The System of Rice Intensification (SRI):

An Opportunity to Improve Food Security with Water-

Saving Benefits

Norman Uphoff, CIIFADCornell University, USA

SRI Experience Is SpreadingComparison Yields (t.ha-1) vs. SRI Average and Max.Country Comp. Yields Ave. SRI Yields Ave. SRI Maximum

BANGLADESH 4.9 6.3 7.1CAMBODIA 2.1 4.4 8.5CHINA (hybrids) 10.9 12.8 14.8CUBA 6.2 9.8 12.7GAMBIA 2.3 7.1 8.8INDONESIA 4.8 8.2 9.0LAOS 3.3 3.3 7.0MADAGASCAR 2.6 7.2 13.9NEPAL 4.4 8.1 11.1PHILIPPINES 3.0 6.0 7.4SIERRA LEONE 2.6 5.3 7.4SRI LANKA 3.6 7.8 14.3

Average 3.9 7.0 10.1

Average Yields Impressive --But Big Increases Very Surprising

Indonesia -- West Timor (ADRA) • Yield with current methods -- 4.4 t/ha• Yield with SRI methods -- 11.7 t/haPeru -- Pucallpa, jungle area• Previous yields -- 2 t/ha, with more labor• SRI yield -- 8 t/ha, with less labor + ratoon crop 5.5 t/ha = 70% of first cropBenin -- controlled trials: 1.6 vs. 7.5 t/ha

Experience in West Africa

• SIERRA LEONE: World Vision/SL sent agricultural staff member to Madagascar in 2000; 8 villages (160 farmers) did trials: average yield 5.3 t/ha vs. 2.5 t/ha

• THE GAMBIA: Former director of Sapu Research station did trials there in 2000: 5.4-8.3 t/ha results; field day for farmers on-farm trials in 2001, divided fields (N=10) gave yields of 7.4 t/ha vs. 2.5 t/ha

SRI Data from Sri Lanka SRI Usual

• 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

• Water savings ~ 40-50%

Data from Dr. Janaiah Aldas, an economist formerly with IRRI; now at Indira Gandhi Development Research Institute, Mumbai; based on interviews with 30 SRI farmers in Sri Lanka, October, 2002

SRI IDEAS CAN BE ADAPTED TO UPLAND PRODUCTION

Results of Trials (N=20) by Philippine NGO [Broader Initiatives for Negros Development] with Azucena Local Variety ( 4,000 m2 area )

Spacing Tillers/Hill

PanicleLength

Grains/Panicle

Yield(t/ha)

Net Return(P)

15x40 7.2 30.4 331.2 7.4 2.520x40 9.9 29.4 338.1 7.7 2.925x40 10.2 28.2 315.5 7.4 2.730x40 9.7 29.8 374.9 7.0 2.635x40 11.4 29.2 364.5 6.7 2.4

SRI changes production paradigm

• GREEN REVOLUTION paradigm:(a) Changes plants’ genetic potential, and(b) Provides plants with chemical-intensive external inputs -- fertilizer, biocides, etc.

• SRI changes certain management practices:(a) To promote root growth, and(b) To increase the abundance and diversity

of soil microbial populations

PROMOTION OF ROOT SYSTEMS

• SRI is becoming referred to in India as ‘the root revolution’

• Roots benefit from wider plant spacing, aerated soil, and more soil organic matter (compost + root exudation)

• Roots are supported by more abundant and diversified populations of soil biota

• Plants are two-way streets, coevolved w/ microorganisms, dependent on them

Cuba: Variety 2084 (Bollito) -- 26 DAP

Cuba -- Variety 2084 (Bollito) -- 52 DAP

Dry Matter Distribution of Roots in SRI and Conventionally-Grown Plants at

Heading Stage (CNRRI research: Tao et al. 2002)

Root dry weight (g)

Root Activity in SRI and Conventional Rice Measured by Oxygenation Ability

Research at Nanjing Agricultural University,Wuxianggeng 9 variety (Wang et al. 2002)

