Ce diaporama a bien été signalé.
Le téléchargement de votre SlideShare est en cours. ×

0426 The System of Rice Intensification (SRI): Practices - Part II

Chargement dans…3

Consultez-les par la suite

1 sur 75 Publicité

Plus De Contenu Connexe

Diaporamas pour vous (20)

Similaire à 0426 The System of Rice Intensification (SRI): Practices - Part II (20)


Plus par SRI-Rice, Dept. of Global Development, CALS, Cornell University (20)

Plus récents (20)


0426 The System of Rice Intensification (SRI): Practices - Part II

  1. 1. The System of Rice Intensification (SRI): Practices Cornell International Institute for Food, Agriculture and Development (CIIFAD) and Association Tefy Saina, Madagascar
  2. 2. I. SRI Around the World: Africa, Latin America, Asia
  3. 3. An SRI field at Ambatovy, Madagascar, 2003
  4. 4. Cuba -- CPA Camilo Cienfuegos cooperative -- 14 t/ha
  5. 5. An SRI field in Sri Lanka, 2002 – 13 t/ha yield
  6. 6. SRI field in Yunnan, China, hybrid variety, 2004 – 18 t/ha
  8. 8. SRI is a set of principles and methods that help farmers get more productive rice plants from ANY VARIETY of rice SRI methods accomplish this improvement by making changes in the management of plants, soil, water, and nutrients to (a) induce greater ROOT GROWTH, and (b) nurture more abundant and diverse populations of SOIL ORGANISMS
  9. 9. SRI Practices Should Always be Varied to Suit Conditions The basic practices -- starting points -- are: • Transplant young seedlings ( < 15 days ) – although direct-seeding is becoming an option • Wide spacing – single plants, in square pattern • Soil aeration – thru water management and weeding, so aerobic conditions prevail in soil • Organic matter added to enhance the soil – fertilizer is not needed but it does raise SRI yield Weed control with ‘rotating hoe’ is recommended Farmer innovation is an important part of SRI
  10. 10. LESS CAN PRODUCE MORE by utilizing biological potentials & processes • Smaller, younger seedlings become larger, more productive mature plants • Fewer plants per hill and per m2 will give higher yield if used with other SRI practices • Half as much water produces more rice because aerobic soil conditions are better • Fewer or even no purchased inputs can make greater output possible, because soil organisms increase and are more active • Living soil is the key to SRI performance
  12. 12. Seed Preparation • Seed selection • Seed amounts • Nursery size as ratio to field • Seed preparation (soaking, warming) • Etc.
  13. 13. If Transplanting -- Start with Young Seedlings • SRI can be practiced with direct seeding • Many farmers are experimenting with this, and have good results -- saving labor • But many farmers prefer transplanting because it assures good establishment • The critical thing is to PROTECT AND TAKE GOOD CARE OF THE ROOTS • These are the key to SRI success
  14. 14. SRI Nurseries are Like a Garden • No continuous flooding of the seedlings • Soil should be light and easy to work with – so seedlings can be separated when transplanting • Mixture of organic matter with the soil Conventional nursery in Tamil Nadu, India
  15. 15. SRI nursery in Tamil Nadu, India
  16. 16. Small nursery in Sri Lanka Note that this is enough for much larger field Note also elevation of soil to keep roots from being suffocated by water Note rake-marker on left, used to mark square pattern on field
  17. 17. Transplanting is Most Important Operation for SRI • Young seedlings, 8-12 days old (< 15 d), should be removed carefully from the nursery, keeping the seed sack attached to the roots • Transplanting should be done within 15- 30 minutes after removal from nursery, keeping mud attached to root so that it does not dry out
  18. 18. 10-day-old seedlings being taken from nursery, very carefully
  19. 19. Pulling out of seedlings in Tamil Nadu Conventional SRI
  20. 20. Transport of seedlings Conventional SRI
  21. 21. Planting in a Square Pattern with Wide Spacing is Important • Square spacing will permit efficient weeding with rotary hoe • Recommend to start with 25x25 cm spacing; but 30x30 or 35x35 better? • If soil is very good, or as it improves with SRI practice, spacing can be greater, eventually to 40x40 or even 50x50 cm
