Developing ISFM Options for Smallholder

Agriculture in Africa: Experiences from WA

Sylvester OIKEH (Ph D)

Africa Rice Center (WARDA)

Cotonou, Benin

Seminar for the Position of IITA Soil Fertility Specialist

22 September 2008, IITA, Ibadan, Nigeria

• Background

• Historical perspectives on soil fertility

• Key soil fertility research at IITA

• Concept of ISFM

• My vision

Outline of Presentation

• Linking vision with key experiences

• Resource mobilization efforts

• Conclusion

Outline of Presentation Cont‟d

Background

What is Soil Fertility?

• Capacity of the soil to supply nutrients (N, P, K and other essential nutrients) to the crop

• Mixture of soil chemical, physical and biological factors affecting land potential

• Major problem: Inherent low fertility of African soils

Macronutrient Application Vs. Losses in Africa

4.4

0.5

3.0

0.8

0.3 0.2

0.0

0.5

1.0

1.5

2.02.5

3.0

3.5

4.0

4.5

5.0

N P KNutrients

Millio

n t

on

s p

er

ye

ar Loss

Applied

• In the developed world, overuse of fertilizer & manure is damaging envt.

• In SSA, low use of fertilizer is a major cause of environmental degradation

and poverty.

• Africa losses USD 4 billion/yr due to soil nutrient mining.

Source: Sanchez et al. 1997)

SOIL NUTRIENT MINING IS KILLING AFRICA

1995-97 2002-04

Source: IFDC

NetherlandsVietnam

JapanUK

ChinaFrance

BrazilUSAIndia

South AfricaCubaBenin

MalawiEthiopia

MaliBurkina Faso

NigeriaTanzania

Mozambique GuineaGhana

UgandaKg/ha

Source: FAOSTAT, July 2003;

Norman Borlaug, 2004

0 100 200 300 400

Fertilizer use: 8 kg per ha

in Sub-Sahara Africa is the

lowest in the world

500 600

• Fertilizer Summit, 2006: „to increase the fertilizer use from 8 to 50 kg ha-1 nutrients by 2015‟.

• Fertilizer is a “golden bullet” to power African Green Revolution (Adesina, 2007)

Fertilizer Use Around the Globe

Historical Perspectives in

Addressing Soil Fertility ProblemsPeriod Paradigm Role of fertilizer Role of organic

inputs

Experiences

1960s

&

1970s

External

input

Paradigm

Use of fertilizer

alone will ↑ and

sustain yields

Organic resources

played a minor role

Limited success

because of Shortfall

in infrastructure,

policy, etc.

1980s Organic

input

Paradigm

Fertilizer played a

minimal role

Organic resources

are main source of

nutrients (Alley

farming system)

Limited adoption; OM

production requires

excessive land &

labor

1990s Sanchez’

2nd

Paradigm

Fertilizer use was

essential to

eliminate the main

nutrient

constraints

Organic resources

were the entry

point; but served

functions beside

nutrients release

Difficulties to access

organic resources

hampered adoption

(e.g. improved fallow)

2000s ISFM

Paradigm

Fertilizer is a

major entry point

to ↑ yields and

supply needed

org. inputs

Access to organic

resources has both

social and

economic

dimensions

On-going!

(Here we are!)

Annon (2007)

• Diagnostic studies on identification deficient nutrients in production systems across agroecologies

• Fertilizer response studies, but mostly on cereals (maize); limited on roots and tubers

• Alley farming/ improved fallow (limited adoption)

• Cereal-legume rotations (include ISFM)

• Use of phosphate rock in legume rotation systems (limited promotion)

Key Soil Fertility Research at IITA

Concept of ISFM

The application of soil fertility management practices (appropriate fertilizer + organic input + improved germplasm) and the knowledge to adapt these to local conditions to optimize fertilizer and organic resource- use efficiency and crop productivity

ISFM + Enabling environment

Integrated Soil Fertility Management Strategy

Integrated Pest

management

Institutions

and policy Soil Conservation

water management

Resilient germplasm /

fertilizer (Org+Inorg)

Markets

Ecosystem

Services

ISFM

• Promote ISFM in cereal-legume rotations with focus on promiscuous soybean-maize systems in Africa using participatory approaches

