The System of Rice Intensification (SRI):

AdvantagesCornell International Institute for Food, Agriculture

and Development (CIIFAD)

and Association Tefy Saina, Madagascar

I. Advantages of SRI beyond Yield Increases

Yield is Most Evident Advantage• Yield is most obvious and visible benefit• Increased number of tillers and larger

and more panicles can be counted and measured; yield is simple and impressive

• But higher yield at high cost may be of no real benefit

• It is greater productivity of resources that makes farmers and countries richer

• SRI is more about productivity than yield and also provides many other benefits

SRI Yield Gains Are Significant• The following table summarizes data from a

French development assistance project to improve small-scale irrigation schemes on the high plateau of Madagascar

• There was no significant extension effort to promote SRI in the area. Most of the spread was farmer-to-farmer based on results

• SRA is a more input-intensive method for rice growing, promoted by the government

• Very similar to results from Morang district, Nepal, from two years of evaluation there

Other Benefits to Be Considered• 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• Resistance 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

A. Cost Reduction andIncreased Profitability

• Water saving can be 25-50%• Seed reduction should be 80-90%• Fertilizer can become unnecessary as

homemade compost can be even better • Purchase of pesticides can be reduced

or becomes unnecessary• Labor saving is possible after 1st year• All these savings reduce cost per kg

of rice produced• All this gives farmers more profit

Evaluation in Tamil Nadu, India

• 100 on-farm Adaptive Research Trials, each with two 1,000 m2 plots, one with SRI methods, one with farmer practices

• Not all practices used as recommended (only 36), but all used 14-day seedlings– FP yield average 5,657 t/ha (3,887-8,730)– SRI average 7,227 t/ha (4,414-10,655)– 31 SRI yields > 8 t/ha -- only 3 FP yields

• SRI average yield only 27.8% over FP but still major economic improvements

COSTS OF CULTIVATION PER HECTARE

Activity

Tractor (hrs) @ Rs. 150 /

hr hr

Bullock pair @ Rs. 200 /

Men’s Labor

@ Rs. 40 / day

Women’s Labor

@ Rs. 40 / dayCost (Rs.)

FP SRI FP SRI FP SRI FP SRI FP SRI

Nursery preparation 1 - - - 6 3 0.5 5.5 2110 681

Main field preparation

7.5 7.5 2 2 12 12 - - 2005 2005

Manures & fertilizers

- - - - 7 7 10 10 7254 7254

Transplanting - - - - 5 5 55 75 2400 3200

Weeding - - - - - 38 80 - 3200 1520

Irrigation - - - - 7.5 6 - - 300 240

Plant protection - - - - 2 2 2 2 660 660

Harvesting 1 1 - - 12.5 12.5 75 75 3500 3500

Total 9.5 8.5 2 2 52 85.5 222.5 167.5 21,429 19,060

Saving of SRI over conventional system = Rs. 2,369 (11 %)

ECONOMIC EVALUATION (US$/ha) Farmer practice

SRI practice

Income from grain (Rs. 5.00 / kg) $ 659 $ 870

Income from straw(Rs. 0.25 / kg) $ 49 $ 63

Gross return $ 708 $ 933

Cost of cultivation $ 466 $ 414

Net return $ 242 $ 519

Benefit : Cost ratio 1.52 2.25

This is not a ‘best case’ evaluation

• Since not all SRI methods were being used; usually SRI can raise yield by 50% or more

• Even so:– Costs of production were reduced by 11%– with labor inputs reduced by 7% (1st year)– and water savings were 40-50%– Farmers’ net income per hectare was

increased by 110% with partial SRI methods

Evaluations in Sri Lanka and Cambodia(Namara et al., 2003; Anthofer et al., 2004)