  22. 22. Different Methods for Spacing • SRI was developed using strings across the field tied to sticks; this gives good precision but takes time • Most popular method now is use of a simple wooden rake with desired spacing, pulled in two directions • Most recent innovation is a roller- marker that is cheap and saves time
  23. 23. Conventional planting
  24. 24. SRI planting in Tamil Nadu
  25. 25. Field marking with rake
  26. 26. Separating seedlings for transplanting Yellow color is from sunlight
  27. 27. Planting seedlings shallow,only 1-2 cm deep, keeping seedling roots as horizontal as possible
  28. 28. Roller-marker devised by Lakshmana Reddy, East Godavari, AP, India, to mark a square pattern on field and save time in transplanting operations; his yield in 2003-04 season was 16.2 t/ha paddy rice (dry weight)
  29. 29. Transplanted fields in Tamil Nadu, India Conventional SRI
  30. 30. Careful Transplanting Is Key • Plants should be set into muddy soil no deeper than 1-2 cm • Seedlings should not be pushed down into the soil – This will turn the root tip upward and slow the plant’s resumption of growth – The seedling shape should be more like an L than like a J • Direct seeding is being experimented with by some farmers to save labor
  31. 31. Seeder developed by Luis Romero, Cuba, for planting pregerminated seed, sowing 40x40 cm (too wide)
  32. 32. Variations in Plant Establishment • Broadcast germinated seed or young seedlings – seeding rate of 25 kg/ha – developed by A. Subasinghe, Sri Lanka • After about 10 days, use rotating-hoe weeder to ‘weed’ the field as normal recommended for SRI • This THINS the crop, leaving only a few plants (1-2) at each intersection of rows • This method saves labor for making a nursery and for transplanting seedlings
  33. 33. Variations in Plant Establishment • In China, a ‘triangular’ method for trans- planting was developed by Liu Zhibin, farm manager in Meishan, Sichuan • This increases plant population by having 3 plants per hill with – wider spacing between hills and – fewer hills • The best spacing for particular soil and climate conditions and particular variety should be determined by experimentation • Spacing between plants is 7-10 cm
  34. 34. Square planting with single seedling 40cm Original 40 cm SRI
  35. 35. Oblong planting with triangle pattern 45cm 7cm Improved 40 cm SRI
  36. 36. Comparison between Triangle SRI and Standard SRI (SAAS, 2002) Comparison with CK Transplanting Yield Pattern (T/ha) + T/ha +% Traditional (CK) 8.65 -- -- Standard SRI 10.42 1.77 20.4 Oblong + triangle SRI 13.39 4.74 54.8
  37. 37. Innovation Is Part of SRI • Kadiramangalam method developed by Gopal Swaminathan, Tamil Nadu, India: – where intense summer heat is too much for tiny young seedlings, he transplants them in hills of 3 at 15 days at 30x30 cm spacing, and re-transplants at 30 days at 30x30 cm – this method takes more labor, but it gives 100% survival rate and assured yield of 8 t/ha • Farmers are encouraged to experiment with variations in timing, spacing, etc. to find best practices for their conditions
  38. 38. Innovation Is Part of SRI • Gopal Swaminathan, Tamil Nadu, India, has also developed a 4-row weeder that works with his soils and saves time • Ariyaratna Subasinghe, Sri Lanka, has built a motorized weeder that greatly reduces his labor time for weeding, so he can handle 2 ha SRI rice field by himself • Farmers are encouraged and expected to make further improvements in SRI methods as they gain experience with it
  39. 39. 4-row weeder designed by Gopal Swaminathan, Tamil Nadu, India
  40. 40. Motorized weeder developed by S. Ariyaratna, Sri Lanka
  41. 41. Weeding Is Important for Yield • This activity does more than remove weeds • Mechanical weeding with rotating hoe or cono-weeder – Returns weeds (organic matter) to the soil – Aerates the soil, supporting soil organisms • We have some evidence that additional weedings will add to yield, without fertilizer • Farmers can experiment for themselves weeding different parts of field 2x, 3x or 4x
  42. 42. Effects of Weeding on Yield Results for 76 farmers around Ambatovaky, Madagascar, 1997-98 No. of No. of Average Ave. weedings farmers yield (t/ha) increase None* 2 5.9 -- One/two 35 7.5 1.6 Three 24 9.1 1.6 Four 15 11.7 2.6 *Hand-weeding only; labor cost for weeding was about $25/ha
  43. 43. Conventional weeding
  44. 44. Rotary weeder  Handle
  45. 45. Using rotary weeder