• Integrating mineral fertilizer component of ISFM package based on site-specific fertilizer balanced management practices

Vision

• Integrate ISFM principles into conservation agriculture in SSA with linkage to climate change/ land degradation

• Transform IITA Nutrition lab to a center of excellence for Bio-fortification studies

Vision cont‟d

• Review and establish ISFM guidelines for roots and tubers (particular focus on yam & cassava)

Vision cont‟d

Key issues:

• Limited N-use efficient crop varieties

• Dynamic nature of N in farmers‟ fields

• Limited use of available ISFM options

Promote ISFM in cereal-legume rotations using participatory approach

Experiences: N-use efficient crop varieties

(Screened maize cultivars under variable N to identify N-efficient cultivar)

Promote ISFM in cereal-legume rotations using participatory approach

0 0.1 0.2 0.3 0.4 0.5

75-90

60-75

45-60

30-45

15-30

0-15

So

il d

ep

th (

cm

)

0 g/plant

2.26 g/plant

1994/35 DAS

a

0 1 2 3 4 5 6

75-90

60-75

45-60

30-45

15-30

0-15

So

il d

ep

th (

cm

)

Root length density (cm cm-3

)

0 g/plant

0.56 g/plant

2.26 g/plant

1994/silking

N Vs. Root Length DensitySource: Oikeh, Kling, Horst, & Chude (1999). Field Crop Res. 62: 1-13

• N application stimulated root

production in surface soil at

early growth stage

• Greater root growth and

distribution observed at 30 kg N

ha-1 (0.56 g/plant) than at 0N or

120N

Root Length Density of Maize varieties

0 0.1 0.2 0.3 0.4 0.5

75-90

60-75

45-60

30-45

15-30

0-15

So

il d

ep

th (

cm

)

35 DAS

Cultivar

Plant ht

(cm)

(25 DAP)

RLE

(mm/day)

25-28 DAP

DM

(g/plant)

35DAP

EV8728 61.5 74.5 17.8

87TZPB 57.5 69.8 15.2

SPL 63.5 79.6 18.0

8644-27 (HYB)

61.3 73.9 15.2

TZB

(CTL)

59.5 70.8 14.3

LSD

(p=0.1)

1.6 3.1 2.4

0 1 2 3 4 5 6

75-90

60-75

45-60

30-45

15-30

0-15

So

il d

ep

th (

cm

)

Root length density (cm cm-3)

TZB

8644

SPL

TZPB

EV8728

Silking

Source: Oikeh, Kling, Horst, & Chude (1999). Field

Crop Research. 62: 1-13

• Varietal differences in RL at 35DAS

• All improved cvs. had better RL and

growth than the check

• TZPB & SPL had better root systems

in lower depth at silking

Cultivar

ASI

(d)

LGF

(d)

Grain yield

(Mg ha-1)

HI

(%)

N-util. eff.

(%)

N-use eff.

(kg grain/kg avail. N)

EV8728 3.4 48.0 5.0 40 50 18.5

87TZPB 5.3 45.6 4.8 36 46 16.6

SPL 3.1 43.4 5.0 41 50 17.4

8644-27 5.2 47.9 5.2 43 54 18.5

TZB-SR 4.2 46.1 4.7 35 45 16.6

SED 0.2* 0.5** 0.1+ 0.5** 0.7** 0.5*

CV (%) 3 3 16 9 9 20

Phenology, grain yield, HI, and N efficiency

parameters of maize cultivars as influenced by N

Source: Oikeh and Horst 2001: In: W.J Horst et al. (eds.). Plant Nutrition: Food security and sustainability of agroecosystems.

Development in Plant and Soil Science Book Series. Kluwer Academic Publishers, The Netherlands.

Mean N uptake over time as

influenced by N

Source: Oikeh, Carsky, Kling, Chude, & Horst (2003). Agriculture Ecosystems and Environment 100: 181-191.

