Intensif afr

Conference Abstracts

Challenges and Opportunities for
Agricultural Intensification of the
Humid Highland Systems of sub-
Saharan Africa

Fertility

Soil
Biology

banana
2008

Challenges and Opportunities for Agricultural Intensification of the Humid Highland Systems of sub-Saharan Africa

2


Contents

INTRODUCTORY KEYNOTES 5

THEMATIC ORAL SESSIONS 9

THEME 1: SYSTEM COMPONENTS 11


THEME 3: DRIVERS FOR ADOPTION 31

THEME 4: COMMUNICATING COMPLEX KNOWLEDGE 41

POSTER SESSIONS 51


THEME 2: SYSTEM INTEGRATION 205

THEME 3: DRIVERS FOR ADOPTION 239

THEME 4: COMMUNICATING COMPLEX KNOWLEDGE 277

AUTHOR INDEX 293

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4


INTRODUCTORY
KEYNOTES

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6


1. Sustainable intensification and the food security challenge
Brian Keating1 and Peter Carberry1

Commonwealth Scientific and Industrial Research Organisation (CSIRO),
1

Canberra, Australia.

Abstract

Global food demand is estimated to increase between 50 and 80 percent between
2010 and 2050 – with the range driven by variation in the key drivers such as
population growth, per capita consumption trends, diversion to biofuels and food
wastage rates. Pathways by which this challenge can be met include; reducing
the demand trajectory, filling the production gap and avoiding losses of current
productive capacity. This paper focuses on the opportunity to expand food supply
to fill this projected increase in demand. Challenges of this scale have been met
in the past – between 1961 and 2008, agricultural output increased by 179 percent
globally. In many parts of the world, these production increases were achieved
by intensification of agricultural practices, in particular via combining inorganic
fertiliser and agri-chemical inputs with intensive tillage and improved varieties. The
longer term sustainability of such intensive systems remains a concern, but there
is little doubt that without the higher yields now being achieved in much of the
developing world, the numbers of undernourished would be much higher than the
current (still unacceptable) levels. While yields were rising in response to agricultural
intensification in other parts of the world, sub Saharan Africa maintained (just) food
production per capita by expanding the land footprint and productivity levels per
unit land remain low. While there is still scope for further expansion of agricultural
land, particularly in sub Saharan Africa and in parts of South America, the clearing
of forests and woodlands and cultivation of grasslands is going to generate a
significant load of greenhouse gases on an already overloaded atmosphere – with
consequences for climate change and potential for negative feedback on agricultural
productivity. Given the food demand pressures and the environmental constraints
(carbon, water, biodiversity), there seems little alternative to an intensification
pathway for agriculture – but it needs to be a sustainable one (i.e. eco-efficient) in
terms of nutrient and water cycles and agro-ecological functions. This conclusion
applies generally, but the potential upside is greatest in Africa where inputs are
very low and productivity is coming off a low baseline. In this paper we argue for a
strong evidence base to help guide interventions towards sustainable intensification.
We present a diagnostic framework applicable at the field and farm scale, but also
argue that progress in productivity growth will be slow without concerted efforts
to embed agricultural R&D in a wider innovation effort. Such an effort needs to
support the evolution of a system of enabling institutions (input and output markets,
public policy settings, private sector activity, trade and regulation) that are a pre
condition for any transformation in the African farm sector.

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2. Paradigm Change for African Agriculture: why and how to make
the transition
Hans R Herren

Millennium Institute, Washington DC, USA

Abstract

Agriculture needs to transition from being a major problem for climate change, to the
solution, while at the same time it also needs to become the true engine of sustainable
development. The International Assessment of Agricultural Knowledge, Science and
Technology for Development (IAASTD) is a unique and comprehensive assessment of
Agricultural Knowledge, Science and Technology, which outlined the path for such a
transition. It started with requests from the private sector and NGOs to the World Bank,
to look at new ways for agriculture and food systems to assure sufficient and quality
food, fiber and feed production for the long term under the challenges of increased and
changing demand, shrinking natural resources and climate change, while also dealing
with the more immediate perennial hunger and poverty nexus. The IAASTD was
launched by the major UN agencies at the Johannesburg World Summit on Sustainable
Development in 2002, and subsequently officially endorsed by the OECD and other
countries at a Plenary meeting in Nairobi in 2004. A Bureau made up of representatives
from government, multilateral agencies and civil society groups, including the private
sector, guided all the steps of the assessment and endorsed over 400 authors, from
developed and developing nations covering agricultural and related disciplines. In
a first step, some 800 stakeholders framed the key questions to be addressed by the
report’s authors at workshops held in the five regions covered by the assessment (North
America and Europe, Latin America and the Caribbean, Sub-Saharan Africa, Central
and West Asia and North Africa and South Asia and the Pacific). Of main interest
was how the AKSTs of the past 50 years influenced where we are today in terms of
agricultural production and food systems and how to reshape these for reducing hunger
and poverty; improving rural livelihoods; improving nutrition and human health;
and facilitating environmentally, socially, equitable and economically sustainable
development. In the report series “Agriculture at a Crossroads”, the IAASTD authors
emphasized the need for a new paradigm in AKST that will lead to food systems,
that are in harmony with the environment, i.e., agroecology, organic agriculture, that
mitigates rather than contribute to climate change, that has reduced external energy
inputs in terms of synthetic fertilizers and pesticides, that is high in genetic and system
diversity, that targets the small and family farms and one that assures food security and
sovereignty at national level. It also emphasized the multi-functionality of agriculture,
and in particular its social, environmental and economic aspects, which are all linked
and key in moving to a socially, environmentally and economically sustainable and
productive agriculture in the medium and long term. It suggest among others that
ecosystem services be remunerated for all farmers instead of providing market distorting
production and export support to the industrialized country farmers. The feasibility
of a green agriculture to meet the sustainability and millennium development goals
is presented, based on modeling results from the Millennium Institute, utilizing the
options for action from the IAASTD report.

