- 1. An Opportunity for Africa: The System of Rice
Intensification (SRI)[le Syst mede Riziculture Intensive] Norman
Uphoff, Cornell International Institutefor Food, Agriculture and
Development (CIIFAD) Cornell University, Ithaca, NY, USA
2. For Centuries, Even Millennia,We Have Been ABUSING and
MISTREATING the Rice Plant
- We have FLOODED it drowning itsroots
- We have CROWDED it inhibiting thegrowth potentialof its canopy
and roots
- Now we apply various FERTILIZERS and chemical BIOCIDES
affecting thesoil biotawhich providevaluable servicesto plants:N
fixation, P solubilization, protection against diseases and abiotic
stresses, etc.
3. SRI Offers an Opportunity to Raise Rice Production
Significantly
- Increasingyieldby 50-100% or more:
- Withoutchanging varietiesor requiring purchase of new seeds(any
variety works)
- Without requiringpurchase of fertilizersincecompostcan give
better results
- Using 25-50%less waterif irrigating rice, or adapting SRI
forrainfedcultivation
- No need foragrochemicalsbecause SRI plants are reasonably
resistant to pests and diseases
4. SRI Sounds Too Good to be True But It Offers Real
Advantages
- SRI utilizesbasic biological processes and dynamicsto evoke
amore productive PHENOTYPEfromany rice genotype
- It does this bychanging the waythat PLANTS, SOIL, WATER and
NUTRIENTS aremanaged changing practices that are centuries-old, but
yield-constraining
- SRI results can be explained based onsolid scientific knowledge
but we are not proposing itsadoption- only itsevaluation
5. Asingle rice plantgrown with SRI methods from a single seed
(Swarna), in Andhra Pradesh, India, 2003-04 season 6. Roots of
asingle rice plant(MTU 1071)grown at Agricultural Research Station
Maruteru, AP, India, 2003 season Roots are the key to SRI success
7. SRI field in Sri Lanka -- yield of 13 t/ha with some panicles
having 400+ grains 8. CFA Camilo Cienfuegos, Cuba 14 t/ha --
Variety Los Palacios 9 former yield on this field was 6 t/ha 9. SRI
field in Ambatovy, Madagascar with traditional variety 10. The
System of Rice Intensification
- Was evolved in Madagascar over 20 yrs byFr. Henri de Laulani,
S.J. working with farmers, observing, experimenting, also having
some luck in 1983-84 season
- SRI is now spreading in countries around the world: positive
results already in 21
- Association Tefy Sainawas set up in 1990 by Fr. de Laulani and
Malagasy friends to promote SRI and rural and human development in
Madagascar; ATS has been cooperating with CIIFAD since 1994
11. Fr. de Laulani not long before he died in 1995 12. Sebastien
Rafaralahy and Justin Rabenandrasana, president and secretary of
Association Tefy Saina 13. SRI in Summary :
- A set ofprinciples/methodsthat getmore productivePHENOTYPES
fromany existing GENOTYPEof rice.
- SRIchanges the managementofplants, soil, water, and
nutrients:
- (a) To induce greater ROOT growth
- (b) To nurturemore abundant and diversepopulations of SOIL
BIOTA
14. SRI Practices Should Always be Varied to Suit Conditions
- The fourbasic practicesof SRI:
- Young seedlings ( < 15 days ) are used though direct-seeding
is becoming an option
- Wide spacingsingle plants, in square pattern
- Soil aerationthru water management and weeding, so aerobic
conditions prevail in soil
- Organic matter is added to enhance the soil if enough compost
is used, fertilizer not needed
- Weed controlwith rotating hoe is recommended
15. Simple mechanical push-weeder called rotating hoe which
aerates the soil while it eliminates weeds 16. Weeding of SRI
fields in Madagascar, aerating the soil to stimulate root and plant
growth 17. All Organisms ArePhenotypes
- i.e., the result ofinteractionbetween genetic potential and
environment
- SRI practices change thegrowing environmentfor rice plants with
wider spacing to encourage growth of canopy and roots; aeration of
soil to encourage the growth of roots and soil organisms
- Most evidence ofphenotypical changecomes from Chinese research:
here are examples of research findings
18. Plant Physical Structure andLight Intensity Distributionat
Heading Stage (CNRRI Research --Tao et al. 2002) 19. Dry Matter
Accumulation between SRI and Control (CK) Practices(kg/ha) at
Maturity (Zheng et al., SAAS, 2003) 20. Table 2. Different Sizes of
the Leaf Blade (cm) with SRI Practices (Zheng et al., SAAS, 2003)
11.98 15.95 7.96 18.49 19.11 14.97 9.79 14.59 % 0.20 8.86 0.16 9.00
0.30 9.29 0.14 8.18 +/- 1.67 55.56 2.01 48.67 1.57 62.03 1.43 56.07
CK 1.87 64.41 2.17 57.67 1.87 71.32 1.57 64.25 SRI Width Length
Width Length Width Length Width Length Average Flag leaf 2 ndleaf 3
rdleaf Prac-tice 21. Figure 1. Change of leaf area index (LAI)
during growth cycle (Zheng et al., 2003) 22. Different P aradigmsof
Production
- The GREEN REVOLUTIONparadigm:
- (a) Changed thegenetic potentialof plants, and
- (b) Increased the use ofexternal inputs-- more water,
fertilizer, insecticides, etc.
