Opportunities for Raising Rice Yields and Factor Productivity

with the System of Rice Intensification (SRI)

from Madagascar

Norman Uphoff, CIIFADCREES Seminar, Washington

October 30, 2004

SRI is controversial in some circles But it is not a ‘niche innovation’ as stated by Dobermann

in Agricultural Systems (2004); nor is it ‘voodoo science’ as suggested by Cassman and Sinclair, ACSSA (2004)

Sheehy et al. maintain in Field Crops Research (2004) that: “[SRI] has no major role in improving rice production

generally” -- but this is an untenable conclusion, unsupported by any systematic evidence, and with much evidence that contradicts it, esp. from China

Sinclair (USDA) wrote: “Discussion of SRI is unfortunate because it implies SRI merits serious consideration. SRI does not deserve such consideration.” Rice Today (2004)

However, SRI is making large differences in yields and in factor productivity in many countries – spreading rapidly

We want it to be scientifically evaluated – preferably with farmers [usually better results on-farm than on-station]

SRI Message: For Centuries, Even Millennia, We Have Been ABUSING and MISTREATING the Rice Plant

• We have FLOODED it – drowning its roots• We have CROWDED it – inhibiting the growth

potential of its canopy and roots• Now we apply FERTILIZERS and chemical

BIOCIDES that adversely affect soil biota which provide many services to plants: N fixation, P solubilization, protection against diseases and abiotic stresses, etc.

SRI Results are Remarkable,but Have Been Replicated Widely

• Yield increases – 50-100% or more, with• No change in varieties – all give increase, and

no need for mineral fertilizers – they are beneficial; compost gives better yield

• Little or no need for agrochemicals -- SRI plants more resistant to pests/diseases

• Reduced seed requirement – by 80-90% and less water requirement – by 25-50%

• More labor is required initially, but SRI can even become labor-saving over time

SRI rice field, hybrid variety, Yunnan province, 2004 – 18 t/ha

Cambodian farmerwith rice plant grown

from single seed,using SRI methods

and traditional variety

Madagascar SRIfield -- 2003

SRI field in Cuba-- 2003CFA Camilo Cienfuegos14 t/ha – Los Palacios 9

SRI field in Sri Lanka – with many panicles having 400+ grains

The System of Rice Intensification

• Evolved in Madagascar over 20 years by Fr. Henri de Laulanié, S.J. – working with farmers, observing, doing experiments, also having some luck in 1983-84 season

• SRI is now spreading around the world: positive results now seen in 21 countries

• SRI is a set of principles and insights that when translated into certain practices can change the growing environment of rice to get healthier, more productive plants representing different phenotypes

Fr. de Laulaniémaking field visit

Sebastien Rafaralahy andJustin Rabenandrasana,Association Tefy Saina

SRI is a set of principles and methods to get more productive

PHENOTYPES from any GENOTYPE

SRI changes the management of plants, soil, water, and nutrients to:

(a) induce greater ROOT growth and

(b) nurture more abundant and diverse populations of SOIL BIOTA

Capitalize on existing rice potentials

Swarna under SRICanopy of an individual rice plant grown under SRIconditions; usually this variety (Swarna) is ‘shy-tillering’

Andhra Pradesh, India, rabi season, 2003-04

Roots of a single rice plant (MTU 1071) grown at Agricultural Research Station

Maruteru, AP, India, kharif 2003

Different Paradigms of Production • The GREEN REVOLUTION paradigm:

(a) Changed the genetic potential of plants, and

(b) Increased the use of external inputs -- more water, fertilizer, insecticides, etc.

• SRI changes certain management practices for plants, soil, water and nutrients, so as to:

(A) Promote the growth of root systems, and

(B) Increase the abundance and diversity of

soil organisms, and also (C) Reduce water use and costs of production

21st Century Agriculture Should Be• More PRODUCTIVE AGRONOMICALLY:

– LAND -- per unit area -- per ha or per acre– LABOR -- per hour or per day– WATER -- per cubic meter or per acre/ft– CAPITAL -- more profitable for $ invested

• More ENVIRONMENTALLY BENIGN– More robust in face of CLIMATE CHANGE

• More SOCIALLY BENEFICIAL– ACCESSIBLE to the poor, reducing poverty– Providing greater FOOD SECURITY– Contributing more to HUMAN HEALTH

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Changes in Fertilizer Use

World Grain Production (mmt)

Fertilizer Use (mmt)

Marginal Response Ratio

Decade Δ Decade Δ

1950 631 14 --

1961 805 (+174) 31 (+17) 10.2:1

1969-71 1116(+311) 68(+37) 8.4:1

1979-81 1442(+326) 116(+48) 6.8:1

1989-91 1732(+290) 140(+24) 12.1:1

1999-01 1885(+153) 138(-2) ?