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THEMATIC ORAL
SESSIONS

9


10


THEME 1: SYSTEM
COMPONENTS

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12


3. Below- and aboveground organic inputs and the sustainability
of agriculture: productivity and supply of ecosystem services
Meine van Noordwijk1, Kurniatun Hairiah2, Bernard Vanlauwe3, Sileshi
Weldesemayat4, Edmundo Barrios5, Bob Boddey6 and Georg Cadisch7

1
Ecosystem Services for Poverty Alleviation (ESPA), Scotland, UK; 2Faculty of
Agriculture, University of Brawijaya, Indonesia; 3Tropical Soil and Biology Institute
of the International Center for Tropical Agriculture (CIAT-TSBF), Nairobi, Kenya;
4
World Agroforestry Centre (ICRAF), Nairobi, Kenya; 5Centre for International
Development, Harvard University, Cambridge, USA; 6Embrapa-Agrobiologia, Rio
de Janeiro, Brazil; 7University of Hohenheim, Stuttgart, Germany

Abstract

Organic inputs to the soil can derive within the field from aboveground plant
residue left at harvest time, from belowground inputs (roots, rhizosphere foodwebs
and mycorrhizal hyphae) and externally, from recycled waste products (including
manure and compost). Organic inputs serve functions at the surface, including
protection of the soil from erosion, reduction of soil evaporation and regulation of
topsoil microclimate, as well as after incorporation to the soil, including maintenance
of soil structure, buffering of nutrients and supply of nutrients by mineralization.
The tradeoff between these above and belowground functions is modulated by
soil tillage and presence of soil fauna. We review the literature on a number of
hypotheses: I. In the absence of soil tillage or active worm fauna, aboveground litter
contributes little to soil organic matter, most of which derives from root turnover,
II. Nutrients mineralized from aboveground litter decomposition are available to
plants , as superficial roots develop where surface litter is (semi)permanent and/
or nutrients leach into the root zone. III. In the presence of permanent surface litter,
the dependence of soil function on soil organic matter for soil physical properties is
reduced as well as the rate of soil organic matter decomposition, IV. ’Low-quality’
litter, with e.g. high polyphenol contents, is to be preferred over material with higher
rates of decomposition where agricultural sustainability on slopes is an issue.

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4. CIALCA interventions for productivity increase of cropping
system components in the African Great Lakes zone.
P. Pypers1, W. Bimponda2, E. Birachi3, K. Bishikwabo4, G. Blomme5, S. Carpentier6, A.
Gahigi7, S. Gaidashova7, J. Jefwa1, S. Kantengwa4, J.P. Kanyaruguru8, P. Lepoint9, J.P.
Lodi-Lama4, M. Manzekele2, S. Mapatano10, R. Merckx6, T. Ndabamenye7, T. Ngoga7, J.J.
Nitumfuidi2, C. Niyuhire11, J. Ntamwira2, E. Ouma12, J.M. Sanginga4, C. Sivirihauma13,
R. Swennen6, P. van Asten14, B. Vanlauwe1, N. Vigheri15, and J.M. Walangululu16
1
TSBF-CIAT (Kenya), 2 INERA (DR Congo), 3 CIAT (DR Congo), 4 TSBF-CIAT (DR Congo), 5
Bioversity (Uganda), 6 KULeuven (Belgium), 7 ISAR (Rwanda), 8 CIALCA (Burundi), 9 Biover-
sity (Burundi), 10 DIOBASS (DR Congo), 11 ISABU (Burundi), 12 IITA (Burundi), 13 Bioversity
(DR Congo), 14 IITA (Uganda), 15 UCG (DR Congo), 16 UCB (DR Congo).