Cultivar

N

(kg ha-1)

N uptake (kg ha-1)

35 DAP Midsilk Grain Stover NHI (%) Total N

0 11 42 29 18 60 47

30 18 54 47 25 65 72

120 19 86 87 39 69 126

SED 1* 3** 2** 1** 1** 3**

EV8728 17 59 57 26 68 82

87TZPB 15 70 56 29 65 85

SPL 19 55 59 27 68 86

8644-27 15 63 53 26 66 79

TZB-SR 14 56 48 29 58 77

SED 1* 4* 3* 1 ns 1** 3ns

Experiences: Dynamic nature of N in farmers„ fields

Livelihood analysis:

5 Villages in 3 States, NGS, Nigeria

Major constraints as ranked by farmers:

• Low soil fertility/lack of fertilizers

• Striga hermonthica infestation

• Early season drought causing replanting

Promote ISFM in cereal-legume rotations using participatory approach

Patterns of NO3-N (0-30 cm) Dynamics in 35 Farmers‟ Fields, NGS

Source: Weber, Chude, Pleysier, & Oikeh (1995). Exp. Agric. 31: 333-344.

(7 fields)

(7 fields)

(7 fields)

(14 fields)

Managing N Dynamics Using ISFM Package

ISFM with Stylo organic inputs (fallen leaves + roots) slowed down N mineralization and N losses in soil-plant system

Source: Oikeh, Chude, Carsky, Weber, & Horst (1998). Experimental Agriculture 34: 73-83

So

yb

ean

Sty

lo

Maiz

e0

1

2

3

4

5

6

8644-27 (N-use eff.)

TZB-SR (N-ineff.)

Previous crop

Gra

in y

ield

(t

ha

-1)

On-farm ISFM Package

So

yb

ean

Sty

lo

Maiz

e0

1

2

3

4

5

6

8644-27 (N-use eff.)

TZB-SR (N-ineff.)

Previous crop

Gra

in y

ield

(t

ha

-1)

1.3 Mg ha-1 yield advantage

from legume rotation with

N-use eff. maize over 2-yr

continuous N-ineff. maize

Source: Oikeh, Chude, Carsky, Weber, & Horst (1998). Experimental Agriculture 34: 73-83

Mean Mineral N Balance (loss)

from Soil-plant System

TZ

B-S

R

87T

ZP

B-S

R

EV

8728-S

R

SP

L

8644-2

70

20

40

60

80

100

120

140

160

Cultivars

N lo

ss

(kg

ha

-1)

• 35 – 122 kg N ha-1

lost (leaching)

• SPL had > capacity to take up N during grainfilling period thus minimizing N losses

• SPL had deep fine root system

Source: Oikeh, Carsky, Kling, Chude, & Horst (2003).

Agriculture Ecosystems and Environment 100: 181-191.Nl/g = (Nup(t2) + Nmin(t2)) (Nfert + Nmin(t1) + N(rain))

Model Maize (Ideotype)

for African Savanna (e.g. SPL)

Adapted: Oikeh, Kling, Horst, & Chude (1999). Field Crop Res. 62: 1-13

• High seedling vigor and dense root system in

surface soil at early growth stage

• Fine, deep, and dense root system late in

season with extended N absorption into

grainfilling

• Short ASI and LGF

• > one ear per plant under low N

• High grain yield and harvest index

• Good grain processing quality (Oikeh, Kling, & Okoruwa

(1998). N fertilizer management effects on maize grain quality in West Africa. Crop

Science 38:1056-1061)

What Next ?

• Promote grain legume-cereal ISFM Africa-wide using participatory approaches

• Develop new ideotypes of crops for Africa using experience from maize ideotype

• Use existing models to predict nutrient flow and out-scaling ISFM options

Key issues:

• Limited fertilizer recommendations based on site-specific variability in soil fertility

• Fertilizer applications based on crop responses/ agroecologies lead to over or under-application in some fields

Integrating mineral fertilizer component of ISFM options based on site-specific FBMP

Experiences: Cultivar response to fertilizer (cultivar fertilizer) across agroecologies

Integrating mineral fertilizer component of ISFM options based on site-specific FBMP

N Vs. Dry-matter Yield

Dry-matter Yield

0 30 60 90 1200

2

4

6

8

10

12

14

16

Y =8.8 + 6.0N - 1.3N2 R2=1.0

Y =2.8 + 3.5N - 0.8N2 R2=0.99

Total

Grain

Nitrogen rate

(kg ha-1)

Yie

ld (

t h

a-1

)

Source: Oikeh, Kling, Horst, & Chude (1997). Proceedings 5th Eastern and Southern Africa Regional Maize Conf.,