‘Modern agriculture’ is not necessarily the ultimate form of agriculture

• Productivity gains achieved with heavy use of external inputs are slowing down

• Negative side-effects are becoming more evident -- environmental, social costs

• Can we make further progress in the 21st century by doing ‘more of the same’?

• Doubtful because of diminishing returns -- in case of rice (K. Cassman et al., 1998) -- a further 60% increase in rice production we will require 300% increase in N fertilizer

Previous Productivity Gains Were Made in Large Part with

Use of CHEMICAL INPUTS

Fertilizers, pesticides, insecticides, fungicides, herbicides, etc. are now

-- giving diminishing returns while -- creating environmental hazards

and health risks,– with rising costs of production and

-- continuing problems of efficacy

How to Reduce Chemical Dependence and Energy

Dependence in Agriculture?• Capitalize maximally/optimally on

biological processes and potentials

• Pay more attention to phenotypes – they are what we eat, not genotypes

• Phenotypes are product of G x E interaction – SRI changes the E

• May be relevant for other crops also

Plant Physical Structure and Light Intensity Distribution

at Heading Stage (Tao et al., CNRRI, 2002)

Dry Matter Accumulation betweenSRI and Control (CK) Practices (kg/ha)at Maturity (Zheng et al., SAAS, 2003)

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Stem Sheath GreenLeaf

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SRICK

Table 2. Different sizes of the leaf blade (cm) with SRI practices (Zheng et al., SAAS, 2003)

Prac-tice

3rd leaf 2nd leaf Flag leaf Average

Length Width Length Width Length Width Length Width

SRI 64.25 1.57 71.32 1.87 57.67 2.17 64.41 1.87

CK 56.07 1.43 62.03 1.57 48.67 2.01 55.56 1.67

+/- 8.18 0.14 9.29 0.30 9.00 0.16 8.86 0.20

%Δ 14.59 9.79 14.97 19.11 18.49 7.96 15.95 11.98

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6-J ul 16-J ul 26-J ul 5-Aug 15-Aug 25-Aug

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SRICK

Figure 1. Change of leaf area index (LAI) during growth cycle (Zheng et al., 2003)

Root Oxygenation Ability with SRI vs. Conventionally-Grown Rice

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

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Much Remains to be Known about the Mechanisms

• Multiple hypotheses can be formulated from the existing scientific literature

• Relatively little soil research has focused on soil biology

• Relatively little plant research has focused on plant roots

• One example is the apparent effect of phytohormones produced by aerobic bacteria and fungi (e.g., auxins, cytokinins)

Cuba – 52 DAP, Variety VN 2084

Greatest Benefit Is Not YIELD• This can vary, often widely; for farmers,

profitability is more important outcome• From society’s perspective, what is most

important is factor productivity – kg of rice per land, labor, capital, and water !

• No question any longer of whether SRI methods give higher yields/productivity but rather how to explain these changes

• SRI can surely be further improved since it has been developed inductively so far

What Are the ‘Negatives’?Surprisingly few -- the main constraint is

labor intensity -- at least initially

• This is receding as a constraint, mostly a problem for first few weeks or seasons– Cambodian evaluation showed no increase

(305 vs. 302 hrs/ha) -- and better timing; in China and India, it is becoming labor saving

– IWMI study showed labor productivity higher by 50-62%, with partial use of SRI methods

– Farmer innovation is helping to reduce labor requirements -- more innovations will come

Roller-marker devised by Lakshmana Reddy, East Godavari,AP, India, to save time in transplanting operations; his yield

in 2003-04 rabi season was 16.2 t/ha paddy (dry weight)

4-row weeder designedby Gopal Swaminathan,

Thanjavur, TN, India

AERATE SOIL at same time weeds are removed/incorporated

Motorizedweeder

developed byS. Ariyaratna

Sri Lanka

Seeder Developed in Cuba

Direct seeding will probably replace transplanting in futureEssential principle is to avoid trauma to the young roots

What Are Other ‘Negatives’?Water control is necessary for best results;

can be obtained through infrastructure or organization – SRI makes this economic

Farmer learning and skill are required -- but this is a benefit, not just a cost

Disadoption has been reported as problem but only in Madagascar (not in Cambodia, India)