Abstract:
In the African Great Lakes zone, farmers are confronted by declining soil fertility, low crop yields
and food insecurity. The local crop cultivation practice entails the use of local varieties in mixed
systems with often high crop densities, and little or no application of inputs. To improve pro-
ductivity, the Consortium for Improving Agricultural Livelihoods in Central Africa (CIALCA)
implements a strategy with improved banana and grain legume germplasm as the entry point
and key component of natural resource and disease management options. Successful introduction
requires that new varieties perform superiorly in terms of yield and resistance to biotic and abi-
otic stresses in comparison with local varieties, but also match farmer expectations for traits such
as e.g., duration, taste and tradability. In addition, CIALCA sought to introduce varieties with
traits favourable for soil fertility and human nutrition. Large germplasm evaluation trials were
conducted on-station with research partners in the region, and selected varieties were evaluated
in on-farm demonstration trials to assess genotype x environment interactions and obtain farmer
feedback. Examples are given of the performance of the performance of newly introduced variet-
ies. Preferred varieties were then made available to farmers through investments in community-
led macropropation of banana germplasm, and legume seed multiplication schemes. Durable
productivity improvements however require further investment. CIALCA is promoting technol-
ogy packages that combine improved germplasm with fertilizer use, organic matter management
and/or agronomic measures. Although farmers correctly recognize low soil fertility and drought
as the major abiotic crop constraints, they rarely make use of technologies to overcome these. Fer-
tilizer is little used because of its cost and limited availability. The price of fertilizer is characteristi-
cally high due to a poorly developed agro-input sector and infrastructural constraints, but prices
of crop produce are likewise high, resulting in favourable benefit-cost ratios. This has been dem-
onstrated in all countries, in grain legumes as well as in cassava and maize intercrops, and created
interest and opportunities for fertilizer use. CIALCA further advocates appropriate organic mat-
ter management in conjunction with fertilizer use. Examples are given how quality and method
of application affect fertilizer use efficiency in climbing beans. In banana systems, mulching and
zero-tillage have positive effects on moisture retention, nutrient recycling and weed suppression,
which results in increased bunch yield even without application of external nutrients. In cassava
systems, combined application of fertilizer and green manure results in greater profitability than
the sole application of either resource. Agronomic measures can further improve yields. Optimiz-
ing the plant density and plantation management can increase banana bunch weights, but may
prolong the cropping cycle and conflict with other farmer objectives. An evaluation of water-
harvesting options suggested that benefits can be obtained from tied ridging in drought-prone
regions, but poor soil fertility is a more important constraint in maize-based systems. CIALCA
has a substantial evidence base on how the productivity of individual crop components can be
improved, but challenges remain to integrate these at system and farm level, and adjust these to
the diverse agro-ecological and socio-economic conditions of smallholder farmers. Also, the avail-
ability and affordability of fertilizer, the economic durability of community-led seed multiplica-
tion schemes, as well as the knowledge intensity of technology packages remain limitations for
large-scale dissemination and adoption.

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5. Mitigating the impact of biotic constraints to build resilient
banana systems in Central and Eastern Africa
Rony Swennen1, Guy Blomme2, Piet van Asten3, Pascale Lepoint4, Eldad Karamura2,
Emmanuel Njukwe3 and Jim Lorenzen3

1
Katholieke Universiteit Leuven, Leuven, Belgium; 2Bioversity International,
Uganda office, Kampala, Uganda; 3International Institute of Tropical Agriculture
(IITA), Uganda office, Kampala, Uganda; 4Bioversity International, Bujumbura,
Burundi

Abstract

Banana and plantain are a major food staple and source of income for food-insecure
smallholders across Central and Eastern Africa. Banana diseases and pests continue
to threaten the region’s banana production. Xanthomonas and Fusarium wilt are
widely spread across the region. Banana bunchy top disease, spread by an aphid
vector with a preference for warmer temperatures, is currently mainly present
in the Congo basin and the Rusizi valley. However, the movement of planting
materials and climate change may speed up the spread of this disease to highland
banana producing regions. Black leaf streak, nematodes and weevils, so far only
important in regions below 1,500 masl,could also potentially move to higher
elevations with climate change. Population movements during years of war/social
unrest or resettlement of refugees have often been associated with banana planting
material movement and possible disease and pest introduction. A wide range of
integrated pest and disease management (IPM) technologies has been developed
over the past years, including the introduction of resistant Musa germplasm, pest
trapping, male bud removal, disinfection of garden tools and improved canopy
and soil management. Significant progress has been achieved through research on
pest and disease epidemiology. High yielding exotic and improved varieties were
introduced via the International Transit Centre (ITC), Leuven, Belgium and the first
highland banana hybrids originating from IITA/NARO Uganda were tested across
the region. These varieties combine higher resistance with higher yields. Rapid
and healthy multiplication of banana planting material is key to a vigorous and
healthy banana sector. Farmers mostlyuse suckers, from their own or a neighbor’s
field, which are often infected by pests and diseases.Technologies for clean seed
production have been developed and disseminated, including paring of corms,
boiling water treatment, the use of macro-propagation units, and to a lesser extent
tissue culture plants. Improved linkages between research, extension, the private
sector, and policy makers from farm to regional level is required to improve the
productivity and resilience of banana systems; a critical contribution to sustainable
food systems in the region.