Arusha, Tanzania 3-7 June 1996. CIMMYT, Addis Ababa, Ethiopia, pp 163-167

• 5 maize cultivars

screened under 4 N

levels for 2 yrs

• 60 kg N ha-1

adequate for maize

production under the

conditions of the

experimental site

NPK vs. Mean Grain Yield of 4

NERICAs Humid Forest, Nigeria

0

1

2

3

4

5

6

Fertilizer treatment

NE

RIC

A y

ield

(M

g h

a-1

)

a

b

c

N60-P13-K25= 60 kg N, 13 kg P and 25 kg K per ha

N120-P26-K25= 120 kg N, 26 kg P and 25 kg K per ha.

N60-P13-K25 N120-P26-K25

Source: Oikeh et al. (2006). Fertilizer summit, 2006

60 kg/ha N

13 kg/ha P

25 kg/ha K

Zero N60-P13-K25 N120-P26-

K25

What Next ?

Integrate mineral fertilizer component of ISFM options based on site-specific nutrient content and crop requirement

Key issues:

• Climate change

• Land degradation

• Declining soil fertility

Integrate ISFM principles into conservation agriculture in SSA with linkage to climate change/ land degradation

Experience: Cowpea-NERICA Ecotechnology

(example of ISFM option developed with farmers in NGS, Benin)

Integrate ISFM principles into conservation agriculture in SSA with linkage to climate change/ land degradation

85-day NERICA 8

(Resilient, N-use efficient)

75-day Dual-purpose CowpeaFarmer‟s 80-day Cowpea (Katchè)

Organic inputs

+

Mineral N (20 kg ha-1)

Opening Ceremony of Soil Fertility Lab, WARDA Cotonou

AAS

Cowpea Rotation Vs. Soil-N at

21 and 42 DAS in 5 farmers‟ Fields

Rotation

NO3-N (T21; kg ha-1) Nmin (T42; kg ha-1)

Soil Depth (cm) Soil Depth (cm)

0 – 15 15 – 30 0 – 15 15 – 30

IT89KD-288 11.0 12.8 31.0 26.2

IT90-277-2 17.7 8.6 33.1 22.7

IT97-568-11 20.6 15.1 40.5 25.7

IT97K-1069-6 11.6 14.3 36.4 28.2

IT93K-452-1 15.6 13.9 28.0 23.5

Katechè (local) 12.7 8.5 25.0 27.0

Fallow 12.6 10.4 24.9 22.7

SE (Rot Depth) 2.78 3.31

Source: Oikeh, Niang, Abaidoo, Houngnandan, Koichi, Kone, & Toure (??). Cowpea-NERICA Rice Ecotechnology for

Sustainable Management of Degraded Tropical Savanna Soil. Soil Science Society of America Journal (in preparation).

0

0.2

0.4

0.6

0.8

1

1.2

IT90-277-2 IT97-568-11 IT97K-1089-6 IT93K-452-1 Local (Katché) Fallow

Previous crops

Gra

in Y

ield

(M

g.h

a-1

)

Mean NERICA8 Yield Vs. Previous Cowpea

(5 farmers‟ fields, NGS, Benin)

• Previous cowpea (IT97-568-11) + 20N gave 2.4 times > yield than

previous fallow + 0N (CTL) in Cowpea-NERICA Ecotechnology

Source: Oikeh, Niang, Abaidoo, Houngnandan, Toure & Mariko (2008). Abstract Submitted to Annual Meeting of CSA Societies, USA

N Fertilizer Replacement Value of Previous Cowpea cv. IT97-568-11

0

0.5

1

1.5

2

2.5

0 10 20 30 40 50 60 70 80

N Level (kg ha-1)

Gra

in Y

ield

(M

g h

a-1)

26 kg/ha N replacement

(N savings to the farmer)

from NERICA8 Vs. N

response curve

Source: Oikeh, Niang, Abaidoo, Houngnandan, Toure & Mariko (2008). Abstract Submitted to Annual Meeting of CSA Societies, USA

What Next ?