- SRI changes certainmanagement practices for plants, soil, water
and nutrients, in order to:
- (A) Promotethe growth of root systems , and
- (B) Increase theabundance and diversityof
- soil organisms ,at the same time that they
- (C ) Reducewater use and cost of production
23. Greatest Benefit Is notYIELD
- Yield can vary, often widely; for farmers,profitabilityis more
important
- From societys perspective, what is most important isfactor
productivity kg of rice perland, labor, capital, and water
- No question any longer ofwhetherSRI methods give higher
yields/productivity but ratherhow to explainthese changes
- For some things, we haveevidence ; for others,strong
hypothesesfrom literature
24. SRI Results Reportedfrom Africa to Date 25. First Results,
thru 2002 Controlled trial 7.5 t/ha 1.6 t/ha Benin(2002) Same farms
7.4 t/ha 2.5 t/ha (10 farmers) The Gambia (2001) World Vision5.3
t/ha 2.5 t/ha (8 villages) Sierra Leone (2001) Max. yield of 21
t/ha 8 t/ha2 t/haNatl. ave. Madagascar (1990 - ) Comments SRI Yield
Comparison Yield 26. 27. More Recent ResultsControlled trials 9-11
t/ha 4-5 t/ha Senegal (2004) Thesis trials 3-8 t/ha (saline soil) 3
t/ha (good soil) Mozam-bique (2004) With hybrid rice 9.4 t/ha1.8
t/ha(natl. ave.) Guinea (2003) Comments SRI Yield Comparison Yield
28. What Are the Negatives? 29. There must be some, but they are
few:
- The main constraint has been SRI s initiallabor intensity while
farmers learn methods
- This isreceding as a constraint ; it is mostly a problem for
first several weeks or seasons
-
- GTZ evaluation in Cambodia (N = 400) showed little increase
(305 vs. 302 hrs/ha) -- and better timing
-
- IWMI evaluation in Sri Lanka (N = 120) showedlabor
productivityto be increased by 50-62%,with just partial use of SRI
methods;SRI labor pays
- Farmer innovationis helping to reduce labor requirements; more
innovations will come;SRI can even becomelabor savingover time
30. 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) 31. 4-row weeder designed by Gopal
Swaminathan, Thanjavur, TN, India 32. Seeder Developed in Cuba 33.