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6. Do commercial biological and chemical products increase crop yields
and economic returns under smallholder farmer conditions?
Jefwa, J.M.1, Asrat, A.2, Hermann, L.1, Jemo, M.3, Kavoo, A.1, Lesueur, D.4, Majengo, C.5,
Mucheru, M.6, Mukhongo1, R., Mulet6, F., Munyahali1, W., Mutegi1, E., Mwangi1, E.,
Ncho3, C., Nwoke, O.C.7, Okalebo, R.5, Pypers, P.1, Were, B.5, and Yusuf, A.8
1
Tropical Soil and Biology Institute of the International Center for Tropical Agriculture
(CIAT-TSBF), Nairobi, Kenya; 2Ethiopian Institute of Agricultural Research (EIAR), Ethiopia;
3
International Institute of Tropical Agriculture, Ibadan, Nigeria; 2Ahmadu Bello University,
Zaria, Nigeria; 4Agricultural Research for Development (CIRAD), Indonesia; 5Moi University,
Eldoret, Kenya; 6Kenyatta University, Nairobi, Kenya; 7Department of Agronomy, Osun State
University, Osogbo, Nigeria; 8Ahmadu Bello University, Zaria, Nigeria
Abstract

Smallholder farmers in sub-Saharan Africa are confronted by low crop yields due to poor soil
fertility, and only have a limited capacity to invest in inputs. During recent decennia, new
commercial products have appeared on the market as alternatives to common fertilizers. While
some of these products are based on well-established technologies, such as e.g., Rhizobium
inoculation, others have not been subjected to scientific scrutiny. During 3 years, we evaluated
over 80 of these new products, including microbial inoculants and chemical products on major
legume, cereal and banana crops across diverse agro-ecological conditions in Ethiopia, Nigeria
and Kenya. Amongst the Rhizobium inoculants, several products from different companies were
found very effective, but generally only on soybean. In Ethiopia, for example, over 30% increase
in soybean yield was found as a result of increased nodulation and N fixation. In the Nigerian
savannah zone, a similar improvement in productivity was found with three commercial strains,
which was relatively independent of soybean variety and soil type, if the soil had a low indigenous
Rhizobium population. In groundnut, contrarily, the commercial Rhizobium inoculants tested
were not only ineffective but appeared to be inferior to the indigenous soil population, independent
of the rate and source of P applied. In Kenya, inoculation increased average soybean grain yield
up to 30%, with a benefit-cost ratio up to 5.0. Responses were largest when control yields ranged
between 0.5-1.0 t ha-1, and when the soil N content varied between 0.05 and 0.15 % N. The effect
of arbuscular mycorrhizal inoculants (AMF) was less evident. No effect was observed in wheat
in Ethiopia, or on maize or soybean in Kenya. In tissue culture (TC) banana, in contrast, positive
but soil-dependent effects were found of several AMF inoculants on growth at the plantlets and
the potting stage, a crucial stage in the production process of planting material. Other products
containing Trichoderma or Bacillus spp. also had positive effects on growth. When transplanted
to the field, soil-dependent growth improvements of over 40% were observed, demonstrating
that TC bananas can indeed benefit from commercial biological products. On-going work is
elucidating the interactions with pathogenic rhizosphere organisms, particularly Fusarium, on
which the inoculants have variable and soil-dependent effects. Amongst the chemical products
evaluated, special attention was given to alternative P fertilizers such as leaf sprays, seed coatings
and conditioners with humic acids. The effect on cereals depended on the crop, the soil and
accompanying agronomic measures. In Ethiopia, positive effects in wheat were only found with
the humic acid conditioner. In Nigeria, both humic acid conditioners and leaf sprays increased
maize grain yield, but the effect of the leaf sprays was highly site-dependent and the cost of the
humic acid conditioner was not compensated by the benefits on yield. In Kenya, positive effects
were found only if products were combined with fertilizer at a sub-optimal rate, and only in the
most P-deficient soils. Benefit-cost ratios were only favourable for seed P coating because this is a
fairly inexpensive treatment (3 USD ha-1). In conclusion, results demonstrate that there is potential
for biological and chemical commercial products, but there is need for continued evaluation.
Smallholders may benefit from some of these products, on the condition that a good-quality
product is correctly applied to the appropriate crop with appropriate soil and crop management.

