sustainable intensification of maize-bean production among smallholder farmers in western kenya....

Sustainable intensification of maize-bean production among smallholder

farmers in western Kenya

Achieng, J.1, F. Kanampiu2, Y. Chauhan3, D. Rodriquez4

1Kenya Agricultural Research Institute2CIMMYT, Nairobi, Kenya

3Agri-Sciences Queensland, Toowoomba, Australia4The University of Queensland, Toowoomba, Australia

15th World Congress on Conservation Agriculture, Brisbane

Introduction & Background

• Maize is a major staple food in Kenya

• Often grown in association with beans

• About 80% of maize produced by smallholders

• Current yield: ‹1.0 t ha-1 against potential

of ≥ 3.5 t


Justification

• Conv. tillage practices have degraded the soils• Droughts and long dry-spells are regular• Use of inorganic fertilizers is not common• Demand for maize increases by 4% annually;

Food security is threatened• Need to embrace Conservation Agriculture to

restore lost soil fertility


Objectives

Long-term:• To test resilient smallholder maize-bean farming

technologies based on CA principles

Short-term:• To investigate the effects of minimal tillage and

residue retention on water use efficiency, SOM and maize-bean yield

• To test the capacity of APSIM to model performance of maize-beans system under CA practices


Expected Output

• About 30% increase in yield due to adoption of CA practices within a period of about 10 years

• About 30% decrease in production risks due to adoption of CA practices within a period of about 10 years


Materials & Methods

• Sites: 5 – two in Siaya: low potential zone– two in Bungoma: medium potential zone– One on-station: medium potential zone

• Participating farmers: 130; members of farmers’ groups

• Type of research: Participatory and farmer-managed 65th World Congress on Conservation Agriculture, Brisbane

Materials & Methods Cont

Treatments1. Conventional practice

2. CA + non-inoculated beans

3. CA + inoculated beans

4. CA + desmodium

Varieties: Depended on site and season

Fertilizer: CA treatments = 80 kg N and 60 kg P/ha

Conventional = 40 kg N and 30 kg P/ha

Plot Size: 20m X 17m75th World Congress on Conservation Agriculture, Brisbane

Materials & Methods Cont

Weather data

• Daily rainfall• Daily Min & Max temp• Daily Min & Max temp for 30 yrs• Daily Radiation for 15 yrs

A farmer showing group members how to record weather data and rainfall trend that month


Materials & Methods Cont.

• Soil DataSoil sampled from 4 layers (up to 90cm), 3 times a season for:• Gravimetric water determination• Bulk Density determination• Chemical analysis



5th World Congress on Conservation Agriculture, Brisbane 10

Scientist and technicians examining degraded Western Kenya soils

Tumaini Farmers’ Field School members discussing pros and cons of CA


• Crop Data–Maize crop sampled 3 times each season

for chemical analysis–Maize & bean yield and related parameters


Materials & Methods Cont.Maize and beans grown under conventional practice, western Kenya

Maize and beans grown under CA practice, western Kenya


Materials & Methods Cont.Residue retained in a maize crop in CA trial, western Kenya

Desmodium grown as a cover crop in maize in CA trial, western Kenya


Technology DisseminationThe District Commissioner being shown CA plots at Siaya Field Day Provincial Administration staff attended the field

day. DCs and Chiefs are influential and respected


Result : Water Use EfficiencyTreatment WUE

(kg/mm/ha)2010 LR Season

WUE (kg/mm/ha)

2011 LR Season

Conventional 8.5 8.0

CA + non-inoculated beans 10.8 11.9

CA + inoculated beans 9.5 9.9

CA + desmodium 9.8 9.9

Conventional practice gave lower WUE compared to CA

CA practices progressively increased WUE while conventional practice progressively reduced the WUE


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Result: Crop Yield (2010 Season)

Treatment Beans (kg/ha)

Maize (kg/ha)

Conventional 355c 4,075

CA + non-inoculated beans 626b 4,650

CA + inoculated beans 927a 4,416

CA + desmodium 707ab 4,483

Mean 654 4,406

LSD (5%) 231 ns

Rhizobial inoculation increased bean yieldCA had no effect on maize yield

5th World Congress on Conservation Agriculture, Brisbane16

Result 2011 Season: Crop Yield

Treatment Beans (kg/ha)

Maize (kg/ha)

Conventional 640a 2,810b

CA + non-inoculated beans 520ab 5,150a

CA + inoculated beans 390ab 4,330a

CA + desmodium 320bc 4,310a

Mean 468 4,150

LSD (5%) 240 989

Conventional practice gave highest bean yieldCA practices gave higher maize yield compared to conventional practice

5th World Congress on Conservation Agriculture, Brisbane17

Suitability of APSIM

The slope of the regression between observed and predicted yield is R2 = 0.9, indicating a high degree of accuracy


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0

1500

3000

4500

6000

0 1500 3000 4500 6000

Observed yield (kg/ha)

Pre

dict

ed y

ield

(kg

/ha)

Beans

Maize

1:1 line

R2=0.9

ConclusionsCombination of minimal tillage and residue retention:– maximized soil water use and hence can be an

effective tool in mitigating effects of drought and prolonged dry spells

– More than doubled maize yield; food security among smallholders can be achieved in a short-run

APSIM can model performance of maize-beans system under CA practices

Farmers beginning to appreciate CA 5th World Congress on Conservation Agriculture, Brisbane

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Challenges

oCompetition for crop residues

oLack of appropriate implements to be used under very smallholder farms

oAnts that feed on residue


AcknowledgmentsoKARI: For facilitating the researchoCIMMYT: For technical backstoppingoACIAR: For financial supportoWestern Kenya farmers: For implementationoWCCA Organizing Committee: For

accepting the paperoThis esteemed audience for accepting to

listen to the presentation


sustainable intensification of maize-bean production among smallholder farmers in western kenya....

Education

bean yield

food security

ca practices

ca trial

conservation agriculture

model performance

minimal tillage

materials