• IWMI: In Sri Lanka, 60 SRI users and 60 non-SRI users were randomly selected in 2 districts:– Average yield went up 42-56% depending on season– Farmer profitability of rice production more than doubled,

with some variance by season– Data did not show reduced total cost of production, but

cost of production (Rs./kg of rice) went down by 21.5%• GTZ: In Cambodia, 400 SRI users, 100 non-SRI

users were chosen at random in 5 provinces:– Average yield was increased by 41%– Farmers’ net margins/ha were raised by 74%– Variable costs of production went down by 56.5%

In neither were ‘SRI users’ using all the SRI practices recommended, or using them all as recommended

Evaluations in Bangladesh

• Coordinated by BRAC and supported by PETRRA project, funded DFID and managed by IRRI/Bangladesh

• Two seasons, 2002-03 and 2003-04

• Not all recommended practices used, but:– Tillers/hill up 95% and 60% in these years,– Effective tillers up 94% and 122%– Grain weight up 14-18% per 100 grains

• Yield increase of 26.6%; net returns/ha up 60%

Yield Results: Bangladesh Evaluations

Figure 1. Comparative yield of rice under SRI and farmers' practices by partner organisations, 2002-03

6.3

4 7.0

3

6.1

5.9

5.2

5 5.9

4.7

8.1

0

1

2

3

4

5

6

7

8

9

10

BRAC POSD SAFE Syngenta

Yie

ld (

t/h

a)

SRI Farmers' practice

Farmer Net Returns: Bangladesh Evaluations

4526

2

3825

7 4210

0

2776

5

2486

3

2412

0 3186

5

1665

5

0

10000

20000

30000

40000

50000

BRAC POSD SAFE Syngenta

Net r

etur

n (T

k/ha)

SRI Farmers' practice

Economic Evaluations Are More Useful than Agronomic Comparisons

• Few innovations have come along in the rice sector that can give farmers similar improvement in yields

• That SRI increases can be achieved with lower cost means that the economic gains are even greater

• In addition, there are social and environmental benefits to be considered

B. Lower Capital Requirements Making SRI More Accessibleto Low-Income Households

SRI Is Considered Relatively More Labor-Intensive

• Capital expenditures can be reduced because of no need to purchase fertilizers or other agrochemicals

• Only purchase advised in rotating hoe or cono-weeder (~ $10-15)

• SRI productivity gains can pay off this investment in one season

• Credit or supply may be a problem

Labor-Intensity Has Been Seen as a Constraint for Poor

• Evaluation of SRI in Madagascar by Moser and Barrett (2003) concluded that despite SRI advantages of higher productivity, poor households could not afford to use its methods because of cash flow constraints – needing to earn income from labor on a daily/weekly basis to survive – could not afford to wait 3 months

• If this is a problem, the fault lies in institutional failures -- to provide reasonable access to credit -- rather than in the SRI methods themselves

• Disadoption rates of 40% were reported in Moser-Barrett study

• GTZ evaluation did not find labor-intensity or disadoption to be problem in Cambodia (number of SRI users has gone from 28 to 15,000 in four years)

Labor-Intensity Is Not Much of a Problem

• As SRI is turning out not to be labor-intensive over time -- and not always to be more labor-intensive even at the outset – so this concern is receding

• IWMI study found poor farmers were as likely to adopt SRI as richer farmers, and more likely to continue with SRI once they had adopted it (Namara et al., 2003)

• Yield and income gains should help make poor households more food-secure

C. Resistance to Pests and Diseases

Repeated Reports from Farmers

• SRI crops are “more resistant to pests and diseases – no need to spray”

• This aspect of SRI has been less studied– though 2001 report from IPM farmer group

in Ciamis, Indonesia, showed higher beneficial:predator insect ratio in SRI plots

• Tamil Nadu Agricultural University study has provided data confirming farmers’ observations

Insects and their damage /

population

SRI cultivation

(Mean ± SE)

Conventional cultivation

(Mean ± SE)

t value

Cut worm(% damaged leaves)

0.0 ± 0.0

(0.0)

20.4 ± 4.8

(19.1)

16.1**

Thrips 0.5 ± 0.2

(0.9)

6.1 ± 0.5

(2.5)