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7. Enhanced utilization of biotechnology research and development
innovations in eastern and central Africa
Masiga, C. W.1, Ketema S.1 and Mugoya C.1

1
Associationfor Strengthening Agricultural Research in East and Central Africa
(ASARECA), Entebbe, Uganda

Abstract

The association for strengthening agricultural research in east and central Africa
(ASARECA) through its Agrobiodiversity and biotechnology programme is
enhancing utilization of biotechnology research and development innovations in
ECA. This is achieved through support to national agricultural research systems.
The programme supports generation and uptake of biotechnology innovations,
capacity strengthening, and availability of information. The successes so far are
impressive. Cassava transformation platforms in Kenya, Uganda and Tanzania have
been established to Biosafety level II status and have become regional research and
training epicentres in biotechnology. Low cost tissue culture protocols for cassava
and sweetpotato have been developed for banana, sweetpotatoes and cassava.
Virus indexing tools have been developed for screening banana, cassava and
sweetpotatoe planting materials against the common diseases and pests. Production
and dissemination of clean banana tissue culture has been strengthened. A regional
genebank utilizing conservation biotechnology for conservation of cassava and
sweetpotatoes is being rehabilitated and refurbished at the National Gene bank
of Kenya. A parallel research activity involving development of a genetic linkage
map to map the location of the genes that confer resistance to cassava brown streak
disease (CBSD) is underway. Drought tolerant transgenic maize has been developed
for seven farmer preferred maize lines for Kenya, Sudan, Tanzania and Ethiopia.
Marker assisted selection has been used to generate 51 sorghum lines resistant to
striga. Fine mapping of sorghum for striga resistance is almost completed. A pen-
side diagnostic kit for detection of Taenia solium cysticercosis has been developed
in ECA and the vaccine is under going trial. A number of post graduate trainings
have been supported. Information on these technological breakthroughs is being
developed and will be published through books, journals and workshops.

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8. Production of virus free sweetpotato planting materials using
horticultural fleece
Schulte-Geldermann, E. 1, Omuse, O.P.2, Agili, S. 1 and Low, J.1

International Potato Center (CIP), Nairobi, Kenya; 2Moi University, School of
1

Agricultural sciences, Eldoret, Kenya

Abstract

Sweetpotato (Ipomea batatas) is one of the most important staple crops in densely
populated parts of Eastern Africa and is quickly becoming an important
supplementary staple in the southern part of the continent. It is vital to small scale
farmers with limited land, labor and capital. One of the major yield limiting factors
in sweetpotato production are lack of clean planting material owing to infection of
Sweetpotato virus diseases (SPVD). Therefore there is a need to provide farmers
with better technologies for rapidly multiplying clean planting materials and
maintaining a clean stock for a long period on-farm without compromising on the
quality. An experiment was set at Kakamega agriculture research station, in Kenya
from June 2009 to March 2011. Three varieties of sweet potato free from virus but
susceptible to SPVD have been evaluated in three methods of vine multiplication a)
control -exposed, b) Fleece-cover and c) Fleece-tunnel. In an interval of 5 months
cuttings have been taken and tested for virus incidence. Furthermore, cuttings were
replanted to measure the effect on field performance. Results indicate significant
reduction in aphid, white fly population and virus levels, and a significant higher
production of vine cuttings from the second cutting onwards. However, direct fleece
cover led to heat damage on vines which couldn’t be observed in the tunnel. Yields
from vines obtained from both covering treatments have been significantly higher
than from vines out of the exposed treatment with all varieties. Preliminary data
reveal that the use of horticulture fleece could act as a cheap measure to maintain
virus free foundation seed.

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9. Lessons from Upstream Soil Conservation Measures to Mitigate
Soil Erosion and Improve Land Productivity in the Humid
Highlands of Northwestern Ethiopia
Mengesha, Y.G.S.1 and Tadele, A.2

Department of Natural Resources Management, College of Agriculture and Environ-
1

mental Science Bahir Dar University, Bahir Dar, Ethiopia; 2 Department of Natural
Resources Management, College of Agriculture and Natural Resources, Debremarkos
University, Debremarkos, Ethiopia