Promote conservation agriculture using ISFM principles

Key issues:

• Analyses of samples in advanced lab

• High transaction costs in developing micronutrients enhanced crops

Transform IITA Nutrition lab to center of excellence for Bio-fortification studies

Experience:

“Micronutrient Enhancement of Maize to Reduce Hidden Hunger”

Transform IITA Nutrition lab to center of excellence for Bio-fortification studies

Calcium

Deficiency

Ricket, WHOIron Deficiency Anemia, WHO

Summary of Findings

• Evaluated 49 late- & early-maturing maize across 3 contrasting ecologies for 2 yrs for Fe & Zn conc.

• Mean Fe: 16.5 – 23.1 mg kg-1 Late maize

• Mean Zn: 16.1 – 23.9 mg kg-1 “

• Mean Fe: 16.9 – 20.7 mg kg-1 Early maize

• Mean Zn: 18.2 – 21.2 mg kg-1 “

• Evaluated bioavailable Fe using a ModelGut (mimic digestive system; Glahn et al. 1996)

Sources: 1. Oikeh, Menkir, & Maziya-Dixon (2003). Journal of Plant Nutrition. 26: 2307 – 2319.

2. Oikeh, Menkir, Maziya-Dixon, Welch, Glahn, & Gauch JR. (2004). Journal of Agric. Science (Camb.). 142: 543 – 551.

A Cartoon of the In Vitro Digestion/Caco-2 Cell Culture Model

(Glahn et al. 1996)

500 mg maize sample

Pepsin Digestion

pH 2, 1 h, 37 C (50 mL tube)

Pancreatin-Bile Digestion

pH 6.8 – 7.0, 2 h, 37 C

Soluble iron

Insert ring

Dialysis membrane

15K MWCO

Culture well

Caco-2 cells

Harvest cells for ferritin determination

24 h post start of Panc/Bile digestion

Source

Pr>F

% of total variation

Fe bioav.(%)

Fe

bioav.

LOG (%)Fe bioav.

Loc 0.444 0.523 <1

Var 0.006 0.029 12

V x L 0.586 0.353 10

CV (%)

35 7

ANOVA of location, variety and G E interactions

on Fe bioavailability from Early-maturing maize

Sources: Oikeh, Menkir, Maziya-Dixon, Welch, & Glahn (2003). Journal of Agricultural and Food Chemistry 51: 3688-3694

Caco-2 Cell Ferritin Formation

Early-Maize (as % of Control)

3 4 2 6 51

1 81

4 11

5 91

91

31

82

0 71

61

01

71

20

25

50

75

100

125

150

175

Control(22)

* * * *

Variety

Caco

-2 C

ell

Ferr

itin

(as %

of

Co

ntr

ol)

Sources: Oikeh, Menkir, Maziya-Dixon, Welch, & Glahn (2003). Journal of Agricultural and Food Chemistry 51: 3688-3694

What Next ?

Back-stop breeders to develop and promote micronutrient enhanced crops at IITA

Review and establish ISFM guidelines for roots and tubers

Key issue:

Limited studies on improving soil

fertility for roots and tubers in Africa

Experience: None!

Review and establish ISFM guidelines for roots and tubers

What next?

Literature review on soil fertility studies

on roots and tubers

Conduct ISFM studies on roots and tubers

Develop ISFM guidelines for roots and

tubers production in Africa

Resource Mobilization Efforts (2006-2008)

Project Donor Value Partner

Smallholder rice-based livelihood and

income enhancement project for Liberia

UNDP $ 5.0m Min. of Agric.

Liberia/WARD

A/IITA/ AVRDC

Alleviating rural poverty through

improving rice production in E. & S.

Africa

IFAD $ 1.5m IRRI/WARDA

Enhancing smallholder access to

NERICA seed for alleviating rural

poverty in WCA

IFAD $ 1.5m WARDA

Development of sustainable rice

farming systems in LAC soils in West

African lowlands: Nutrients cycling in

sawah vs. non-sawah rice farming

systems

MOP

Japan

$ 0.18m WARDA

NUE Rice for Africa USAID $4.0m AATF/ARCAR

DIA/ WARDA

The vision of African Leaders: “to increase the fertilizer use from 8 to 50 kg ha-1 nutrients by 2015” (Fertilizer Summit, 2006) can only be actualized with the right enabling environments, with the right people in the right places

Conclusion

Thank you!

Merci!!

Asante sana!!!

Eshe‟o!!!!