depend on soil type, labor availability and other factors, so farmers should experiment on how best to apply the principle of having moist but well-drained soil while their rice plants are growing.
- Soil nutrient supplies should be augmented, preferably with compost, made from any available biomass. Better quality compost such as with manure can give additional yield advantages. Chemical fertilizer can be used and gives better results than with no nutrient amendments, but it does not enhance soil structure and microbial communities in the rhizosphere as applying organic matter accomplishes. At least initially, nutrient amendments may not be necessary to achieve higher yields with the other SRI practices, but it is desirable to build up soil fertility over time. Root exudation, greater with SRI, enhances soil fertility.
- Since weeds become a problem in fields that are not kept flooded, weeding is necessary several times, starting 10-12 days after transplanting, and if possible, every 10-12 days until the canopy closes. Using a rotary hoe -- a simple, inexpensive, mechanical push-weeder -- has the advantage of aerating the soil at the same time that weeds are eliminated. (They are left in the soil to decompose so their nutrients are not lost.) Additional weedings beyond two can increase yield more than enough under most conditions to more than justify the added labor costs.
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. Today, the spread of SRI is supported by SRI-Rice at Cornell University, an organization devoted to advancing and promoting SRI knowledge globally.
Evaluating SRI
Proponents and critics of SRI have debated the claimed benefits, and many questions about it remain unresolved.[4] The International Rice Research Institute has published information on the challenges of evaluating SRI stating that, "the flexibility in SRI’s definition of practices renders SRI a challenge for evaluation and assessment of adoption." [1] Wageningen University has also published an article discussing the challenges of evaluating SRI in which one concluding sentence read: "Although the technical aspects of SRI have been contested, it clearly exists as a real social phenomenon".[6] The question at hand seems to be: is SRI better at delivering increased yield and other benefits to rice farmers, such as healthier soils, when compared with established recommended best management practices for rice production?
Lessons from SRI studies
Results from the field studies of Directorate of Rice Research (DRR) conducted in four seasons and also AICRIP trials as present in the Rice Knowledge Management Portal, indicate good scope for saving irrigation besides improving rice growth and production. However, water saving could be attributed to reduction in water losses through percolation/seepage/ runoff/evaporation that are common with flooded rice culture. Increased productivity is associated with improved plant growth, yield attributes and higher grain output has been apparent[7].
Cases of success
Proponents of SRI claim its use increases yield, saves water, reduces production costs, and increases income, and that benefits have been achieved in almost 50 countries.[8] Uphoff published an article in the International Journal of Agricultural Sustainability that states that SRI "can raise irrigated rice yields to about double the present world average without relying on external inputs, also offering environmental and equity benefits."[9] A special issue on SRI in the scientific journal Paddy and Water Environment collected recent findings in support of SRI.[10] SRI principles have been applied in many regions to various other important crops for increasing productivity and establishing food security besides rice. Through the work of various NGO partners working in the SDTT-supported SRI [1] programme, India today has emerged as the largest adopted System of Crop Intensification (SCI) efforts in the world. As spill-over effect, innovations on wheat, kidney beans, millets, mustard, sugarcane, grams, vegetables even have been extensive with several thousands of farmers in states like Bihar and Uttarakhand extending SRI ideas and methods to other food crops. This phenomenon of extending beyond rice is significant and merits closer attention by policy makers.
Criticism
Critics of SRI suggest that claims of yield increase in SRI are due to unscientific evaluations, and further that the definition of SRI is a vague moving target, and therefore difficult to evaluate. They object that there is a lack of details on the methodology used in trials and a lack of publications in the peer-reviewed literature.[11][12] Some critics have suggested that SRI success is unique to soil conditions in Madagascar.[13] The scientific literature on SRI has burgeoned, with over 250 articles now, which can be easily accessed [14].
SRI picture gallery
Below is a picture gallery of SRI farming in Chattisgarh, India:
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Planted field
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Rice field
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Nursery
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Fields left almost dry
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SRI field
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Farmer
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Crop with weeds
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Weeding
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Weeding
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Weeding
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Weeding
References
- ^ Evaluating SRI, IRRI website.
Others
- 1. ^ a b Intensive Rice Farming in Madagascar by H. De Laulanié, in Tropicultura, Vol. 29, No. 3, 2011, Pages 183-187
- 2. ^ Core SRI principles, SRI-Rice
- 3. ^ Core SRI principles, SRI-Rice
- 4. ^ Science, practice and the System of Rice Intensification in Indian agriculture in Food Policy, Volume 36, No. 6, 2011, Pages 749–755
- 5. ^ Evaluating SRI, International Rice Research Institute
- 6. ^ The System of Rice Intensification: Time for an empirical turn by D.Glover in NJAS - Wageningen Journal of Life Sciences Volume 57, Nos. 3–4, 2011, Pages 217–224
- 7. ^ http://www.rkmp.co.in/sites/default/files/ris/research-themes/SRI_Present%20Status%20and%20Future%20Prospects.pdf
- 8. ^ More rice for people, more water for planet: System of Rice Intensification (SRI) by Africare, Oxfam and WWF.
- 9. ^ Higher yields with fewer external inputs? The System of Rice Intensification and potential contributions to agricultural sustainability, in the International Journal of Agricultural Sustainability, Volume 1, Issue 11, 2003
- 10. ^ Paddy and Water Environment, Vol. 9 No. 1, 2011, Springer Verlag
- 11. ^ Does the system of rice intensification outperform conventional best management?: A synopsis of the empirical record by A.J. McDonald, P.R. Hobbs, S.J. Riha in Field Crops Research, Volume 96, No. 1, 2006, Pages 31–36
- 12. ^ Stubborn facts: Still no evidence that the System of Rice Intensification out-yields best management practices (BMPs) beyond Madagascar by A. J. McDonald, P. R. Hobbs, S. J. Riha in Field Crops Research, Volume 108, No. 2, 2008, Pages 188-191; response to critique of 2006 FCR article: N. Uphoff, A. Kassam, W. Stoop, A critical assessment of a desk study comparing crop production systems: The example of the 'system of rice intensification' vs. 'best management practices' in Field Crops Research, Vol. 108, No. 1, 2008, Pages 109-114.ancd
- 13. ^ Christopher Surridge. Rice cultivation: Feast or famine? Nature 428, 360–361 (25 March 2004). doi:10.1038/428360a
- 14. http://sri.ciifad.cornell.edu/research/JournalArticles.html
External links
- SRI-Rice (SRI International Network and Resources Center) at Cornell University
- SDTT-SRI: Website of SRI Programme supported by Sir Dorabji Tata Trust (SDTT) and Allied Trusts in India
- SRI-India Google Group: Online Network for promoting discussions and debates on SRI
- SRI-Rice on Facebook at Cornell University
- Rice Knowledge Bank: best management practices for rice production
- Krishi Usha low-cost weeder developed by Krishi Gram Vikas Kendra and Usha Martin Limited, Jharkhand
- Article on SRI from Nature
- News article on SRI from the BBC
- SRI: Achieving More with Less - A new way of rice cultivation from the World Bank Institute