Abstract

A study was conducted in Absela site, Banja Shikudad district, Awi administrative
Zone of the Amhara National Regional State (ANRS), Northwestern Ethiopia located
in the Blue Nile Basin to evaluate the effects of soil bunds stabilized with vetiver grass
(V. zizanioides) and tree lucerne (C. palmensis) on selected soil physical and chemical
properties, bund height, inter-terrace slope and barley (Hordeum vulgare L.) yield. The
experiment had five treatments that included non-conserved land (control), a 9-year
old soil bund stabilized with tree lucerne, a 9-year old soil bund stabilized with vetiver
grass, a 9-year old sole soil bund, and a 6-year old soil bund stabilized with tree lucerne.
Data were analyzed using one-way analysis of variance (ANOVA) and mean values
for the treatments were separated using Duncan Multiple Range Test. Results of the
experiment indicated that OC, total N, bulk density, infiltration rate, bund height, and
inter-terrace slope are significantly (p≤0.05) affected by soil conservation measures.
The non-conserved fields had significantly lower OC, total N, infiltration rate; whereas
higher bulk density as compared to the conserved fields with different conservation
measures. However, no significant differences in bulk density were observed among the
conservation methods. The field treated with 9-year old soil bund stabilized with tree
lucerne or sole soil bund had significantly higher OC content than all other treatments.
Fields having 6-year old soil bunds had lower OM and total N when compared to fields
having 9-year old soil bunds irrespective of their method of stabilization. Fields with soil
bunds stabilized with vetiver grass had the highest bund height and the lowest inter-
terrace slope than fields with the remaining conservation measures. Barley grain and
straw yields were significantly (P<0.05) greater in both the soil accumulation and loss
zones of the conserved fields than the non-conserved (control) ones. In the accumulation
zone, fields with the 9-year old soilbund stabilized with tree lucerne and with the
9-year old sole soil bund gave higher grain yields (1878.5 kg ha-1 and 1712.5 kg ha-1,
respectively) than fields having 9-year old soil bund stabilized with vetiver grass (1187
kg ha-1) and 6-year old soil bund stabilized with tree lucerne (1284.25 kg ha-1). When
we compare the accumulation and the loss zones, the average grain yield obtained from
the accumulation zones (averaged over all the treatments) was by 29.8% higher than the
average grain yield obtained from the loss zones. The causes of soil erosion in the region
could be rugged nature of the topography, high and erratic rainfall pattern, extensive
deforestation, continues cultivation and complete removal of crop residues from the
field, over and free grazing, improper farming practices and development efforts, over
population and poverty, socio- economic problems, lack of awareness on the effect of
erosion and poor land use policy enforcement.

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20


THEME 2: SYSTEM
COMPONENTS

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22


10. Tradeoffs analysis in the design of integrated resource
management strategies for smallholder farming systems in the
African highlands
Pablo Tittonell

Agricultural Research for Development (CIRAD), Montpellier, France

Abstract

Smallholder farming systems are diverse, spatially heterogeneous and dynamic. They
operate in uncertain and changing environments to which they need to adapt constantly.
Resources and investments are often limited, and their strategic allocation in space and
time impacts on system attributes such as efficiency, vulnerability and resilience in the
short and long terms. Any technological strategy aiming to improve system performance
and sustainability should be designed considering the integrated nature of smallholder
farming systems, particularly in the case of mixed crop-livestock farming. Relatively
high agroecological potential and moderate tropical climate attracted preferential human
settling in the African highlands, often resulting in mixed smallholdings in which the
crop subsystem may be annual, perennial or both, and the livestock subsystem may
range from communal grazing to cut-and-carry practices. Dense human population,
coupled with lack of resources and sometimes inadequate agricultural practices often
resulted in resource degradation at farm and landscape levels, and conflict over the
control and utilization of communally owned resources. The design of management
strategies should consider resource interactions at different scales, from farms, to
landscapes or territories. Yet, interactions at the scale of field plots or livestock units
are central, as biophysical responses and affordability and are key determinants of
technology adoption. Beyond their impact on the system as a whole, technologies must
be effective, exhibit a positive impact on the subsystem they target, and fit within local
socio-economic contexts and livelihood systems (self-subsistence, market-orientation,
off-farm employment, etc.). Decisions on the allocation of scarce resources within the
farming system entail tradeoffs of different nature, which must be quantified to better
inform the design of integrated resource management strategies. While smallholder
farmers are system managers by nature, system integration remains a major challenge
in the field of agricultural research. Disciplinary standpoints, institutional interests and
different scales of analysis may often lead to competing research efforts, disaggregated
results, replication of old experiences and/or impractical recommendations. Although
integrative approaches have been proposed in the field of agronomy over the last two
decades: Integrated Pest Management (IPM), Soil Fertility Management (ISFM), or Crop
Management (ICM), their acronym has been frequently misused. Taking ISFM as an
example, we may find a long list of examples in which the term is used to describe
disciplinary research that ignores the integrated nature of smallholder farming systems.
This presentation will discuss examples of system integration in agricultural research
through tradeoffs analysis at different scales, with the aid of participatory field research
and bio-economic simulation modeling, placing emphasis on ISFM technologies.
Whole-system properties of interest that emerge in integrated analyses (e.g., system
organisation, complexity and throughflows) will also be examined.