Nematodes can be a problem (e.g., Thailand);

need to develop water management strategy

Golden snail – can be controlled (e.g., Philippines)

Chinese Adaptations• Triangular system of planting – Liu

Zhibin, Meishan, Sichuan – got 16 t/ha and award from prov. DOA

• 3-S system – uses 45 d seedlings because of cold temperatures, with single seedlings planted sparsely (10,000 plants/mou), and less water, more organic matter; but no active soil aeration yet -- using herbicides

Normal 3-S

Seedlings are started at the end of winter in plastic greenhouses

Seedling for Seedling for transplanting -- and transplanting -- and

resulting plantresulting plant

Wide Spacing of Plants

Average spacing 15 cm (13-17 cm) by 40 cm Average spacing 15 cm (13-17 cm) by 40 cm

(37-43 cm), 1-2 per hill (37-43 cm), 1-2 per hill

Vegetative Growth VigorouVigorous s

tilleringtillering

Vigorous roots

3-S roots on right

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131131

3-S Field with Variety 131

3-S gives good grain quality

Effects of Different Treatments within 3-S System

Panicles/m2

Grains/ panicle

Seed set (%)

1000-grain wt

(g)

Yield (t/ha)

Change

Control (CK)

540.5 70.1 83.1 24.8 7,808.5 --

3-S METHOD

438.6 106.8 83.0 25.8 10,030.5 + 28.5%

VARIETIES

Dongnong 423

371 136.0 85.0 29.0 12,471.0 +28.6%

Xixuyan 1 375 131.0 90.0 27.3 12,020.5 +24.0%

Dongnong 9914

480 108.0 78.0 25.6 10,351.5 +6.8%

Kongyu 131

450 92.0 90.0 26.0 9,691.5 --

Chinese Results, 2004

• Heilongjiong Province: 10 t/ha in 2004 -- 44,000 ha under 3-S system

• Guizhou Province: high-altitude record set with SRI – 12.9 t/ha

• Zhejiang Province, Tian Tai County: 10.8 t/ha in 2003; 11-12.5 t/ha in 2004 set provincial records for yield– Farmer experimentation is occurring

SRI demonstration fields in Tian Tai, Zhejiang, China

Nie Fuqiu, Bu Tou village, Tian Tai, Zhejiang,describing his experiments within SRI system

CAU evaluation of SRIXinsheng Village, Dongxi Township,

Jianyang County, August 2004

• 2003 – 7 farmers used SRI (SAAS)• 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

Xinsheng Village, Dongxi Township[N = 75] (20% sample of all users)

RICE YIELD (kg/mu) 2002 2003* 2004Standard 403.73 297.88 375.77 Methods

SRI -- 439.87 507.16-----------------------------------------------------------SRI Increase (%) +46.6% +34.8%

* Drought year [Water saving/mu = 43.2%]

Other Results Reported, 2004

Sichuan Province – 60+ trials showed 10.5 t/ha average vs. 7.5 t/ha usual (double usual increase with hybrid rice)SAU – 11.75 t/ha; Leshan – 12.1 t/ha (10

300 mu); Meishan – 13.4 t/ha; SAAS field demonstration (observed) – 11.64 t/ha

Hunan Province – 13.5 t/ha in field demonstration of CNHRRDC (‘SRI’)

Yunnan Province – 18 t/ha CNRRI trial 20.4 t/ha certified by Dept of S&T/SAU

Liu Zhibin, Meishan Inst. of Science & Technology, inraised-bed, no-till SRI field with certified yield of 13.4 t/ha

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, 8/2004

LESS CAN PRODUCE MOREby 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• Greater output is possible with use of fewer or even no external/chemical inputsChanges in management practices give different

phenotypes from rice genomes (cf. Kumar et al., PNAS, 2004)

THANK YOU

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

• Email: tefysaina.tnr@simicro.mg or ciifad@cornell.edu or ntu1@cornell.edu

• In China: zhudf@mail.hz.zj.cn

Proposed/Possible/Probable EXPLANATIONS for

SRI Performance

1st Explanation?Above-Ground Environment

Create ‘the edge effect’ for the whole field• Avoid edge effect only for measurement;

promote it agronomically (triangle spacing)

• Too-close spacing affects photosynthesis within canopy: measurements at AARD (Sukamandi, Indonesia) found that with normal spacing, lower leaves were being ‘subsidized’ by the upper leaves; wider spacing enables whole plant to contribute