Other Negatives
- Water control is needed for best results --this constraint can
often be solved by better infrastructure and/or organizationSRI
will make such investmentspay
- Some yield improvement without water control
- F armer learning and skillare needed, but this is abenefitas
well as a cost
- Disadoptionhas been reported as a problem, but only in
Madagascar so far
- Nematodescan be a problem(e.g., Thailand)
34. SRI Has Been Called aNiche Innovation
- (Dobermann,Agricultural Systems , 2004) but there isno
systematic evidenceto support this claim
- CHINA: SRI is adding 2-3 t/ha to yields in the north
(Heilongjiong), south (Guizhou), east (Zhejiang) andwest
(Sichuan)
- INDIA: Similarly, SRI added 2-3 t/ha across all 22 districts in
Andhra Pradesh State, all having varying conditions
- SRI is not finished yet still evolving, still improving
- Already there are a number ofexplanationsthat are supported by
data or that can be hypothesized basedon the scientific
literature
35. Biological Explanations Not all of these may prove to be
correct -- but they provide more than enough scientific basis for
SRI credibility 36. 1 stExplanation? Above-Ground Environment
- SRI creates the edge effect for whole field
- Should avoid this only for measurement;should promote it
agronomically
- Too-close spacing affectsphotosynthesiswithin the canopy:
measurements in Indonesia found that with normal spacing,lower
leaveswere being subsidized by the upper leaves; wider spacing
enables thewhole plantto contribute
37. 2nd Explanation? Nitrogen Provision
- Rice yields were increased 40-60% when thesame amountof N is
providedequallyin both NO 3 andNH 4formsvs. whenall N is provided
as NH 4(Kronzucker et al.,Plant Physiol. , 1998)
- Biological N fixation(BNF) increases greatly with alternated
aerobic/anaerobic conditions (Magdoffand Bouldin,Plant and Soil ,
1970)
- Protozoacan contribute significantly to N supply (Bonkowski,New
Phytologist , 2004)
- Endophytes(bacteria living in plant tissues,as symbionts, not
parasites) also contribute
38. 39. 3rd Explanation?Phosphorus Solubilization
- This nutrient is often limiting factor, but
- Large amounts of P in soil (90-95%) are present in unavailable
form
- Alternating wetting and drying of soilincreased P in soil
solution by 85-1900%compared with soils just wet or just dry(Turner
and Haygarth,Nature , May 2001)
- Aerobic bacteria acquire P from unavailable sources during dry
phase; during wet phase theylyse and release P into the soil
solution
40. 4 thExplanation?Mycorrhizal Fungi
- 90+% of terrestrial plants derive benefits from and even depend
on mycorrhizal associations(infections)
- Mycorrhizal hyphae extend into soil and expand volume
accessible to the plant by10-100x ,acquiringwater, P and other
nutrients ; they also provide protective/other services to
plants
- Flooded riceforgoes these benefits
41. 5 thExplanation? Phytohormones
- Aerobic bacteria and fungi produceauxins, cytokinins,
gibberellins , etc. in the rhizosphere
- Huge literature has documented effects of microbially-produced
phytohormones (e.g., Frankenberger and Arshad, 1995)
- Root growth in SRI plants probably isnot due just to
physiological processeswithin the plants --stimulated by aerobic
microorganisms?Roots are key to SRI
42. Single Cambodianrice plant transplantedwhen 10-day-old
seedling 43. Cuba Two rice plants: same variety (VN 2084) and same
age (52days); 42 tillers on SRI plant vs. 5 tillers on the other
44. Dry Matter Distribution of Roots in SRI and
Conventionally-Grown Plants at Heading Stage(CNRRI research: Tao et
al. 2002) Root dry weight (g) 45. Table 13: Root Length Density
(cm. cm -3 ) under SRI, Modern (SRA) and Conventional Practice
(from Barison, 2002) Results from replicated on-station trials 0.06
0.13 0.36 1.19 1.28 4.11 Conventional practice 0.07 0.15 0.31 0.55
0.85 3.24 SRAwithout fertilization 0.09 0.18 0.34 0.65 0.99 3.73
SRAwith NPK and urea 0.20 0.25 0.32 0.57 0.71 3.33 SRI-- without
compost 0.23 0.30 0.33 0.61 0.75 3.65 SRI--with compost 40-50 30-40
20-30 10-20 5-10 0-5 Soil layers (cm) Treatments 46. Root
Oxygenation Ability with SRIvs. Conventionally-Grown Rice Research
done at Nanjing Agricultural University, Wuxianggeng 9 variety
(Wang et al. 2002) 47. Figure 8: Linear regression relationship
between N uptakeand grain yield for SRI andconventional
methods,using QUEFTS modeling (from Barison, 2002)Results are from
on-farm comparisons (N = 108) 48. Figure 9: Estimation of balanced
N uptake for given a grain yield for rice plants withthe SRI and
conventional systems,using QUEFTS modeling (same for P and K)
(Barison, 2002) Results are from on-farm comparisons (N = 108) 49.
Emerging Benefits from SRI These Should Be EvaluatedUnder Various
Circumstances 50.
- 1. Resistance toAbiotic Stressesthe climate is becoming more
extreme and more unpredictable, prepare for it
- Observed SRI resistance to
-
- drought (Sri Lanka, several years)
-
- hurricane (Sichuan Sept. 2002)
-
- typhoon (AP, India Dec. 2003)
-
- cold spell (AP, India February 2004)
- Resistance tolodgingprobably due to greater root growth --
roots degeneratein continuously flooded soil
51. Two rice fields in Sri Lanka -- same variety, same
irrigation system, andsame drought: conventional methods (left),
SRI (right) 52.