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11. CIALCA’s efforts on integrating farming system components
and exploring related trade-offs
P. van Asten1, B. Vanlauwe2, E. Ouma1, P. Pypers2, J. Van Damme3, G. Blomme4, P.
Lepoint5, J. Ntamwira6, H. Bouwmeester7, E. Birachi8, L. Jassogne3, T. Muliele9, S. Bi-
zimana10, A. Nibasumba10, S. Delstanche3, P. Baret3, J. Sanginga11, F. Bafunyembaka11, M.
Manzekele6

1
IITA, Kampala, Uganda; 2TSBF-CIAT, Nairobi, Kenya; 3Université Catholique de
Louvain, Louvain-la-neuve; 4Bioversity International, Kampala, Uganda; 5Bioversity
International, Bujumbura, Burundi; 6INERA/CIALCA, Mulungu, DR Congo; 7IITA,
Dar es Salaam, Tanzania; 8CIAT, Kigali, Rwanda; 9INERA/CIALCA/UCL, Mulungu,
DR Congo; 10ISABU/CIALCA/UCL, Bujumbura, Burundi Belgium; 11TSBF-CIAT,
Bukavu, DR Congo

Abstract

The densely populated humid East African highlands of East DRC, Rwanda, and
Burundi are characterized by small farms (<1ha), large families (7 people), few livestock
(0.4 TLU), high illiteracy, and a large dependence on a few staple food crops such as
cassava, bananas, and beans. Farmers wish to improve their food security and income,
but have limited resources to achieve this. Farming system components interact,
especially in environments where resources (e.g land, labour, capital, nutrient inputs)
are in short supply. To better understand constraints and opportunities to improve
the farming systems, farmers can be clustered in farm typologies with similar traits.
In the CIALCA area, few farmers belong to the “resource-rich entrepreneurs” and
most farmers are “resource-constrained”, particularly in East DRC and Burundi. The
“natural-resource rich” farmers have relatively large land holdings and livestock units
but are often remotely located and subsistence oriented. CIALCA has made an effort
to improve the resource use efficiency at farm level, by exploring and improving the
interactions between some of the dominant farming system crop components. The aim is
to achieve triple-wins of improved food production, income, and natural resource base.
For the annual crops, new planting arrangements have been developed for cassava-
legume and maize-legume systems. When combined with judicious applications of
mineral fertilizers and organic matter inputs, production and income is often doubled.
However, the ‘best’ combination depends on the agro-ecological region and within farm
soil fertility gradients. For the perennial-based systems, we improved legume intercrop
production by reducing the banana leaf numbers. This is particularly needed for the
more light-demanding legumes such as climbing beans and soybean in the high rainfall,
better soil fertility areas near the Albertine rift. Our studies on intercropping banana and
coffee suggest large agronomic benefits at farm level and the technology is appealing for
farmers who wish to combine food and cash crops to cover their needs. In general, the
integrated technologies proposed are knowledge intensive and the applicability shows
strong spatial variation. In addition, investments related to soil and water conservation
and use of perennials do often not offer much short-term benefit, which makes adoption
difficult for the resource-poor and risk-averse farmers. As a result, achieving impact
through the proposed integration packages requires a favorable policy, extension, and
market environment. Constraints in these environments are often a constraint for the
scaling out of improvements at the farm level

24


12. Trade Costs reduction in the Congo Basin: Impact on crop land
expansion and agricultural productivity growth
Mosnier, A. 1, 2, Havlik, P.1,3, Obersteiner, M.1, Aoki, K.1, Schmid, E. 2
1
International Institure for Applied Systems Analysis (IIASA), Laxenburg, Austria;
2
University of Natural Resources and Applied Life Sciences (BOKU), Vienna, Austria;
3
International Livestock research Institute (ILRI), Nairobi, Kenya

Abstract

If most of the Congo basin benefits from very suitable conditions for agriculture, yields are
much lower than in other tropical regions as Brazil or Indonesia and subsistence farming is
still dominant. One major bottleneck of agriculture development is the poor availability and
quality of infrastructure. Many studies suggest that the importance of subsistence agriculture
is partly due to high transaction costs which make the sales out of the farm not profitable
and limit the possibilities to get food from other sources (A. Ruijs et al., 2003; P. Buys et al.,
2006). Furthermore, better transportation infrastructure can facilitate access to inputs and
capital and improve labor productivity through a better access to social infrastructures as
schools and health centers (Thirtle et al., 2003; Oshikoya and Hussain, 2002). But at the
same time, the strong impact of road expansion on deforestation has been highlighted (Geist
and Lambin, 2002; Freitas et al., 2009; Pfaff, 1999). Forest covers approximately 80 % of the
basin (GLC2000) with more than half classified as dense forest. In a context of fast growing
population – population of Congo basin could reach 170 million inhabitants in 2030 (IIASA-
SRES) – and high international commodity prices, agricultural sector faces strong incentives
to grow. For the next decades food security, economic development and forests protection
are high in the agenda and the increase in agricultural productivity is often viewed as the
only way to reconcile these objectives. We use GLOBIOM, a global partial equilibrium model
which integrates the main land based sectors i.e. agriculture, forestry and bioenergies (Havlík
et al., 2010) to simulate the impact of future investments in transportation infrastructures
on the development of the agricultural sector in the Congo Basin. Land use modeling is
based on land characteristics with a very detailed representation -more than 6000 simulation
units- in the Congo basin. This allows us to spatially differentiate the impact of infrastructure
development on agriculture and land use change through two channels of transmission: the
price of the fertilizers and the price of the farm products. Moreover, GLOBIOM is a global
model where Congo Basin region is connected to the other regions through international
trade. Then, the reduction of the price of locally produced goods change the tradeoff between
imports and local goods for domestic consumption and the competitiveness of Congo Basin
exports on international markets. Simulations are made by 2030. We include in our database
the transportation infrastructure projects in the Congo Basin for which a funding is already
planned and recompute the internal transportation costs on this new basis. We run the model
for two variants: 1) there is no limit on deforestation; 2) a limit on GHG emissions from
deforestation is introduced. Finally, a sensitivity analysis is made on the transportation costs
reduction due to the uncertainty related to the effective transmission of the reduction of
the costs to the customer price. Infrastructure improvement is especially beneficial for crops
with high yields in areas which were very remote before. This is especially true in the case of
cassava and sugarcane in the Democratic Republic of Congo. The preliminary results -without
the transmission of reduced transportation costs on fertilizers- show that agricultural sector
is fostered but that productivity increase is very limited. Most of the increase in agricultural
production is achieved through cropland expansion: the total deforested area is multiplied
by three. The introduction of limits on deforestation considerably reduces the positive impact
of infrastructure improvement on agriculture and leads to higher food imports and food prices. These
results imply that costs associated with more productive systems are currently very high in
the Congo Basin and that the only market forces will lead to higher deforestation and limited
productivity increase.