19.3**

Green leaf hopper

0.1 ± 0.0

(0.8)

0.4 ± 0.1

(0.9)

14.8**

Brown plant hopper

0.0 ± 0.0

(0.0)

0.2 ± 0.0

(0.8)

11.5**

Whorl maggot(% damaged leaves)

0.8 ± 0.2

(0.9)

9.3 ± 2.6

(9.1)

12.5**

(Figures in parentheses are transformed values) ** Significant difference (T <0.001)

Pest abundance in nursery (per seedling)

Insects and their damage /

population

SRI cultivation(Mean ± SE)

Conventional cultivation(Mean ± SE)

t value

Whorl maggot(% damaged leaves)

17.9 ± 1.9

(18.0)

23.2 ± 2.0

(19.1)

6.6**

Thrips 6.6 ± 0.1

(2.2)

20.2 ± 2.0

(4.1)

12.2**

Green leaf hoppers

0.6 ± 0.1

(1.0)

1.1 ± 0.2

(1.2)

10.7**

Brown plant hoppers

1.1 ± 0.2

(1.2)

2.7 ± 0.2

(1.8)

14.4**

Whorl maggot(% truncated leaves)

5.6 ± 1.8

(5.9)

8.8 ± 1.4

(9.1)

4.5**

(Figures in parentheses are transformed values) ** Significant difference (T <0.001)

Pest abundance in main field (per hill)

Insects and their damage /

population

SRI cultivation(Mean ± SE)

Conventional cultivation(Mean ± SE)

t value

Gall midge(% silver shoot)

5.0 ± 1.2

(6.8)

11.0 ± 1.5

(19.1)

9.3**

Stem borers(deadheart/white

ear)

11.7 ± 1.3

(15.5)

7.3 ± 1.0

(10.0)

10.1**

Leaf folder(scraped leaves)

20.3 ± 1.6

(21.7)

6.5 ± 1.0

(11.8)

15.4**

Earhead bugs 0.9 ± 0.1

(1.1)

0.9 ± 0.1

(1.1)

0.4NS

(Figures in parentheses are transformed values) ** Significant difference (T < 0.0001)

Pest abundance in main field (per hill)

D. Resistance to Climatic Effects

‘Abiotic Stresses’ Are Major Threats to Rice Crops

• ‘Extreme events’ due to unexpected variations in rainfall and temperature becoming more common, whether or not there is global warming

• DROUGHT is a major problems for rice farmers

• SRI plants after about 1 month become resistant to drought

Two rice fields in Sri Lanka -- same variety,same irrigation system, and same drought :

conventional methods (left), SRI (right)

Storm Damage Is Also a Major Problem for Rice Farmers

• SRI rice crops have resisted:– Typhoon damage (Meishan, Sichuan,

China, September 2002)– Cyclone damage (Andhra Pradesh,

India, December 2003)– Cold spell (Andhra Pradesh, India,

February 2004)

• Young SRI plants do not resist flooding, however

Non-lodged SRI crop above,

in Tamil Nadu, India

E. Environmental Benefits

These Benefits Not Yet Documented

• Environment will surely benefit from a reduction in rice sector’s demand for water -- less problems for farmers too

• Water quality will improve with reduced use of N fertilizer with less nitrate (NO3) in groundwater and fewer chemicals --also better for farmers’ health

• With no flooding of rice fields, reduce methane and other greenhouse gas emissions (offset by NO2?) – need study

F. Lower Farmers’ Risk

SRI Appears More Risky• For first month or so, SRI paddy field

looks terrible!– Only a few small plants can be seen: no

beautiful green field as farmers expect– Field is brown mud, not flooded so that

the blue sky is reflected

• Small seedlings appear vulnerable, but with good nursery growth, in an unflooded field they are very hardy

SRI Can Reduce Risk• By raising yields on average, and at the same

time reducing costs of production, farmers have less risk with SRI:– The IWMI evaluation found that Sri Lankan farmers

had net economic losses in about 2% of their seasons, compared with 17% of their seasons growing rice with conventional methods