- 2. Resistance toPests and Diseases widely reported by farmers
this probably reflects theprotective servicesof soil
microorganisms
- 3. GreaterMilling Outturn ~ 15%:SRI paddy has66 to 75% higher
outturn in India; in Cuba, from 60 to 68-71%; adds to paddy
yield
- Fewerunfilled grains(less chaff)
- Fewerbroken grains(less shattering)
53. MEASURED DIFFERENCES IN GRAIN QUALITY CharacteristicSRI (3
spacings)ConventionalDiff. 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 + 17.5 38.87 - 39.99 41.81 - 50.84 Head milled rice (%) +
16.1 41.54 - 51.46 53.58 - 54.41 Milled rice outturn (%) - 65.7
6.74 - 7.17 1.02 - 4.04 General chalkiness (%) - 30.7 39.89 - 41.07
23.62 - 32.47 Chalky kernels (%) 54. Emerging Benefits of SRI?
- 4. HigherNutritional/Health Value ?
- SRI can be organic rice that is free from agrochemical
residues
- Possibly SRI has higher nutritional quality in terms
ofmicronutrients this should be evaluated scientifically
- Larger root systems give higher grain weight and greater grain
density, soalso greater nutrient density?
55. Emerging Benefits of SRI?
- 5. Conservation of RiceBiodiversity ?
- Highest SRI yields come with HYVs and hybrids (all SRI yields
>15 t/ha)
- Buttraditional/local varietiesrespond very well to SRI
practice; can produce yields of 6-10 t/ha, and even more
- Traditional rices receivehigher price; higher yield with SRI
makes them popular
- Get anorganic premiumfor export?
56. 57. LESSCAN PRODUCEMORE
- byutilizingbiological potentials & processes
- Smaller, younger seedlings becomelarger, more productive mature
plants
- Fewer plants per hill and per m 2will givehigher yieldif used
with other SRI practices
- Half as much water producesmore rice because aerobic soil
conditions are better
- Greater outputis possiblewith use of
- fewer or evenno external/chemical inputs
- Changes in management practices givedifferent phenotypes
fromrice genomes
58. SRI STILL RAISESMORE QUESTIONSTHANWE HAVE ANSWERS FOR
- There are many researchable questions to be taken up by
scientists, in association with farmers and extension
personnel
- But enough is known to pursue atwo-pronged strategy : research
and practice can proceedin parallel
59. Evaluating SRI Should be Low-Cost and without Any Evident
Hazards
- SRI requires no purchases to try(except rotating hoes if
possible) justchanges in practices
- No chemicals are used, and there is no genetic modification
involved
- SRI can be tested and demonstrated on a small part of farmers
fields guarantee can be given of no loss
60. SRI Experience Could HelpImprove 21 stCentury
Agriculture
- Nurturing of roots and soil biota is relevant for much of
agriculture
- We need an agriculture that is
-
- Less thirsty-- better roots will help
-
- Less dependent on fossil-fuel energysources -- fertilizer,
mechanization
-
- Less dependent on agrochemicals--for sake of soil & water
quality, for health
61. SRI Concepts Have Been Extrapolated toUpland Rice
- In Madagascar, using mulch after directly planted seeds had
emerged (plus wider spacing, organic inputs, etc.), an unirrigated
yield of4 t/haobtained on farmers field in 1999
- In Philippines, similar methods without chemical fertilizer
obtained average yield of7.2 t/hain 2002 on an upland unirrigated
area of 4000 m 2
62. SRI CONCEPTS CAN BE EXTENDED TOUPLAND PRODUCTION Results of
trials (N=20) by the Philippine NGO,Broader Initiatives for Negros
Development, withAzucenalocal variety (four replications -- 4,000 m
2area, usingmulchas main innovation, not young plants) 63. CAN WE
CONTINUE TO RELY SO HEAVILY ON N FERTILIZE? To raise world rice
production by 60% by 2030,N fertilizer applications will need to be
tripledbecause ofdiminishing returnsto fertilizer use(Cassman et
al., 1998)
- Who believes this isfeasible ?
- Who believes this isdesirable ?
- Would it beeconomically possible ?
- Would it beenvironmentally sustainable ?