2nd Explanation?Nitrogen Provision

• Rice yields increased 40-60% when same amount of N provided equally in both NO3 and NH4 forms vs. when all N is provided as NH4 (Kronzucker et al., 1998)

• BNF increases greatly with alternated aerobic/anaerobic conditions (Magdoff and Bouldin, Plant and Soil, 1970)

• Contributions of protozoa to N supply• Also contributions from endophytes

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

AND NUTRIENT AMENDMENTSResults of replicated 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,with compost

25 1,400 78 10.5

LOAM SOILSRI cultivation,with no amendments

25 75 32 2.1

SRI cultivation,with compost

25 2,000 47 6.6

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 soil

increased 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 they lyse and release P into the soil solution

4th Explanation? 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 by 10-100x, acquiring water, P and other nutrients; they also provide protective/other services to plants

• Flooded rice forgoes these benefits

5th Explanation?Phytohormones

• Aerobic bacteria and fungi produce auxins, 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 is not due just to physiological processes within the plants --stimulated by aerobic microorganisms? Roots are key to SRI

Single Cambodian rice planttransplanted at 10 days

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

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

Root dry weight (g)

Table 13: Root Length Density (cm. cm-3) under SRI, ‘Modern’ (SRA) and Conventional Practice (from Barison, 2002)

Results from replicated on-station trials

TreatmentsSoil layers (cm)

0-5 5-10 10-20 20-30 30-40 40-50

SRI -- with compost 3.65 0.75 0.61 0.33 0.30 0.23

SRI -- without compost 3.33 0.71 0.57 0.32 0.25 0.20

SRA with NPK and urea 3.73 0.99 0.65 0.34 0.18 0.09

SRA without fertilization 3.24 0.85 0.55 0.31 0.15 0.07

Conventional practice 4.11 1.28 1.19 0.36 0.13 0.06

SRI R 2 =

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0.3144

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Rice grain yield response to N uptake

Figure 8: Linear regression relationship between N uptake and grain yield for SRI and conventional methods, using QUEFTS modeling (from Barison, 2002) Results are from on-farm comparisons (N = 108)

N Internal Efficiency

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Figure 9: Estimation of balanced N uptake for given a grain yield for rice plants with the SRI and conventional systems, using QUEFTS modeling (same for P and K) (Barison, 2002)

Results are from on-farm comparisons (N = 108)

Emerging Benefits of SRI?1. Resistance to Abiotic Stresses –

climate becoming more ‘extreme’ and more unpredictable

• Observed resistance to drought (Sri Lanka, several years), hurricane (Sichuan – Sept. 2002), typhoon (AP, India – Dec. 2003), cold spell (AP, India – February 2004)

• Resistance to lodging due to roots?

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

conventional methods (left), SRI (right)

Emerging Benefits of SRI?2. Resistance to Pests and Diseases –

widely reported by farmers – probably reflecting the protective services of soil microorganisms

3. Higher Milling Outturn ~ 15%: SRI paddy raises outturn in India from 66 to 75%; in Cuba, from 60 to 68-71%; adds to paddy yield

• Fewer unfilled grains (less chaff)

• Fewer broken grains (less shattering)

Emerging Benefits of SRI?4. Higher Nutritional Value of Rice?

• SRI can be ‘organic rice’ that is free from agrochemical residues

• Possibly SRI has higher nutritional quality in terms of micronutrients – needs to be evaluated scientifically

• Larger root system gives higher grain weight and greater grain density also greater nutrient density?

Emerging Benefits of SRI?5. Conservation of Rice Biodiversity?

• Highest SRI yields come with HYVs and hybrids (all SRI yields >15 t/ha)

• But traditional/local varieties respond very well to SRI practice, can produce yields of 6-10 t/ha, and even more

• Traditional rices receive higher price

• Higher SRI yields make them popular

• Get an organic premium for export?