0

100

200

300

400

500

N-n n-2 Heading Maturity

Development stage

Ox

yg

en

ati

on

ab

ilit

y o

f α -

NA

(ug

/h.g

DW

)

W

S

SRI farmer in Cambodia

SRI farmer in Cuba -- 14 t/ha

Research Reported by Dr. Ana Primavesi (1980)

Shoot and root growth (in g) of maize grown in hydroponic solutions (14 days), with varying nutrient concentrations

Shoot Root100% concentration 44 7

200% concentration 34 7

2% concentration 33 23

2% concentration 43 56 changed every other day

Contribution of SOIL MICROBIAL PROCESSESMicrobial activity is known to be

crucial for soil fertility

“The microbial flora causes a large number of biochemical changes in the soil that largely determine the fertility of the soil.” (DeDatta, 1981, p. 60, emphasis added)

Bacteria, funguses, protozoa, amoeba, actinomycetes, etc.

• Decompose organic matter, making nutrients available

• Acquire nutrients that are unavailable to plant roots

• Improve soil structure and health (water retention, soil aggregation, pathogen control, etc.)

Known Processes

• Biological nitrogen fixation (BNF) **

• Phosphorus (P) solubilization **

• Nutrient acquisition through mycorrhizal fungus associations with roots

• Contribution of growth-promoting hormones from rhizobia bacteria

• Protozoan ‘grazing’ of bacteria on roots, excreting excess N

** Increased by wetting and drying of soil

AZOSPIRILLUM POPULATIONS, TILLERING AND RICE YIELDS ASSOCIATED WITH DIFFERENT CULTIVATION PRACTICES

AND NUTRIENT AMENDMENTSResults of trials at the Centre for Diffusion of Agricultural Intensification,

Beforona, Madagascar, 2000 (Raobelison, 2000)

Azospirillum in the

CLAY SOIL Rhizosphere(103/ml)

Roots(103/mg)

Tillers/plant

Yield(t/ha)

Traditional cultivation,no amendments

25 65 17 1.8

SRI cultivation, withno amendments

25 1,100 45 6.1

SRI cultivation, withNPK amendments

25 450 68 9.0

SRI cultivation, withcompost amendmts

25 1,400 78 10.5

LOAM SOILSRI cultivation, withno amendments

25 75 32 2.1

SRI cultivation, withcompost amendmts

25 2,000 47 6.6

Impact of Transplanting YOUNG SEEDLINGS

• Significant effect from transplanting 8-12 day-old seedlings = during the 2nd or 3rd phyllochron (explained by work of Katayama, 1920s-30s)

• Avoid trauma to rice plant, esp. to its roots, for max. growth trajectory

• DIRECT SEEDING is possible

Effect of Young Seedlings@ Anjomakely Clay Soil Loam Soil

SS/20/3/NPK 3.00 2.04

SS/ 8 /3/NPK 7.16 3.89

SS/ 8 /1/NPK 8.13 4.36

AS/ 8 /3/NPK 8.15 4.44

AS/ 8 /3/Comp 6.86 3.61

SS/ 8 /1/Comp 7.70 4.07

AS/ 8 /1/NPK 8.77 5.00

AS/ 8 /1/Comp 10.35 6.39

Conclusions• New, more productive paradigm is

emerging from practice around world

• Need to reduce current dependence on external (chemical) inputs

• Importance of looking and working below ground -- at roots + soil biology

• Soil depletion or exhaustion can be offset by creating ‘open systems’ supported by the power of biology

Thank You for Opportunityto Share this With You

• More information can be obtained from SRI web site:– http://ciifad.cornell.edu/sri/

• Or from Association Tefy Saina:– tefysaina.tnr@simicro.mg

• Or from me:– ntu1@cornell.edu

Effects of SRI vs. Conventional PracticesComparing Varietal and Soil Differences

0

2

4

6

8

10

12C

onv.

Pra

ctic

e

1/4

SRI

2/4

SRI

3/4

SRI

All

SR

I

Local-ClayLocal-LoamHYV -SandLocal-Sand