- SRI suggests that dependingmore on biology and less on
chemistry may be effective at least this option should be
investigated
64. 65. SRI Data from Sri Lanka
- Yields(tons/ha) 8.0 4.2+88%
- Market price(Rs/ton) 1,500 1,300 +15%
- Total cash cost(Rs/ha)18,000 22,000-18%
- Gross returns(Rs/ha) 120,000 58,500+105%
- Net profit(Rs/ha) 102,000 36,500+180%
- Family labor earnings Increased with SRI
- Data from Dr. Aldas Janaiah, IRRI agric. economist, 1999-2002;
now at Indira Gandhi Development Research Institute in Mumbai;
based on interviews conducted with 30 SRI farmers in Sri Lanka,
October, 2002
66. IWMI Data from Sri Lanka
- IWMI Evaluation (Namara, Weligamage, Barker 2004)
- 60 SRI and 60 non-SRI farmers randomly selected:
- YIELD-- increased by 50% on average,not doing full SRI
- WATER PRODUCTIVITY-- increased by 90%
- COST OF PRODUCTION(Rs./kg) -- lower by 111-209% with family
labor, 17-27% at standard wage rate
- LABOR PRODUCTIVITY(kg/hr) -- up 50% in yala (dry) season, and
up 62% in maha (wet) season
- PROFITABILITY-- increased by 83-206%, depending on the wage
assumed (family labor vs. paid labor)
- RISK REDUCTION-- conventional farmers had net losses in 28% of
seasons, SRI farmers in only 4%
67. Contribution of SOIL MICROBIAL PROCESSES
- Microbial activity is known to be a crucial factor in soil
fertility
- The microbial flora causes a large number of biochemical
changes in the soil thatlargely determine the fertility of the
soil. (DeDatta,1981, p. 60, emphasis added)
68. Bacteria, funguses, protozoa, amoeba, actinomycetes,
etc.
- Decompose organic matter , making nutrients available
- Acquire nutrients otherwise unavailable to plant roots
- Improve soil structure and health -- water retention, soil
aggregation, aeration, pathogen control, etc.
69. PHYLLOCHRONS
- The reason whytransplanting young seedlingsenhances crop yield
is that transplanting should occurduring the 2 ndor 3 rdphyllochron
of growth , before tillering and root growth begin their
acceleration.
- Transplantingafter about the 15 thdaywill cause greater trauma
to the plant and affect its growth trajectory.
70. CAREFUL TRANSPLANTING
- Is akey elementof SRI methodology
-
- from beinguprooted crudelyfrom nursery,
-
- from beingleft in the sunto dry (dessicate),
-
- from havingsoil knocked of the roots ,
-
- from being planted inhypoxic flooded soil
- reduces growth potential of the plants
- Gentle, careful transplantingis crucial,not inverting the root
tip upwardsas this delays the resumption of growth
71. PHYLLOCHRONS
- were discovered in 1920s and 1930s by a Japanese scientist,T.
Katayama
- They arean interval of plant growth , found in all grass family
grains (rice, wheat, etc.) a repeating period in whichone or more
phytomers(units of a leaf, a root and a tiller) emerge from the
apical meristem
- Fr. de Laulanie came serendipitously upon the value of
transplanting during the window of opportunity during 2 ndor 3
rdphyllochron to capitalize on the rice plants full potential
72. 73. 74. Effects of SRI vs. Conventional Practices Comparing
Varietal and Soil Differences 75. Spread of SRI in Asia 76. Spread
of SRI in Africa
- Madagascar : now 50,000-100,000 farmers,average about 6-8 t/ha,
some double or more
- Sierra Leone : 2.55.3 t/ha for 160 farmers
- The Gambia : 2.57.4 t/ha for 10 farmers
- Benin : 1.67.5 t/ha in controlled trial
- Guinea : 2.59.4 t/ha (hybrid + SRI)
- Mozambique:good soils 3saline soils 3-8 t/ha
- Senegal:4-59-11 t/ha (FAO trials)
- Interest in, but no results yet from: Ethiopia, Ghana, Mali,
South Africa, Tanzania, and Uganda
77. Spread of SRI in Latin America
- Cuba : average 8-9 t/ha; INCA trial 12 t/ha;a number of farmers
have reached 14 t/ha
- Peru : initial problems with drought, frost; 2003 results 9-11
t/ha vs. current average of6 t/ha ( not profitable given costs of
production)
- Interest in, but no results yet from: Barbados, Brazil,
Colombia, Dominican Republic, Guyana, Haiti, Trinidad, and
Venezuela
78. 79. 80. 81. 82. 83. . 84. 85. Contact Information
- SRI home page on the Internet/Web:http://
ciifad.cornell.edu/sri /
- E-mail communication:[email_address](esp. French)
- [email_address](esp. English)