SRI STILL RAISES MORE QUESTIONS THAN WE HAVE ANSWERS FOR

• This should please scientists – lot of interesting new work ahead

• We are linking with researchers and practitioners around the world

• Two-pronged strategy: research and practice proceed in tandem -- ‘walking on both legs’ as Mao advised

SRI Experience Could Help to Us to Improve

21st Century 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 energy

sources -- fertilizer, mechanization– Less dependent on agrochemicals -- for

sake of soil & water quality, for health

SRI plant with 87 fertile tillers atCFA Camilo Cienfuegos, Cuba

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. 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

IWMI Data from Sri LankaIWMI Evaluation (Namara, Weligamage, Barker 2003)

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, 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%

PHILIPPINES DATA: AGRICULTURAL TRAININGINSTITUTE, DEPARTMENT OF AGRICULTURE,COTOBATO, SRI Field Day, October 28, 2002

Production Analysis PSB Rc 72H PSB Rc 82 PSB Rc 18Plants/m2 = Hills/m2 16 16 16Panicles/hill 20 25.8 31Grains/panicle 191 155 159Grains/hill 3,825 4,822 4,921Yield/m2 1.16 1.25 1.2Yield (t/ha) 11.6 12.5 12.0

Economic Analysis Pesos/ha Pesos/ha Pesos/haInputs: seeds, org. fertilizer. 3,700 3,320 3,320Other expenses 5,830 5,830 5,830Harvesting, threshing 14,848 16,000 15,360 Cost of Production in P/ha

24,378 25,150 24,510

Income from Production @ 8 P/kg

93,800 100,000 96,000

NET PROFIT P/ha 68,422 74,850 71,490 Rate of Return 280% 298% 292%

SRI CONCEPTS CAN BE EXTENDED TO UPLAND PRODUCTION

Results of trials (N=20) by Philippine NGO, Broader Initiatives for Negros Development,

with Azucena local variety (4,000 m2 area)-- using mulch as main innovation, not young plants

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

ROOT SYSTEM PROMOTION • SRI is becoming referred to in India (AP)

as ‘the root revolution’ -- key factor• Roots benefit from wider plant spacing,

aerated soil, more soil organic matter --from both compost and root exudation

• Roots are supported by more abundant and diversified populations of soil biota -- bacteria and viruses produce PGRs

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

Root Research Reported by Dr. Ana Primavesi (1980)

Shoot and root growth of maize (in g) 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 when 43 56 changed every other day

Contribution of SOIL MICROBIAL PROCESSESMicrobial activity is known to be

crucial factor in 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 otherwise unavailable to plant roots

• Improve soil structure and health -- water retention, soil aggregation, aeration, pathogen control, etc.

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 6.39Note: All of these averages are for 6 replicated trials

Effects of SRI vs. Conventional PracticesComparing Varietal and Soil Differences

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Spread of SRI in Asia National Natl. Network Summary of SRI Results to Date

Workshops & CoordinationBangladesh 9/02, 12/03 BRAC 30-50% average increase,

up to 12 t/haCambodia 1/03 CEDAC Doubling from 2 to 4+ t/ha;

from 28 to 10,000 in 3 yearsChina 3/03 CNRRI 12-13 t/ha with hybrids;

up to 16 t/ha (Sichuan)India 8.5-12.2 t/ha results in AP vs.

4.3-6.3 t/ha; even 15.7 vs. 7.5Indonesia 7/02 AARD ADRA results 8.0-11.7 t/ha,

IPM program ave. 9.25 t/haLaos 4/02 IRRI/Laos Mixed results; up to 6-7 t/haMyanmar 5.5 t/ha > 2x average yieldsNepal 6/03 NGOs/

CIMMYTInitially mixed results; now8 t/ha average achieved by FFS

Philippines 4/02, 3/03 PhilippineGreens

Widely varying results;ATI/DOA got 12 t/ha

Sri Lanka 12/03 7-8 t/ha ave. yields; up to 13 t/hawith traditional varieties

Thailand 6/03 NGOs 30-60% increases reportedInterest: Japan, Malaysia, Pakistan, South Korea, Taiwan

Spread of SRI in Africa• Madagascar: now 50,000-100,000 farmers,

average about 6-8 t/ha, some double or more• Sierra Leone: 2.5 5.3 t/ha for 160 farmers• The Gambia: 2.5 7.4 t/ha for 10 farmers• Benin: 1.6 7.5 t/ha in controlled trial• Guinea: 2.5 9.4 t/ha (hybrid + SRI)• Mozambique: good soils 3 saline soils 3-8 t/ha• Senegal: 4-5 9-11 t/ha (FAO trials)• Interest in, but no results yet from: Ethiopia, Ghana,

Mali, South Africa, Tanzania, and Uganda

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 of 6 t/ha (not profitable given costs of production)

• Interest in, but no results yet from: Barbados, Brazil, Colombia, Dominican Republic, Guyana, Haiti, and Venezuela