  46. 46. Cono-weeder
  47. 47. Using cono weeder
  48. 48. Good Water Management Is Required for Best Results • During weeding, fields are flooded -- but otherwise, fields are not kept flooded • The ideal is to provide the plant with a ‘minimum of water,’ i.e., enough water to meet plants’ needs, but not so much that: – Roots’ access to oxygen is interrupted, since they air to keep from degenerating, or – Soil organisms which need oxygen are lost and only anaerobic organisms survive
  49. 49. Water Management Methods Can Vary • Original recommendation was to add small amounts of water on daily basis, preferably in afternoon or evening, enough to wet the soil, and to drain off any remaining excess the next morning • This would be done during the period of vegetative growth, with several periods of no watering for 3-6 days, to dry soil • After panicle initiation, only 1-2 cm of water is kept on the field until 10 days before harvest -- when field is drained
  50. 50. Water Management Methods Can Vary • This may be more water than needed • Many farmers practice alternate wetting and drying (AWD), flooding field for 3-6 days, then draining it to be dry 3-6 days • This reduces labor requirements; yield may be lower, but labor cost is less • Best amounts and timing of water will depend on soil and other factors • Farmers are encouraged to experiment to determine best water practices for field
  51. 51. Conventional irrigation
  52. 52. Water-saving irrigation
  53. 53. Case Study from China: Evaluation of SRI in Xinsheng Village, Dongxi Township, Jianyang County, Sichuan Province, August 2004, done for China Agricultural University (Li et al., 2004) • 2003 – 7 farmers used SRI • 2004 – 398 farmers used SRI (65%) • 2003 – SRI plot size average 0.07 mu • 2004 – SRI plot size average 0.99 mu • 86.6% of SRI farmers (65/75) said they would expand their SRI area next year or keep their whole rice area under SRI • Why the rapid acceptance of SRI?
  54. 54. 2003 WAS A DROUGHT YEAR RICE YIELD (t/ha) 2002 2003 2004 Standard 6.02 4.47 5.64 Methods SRI Methods -- 6.60 7.61 (SRI Increase) (46.6%) (34.8%) Water saving/ha was calculated at 43.2% • However, farmers in both questionnaire survey and discussion groups said that labor-saving was SRI’s greatest benefit
  55. 55. IV. Advantages of SRI beyond Yield Increases
  56. 56. • Cost reduction and increased profitability – can reduce water, seed, labor and other inputs • Lower capital requirements – more accessible for poorer households, help with food security • Resistence to pests and diseases – farmers can reduce or end their use of agrochemical sprays • Resistance to climatic effects – greater tolerance to drought, cold, storm and salinity, no lodging • Environmental benefits – less chemical use, lower water demand, fewer greenhouse gases? • Lower risk – less chance of net losses from rice production • Higher grain quality – higher milling out-turn, better eating qualities, more nutritious rice? • Biodiversity conservation – traditional varieties
  57. 57. Other Benefits from SRI Methods
  58. 58. Two rice fields in Sri Lanka -- same variety, same irrigation system, and same drought : conventional methods (left), SRI (right)
  59. 59. MEASURED DIFFERENCES IN GRAIN QUALITY Characteristic SRI (3 spacings) Conventional Diff. Chalky kernels 23.62 - 32.47 39.89 - 41.07 - 30.7 (%) General 1.02 - 4.04 6.74 - 7.17 - 65.7 chalkiness (%) Milled rice 53.58 - 54.41 41.54 - 51.46 + 16.1 outturn (%) Head milled 41.81 - 50.84 38.87 - 39.99 + 17.5 rice (%) Paper by Prof. Ma Jun, Sichuan Agricultural University, presented at 10th conference on Theory and Practice for High-Quality, High-Yielding Rice in China, Haerbin, 8/2004
  60. 60. SRI STILL RAISES MORE QUESTIONS THAN WE HAVE ANSWERS FOR • There are many researchable issues to be taken up by scientists, in association with farmers and with extension personnel • However, enough is known now to pursue a two-pronged strategy with (a) research and (b) practice proceeding in parallel
  61. 61. THANK YOU Email: ciifad@cornell.edu or tefysaina.tnr@simicro.mg Web page: http://ciifad.cornell.edu/sri/
  62. 62. Effects of SRI vs. Conventional Practices Comparing Varietal and Soil Differences 12 10 8 6 Local-Clay Local-Loam 4 HYV -Sand 2 Local-Sand 0 All SRI 1/4 SRI 2/4 SRI 3/4 SRI Practice Conv.