– The GTZ found that the risk of not meeting production targets was greatly reduced for SRI farmers in Cambodia

• These economic analyses are reinforced by the reduction in losses from biotic or abiotic stress that SRI methods make possible

G. Higher Grain Quality

SRI Advantages Are More than Quantity• In this area also, we have more farmer

reports than scientific evaluations

• There is evidence that milling outturn is higher from SRI paddy rice due to:– Fewer unfilled grains (less chaff), and– Fewer broken grains (less shattering)

• There are also reports of better eating qualities and better keeping quality after cooking

• Some evidence is available from China

MEASURED DIFFERENCES IN GRAIN QUALITY Characteristic SRI (3 spacings) Conventional % Diff.

Chalky kernels (%)

23.62 - 32.47 39.89 - 41.07 - 30.7

General chalkiness (%)

1.02 - 4.04 6.74 - 7.17 - 65.7

Milled rice outturn (%)

53.58 - 54.41 41.54 - 51.46 + 16.1

Head milled rice (%)

41.81 - 50.84 38.87 - 39.99 + 17.5

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, 8/26/2004

Grain Quality Will Be Increasingly Important

• Consumers are becoming more concerned with quality

• Rice is losing demand as mass food

• SRI enables farmers to get high yield of ‘organic’ rice, for higher premium? Chemical-free rice is more healthy

• Given larger root system taking up more micronutrients, SRI could be more nutritious, but no evidence yet

H. Biodiversity Conservation

Unexpected Benefit• SRI methods raise the yields of both

‘modern’ varieties of rice – high-yielding varieties (HYVs) and hybrids– All the highest SRI yields (> 15 t/ha)

have been with ‘modern’ varieties

• But ‘traditional’ varieties respond well – with yields in 5-12 t/ha range– Because the market price for such

varieties is higher (2-3x), growing them can be very profitable -- even more than growing ‘modern’ varieties

Rice Biodiversity Is Being Reduced by New Varieties

• SRI can make it attractive for farmers to conserve their traditional varieties – local landraces

• CIIFAD has started a collaborative initiative with NGOs and farmer groups in Cambodia, Madagascar and Sri Lanka to promote ‘organically-grown’ indigenous rice varieties – for local sale and for export – at higher prices

Biodiversity Conservation Will Benefit Plant Breeding

• Conserving the genetic inheritance of rice species will make it possible to continue breeding improved varieties, though for other qualities than maximum yield

• Hybrid varieties give even higher yield with SRI methods, and much less seed is required, so SRI makes this innovation more attractive too

I. Diversification and Modernization of Agriculture

SRI Is Not Just for Producing More Rice

• The world does not need as much rice as can be produced with SRI methods

• SRI, as noted at the start of this presentation, is mostly concerned with PRODUCTIVITY

• Too much of the world’s land, labor, water and capital is currently devoted to rice production

• We will be better off if staple food needs can be met with fewer of these resources, so that more of them can be devoted to other kinds of production

Intensification Should Support Diversification

• We aim to meet with world’s basic food needs and ensure food security with fewer resources

• Increased efficiency and productivity will lower the price of rice, which will benefit the urban poor

• More diversified farming operations will improve both incomes and nutrition

Intensification Should Support Modernization

• SRI is expected to help farmers become better managers and decision-makers, more involved in experimentation and evaluation and in making changes

• SRI supports more ecological approach to agriculture, with knowledge-based development, focused on the potentials of biology

• 21st century = ‘the century of biology’ ?

SRI STILL RAISES MORE QUESTIONS THAN WE HAVE

ANSWERS FOR• Enough is known now to pursue a two-

pronged strategy with research and practice proceeding in parallel

• There are many researchable issues to be taken up by scientists in association with farmers and extension personnel – what is important is that new knowledge be widely shared

THANK YOU

Email: ciifad@cornell.eduor tefysaina.tnr@simicro.mg

Web page: http://ciifad.cornell.edu/sri/

Addendum: Phyllochrons