25


13. Using the ‘livestock ladder’ to exit poverty for poor crop-livestock
farmers in South Kivu, eastern DR Congo
Brigitte L. Maass1, Wanjiku L. Chiuri2, Rachel Zozo3, Dieudonné Katunga-Musale3 and
Eliud Birachi2

CIAT (Centro Internacional de Agricultura Tropical), Nairobi, Kenya; 2CIAT/CIALCA,
1

Kigali, Rwanda; 3 CIAT/CIALCA, Kasongo, Commune d’Ibanda, Bukavu, DR Congo;

Abstract

Small animals dominate in South Kivu, DR Congo after decades of war and unrest.
We applied different survey instruments to assess the current situation of livestock
production in the region such as a diagnostic survey, participatory rural appraisal
(PRA) and value chain (VC) analysis along a North-South and Southwestern axis
around the provincial capital Bukavu. Mean livestock was only 1.84 TLU per livestock
holder. Monogastric animals in smallholder farms are produced in very flexible
backyard systems. They are characterized by small numbers of chicken and/or cavies
or pigs. Monogastric animals are traditionally fed by household wastes and other feeds
sourced by scavenging around the homestead (e.g., seeds, insects, worms); only 10% of
the chicken and even less of pigs received small complements of maize. Monogastric
animals are usually underfed under these conditions. Thus, productivity is low but
the system provides a steady source of high quality animal protein in the form of eggs
and meat for household consumption and, consequently, helps to enhance nutrition
security. The majority of peasants does not produce sufficient livestock throughout the
year to have surplus for regular sales, thus, local production is even too low to satisfy
subsistence. Farmers only sell when needs arise. Sales take place on local or regional
markets, but rarely reach Bukavu, at a distance of 20-80 km. However, the current road
infrastructure is not conducive to gain access to this urban population of more than
500,000 inhabitants. Recently, trans-border provision of products has become significant
in South Kivu; the urban meat market is supplied by producers from nearby Rwanda or
even Uganda and Kenya. Humanitarian assistance during the past decades of war and
unrest seems to have discouraged peasants from taking own initiatives; they are rather
receptive to any kind of donation. The challenge under these conditions is to start to
enhance production. We suggest to invest and investigate into the lowest rung of the
‘livestock ladder’ by improving the small animal systems emphasizing the provision
of dry season feed, which was raised as a major issue. Applying participatory variety
selection (PVS) on small plots in four locations, farmers chose forages with visible dry
season-tolerance, but also those palatable for their small animals, like the herbaceous
legume Canavalia brasiliensis. By including leguminous forages in farming systems, soil
fertility will improve. Soil fertility management was traditionally based on manure.
Increasing livestock stocking rates will also help to improve crop productivity. The
potential role of forages needs to be assessed in a systems context by identifying spatial
and temporal niches in addition to their potential acceptability by local farmers. We
suggest to use a participatory scenario modelling approach focusing on small animals
and feed systems to re-connect South Kivu farmers to the market. The final outcome will,
hence, be better nutrition of family members, provision of cash income and, eventually,
support for the acquisition of larger animals.

26


14. N2Africa: Putting nitrogen fixation to work for smallholder
farmers in Africa
Giller Ken1, Vanlauwe B2, Baijukya F2, Franke L1 and Bala A3

Plant Production Systems, Wageningen University, Wageningen, The
1

Netherlands; 2Tropical Soil and Biology Institute of the International Center for
Tropical Agriculture (CIAT-TSBF), Nairobi, Kenya; 3International Institute of
Tropical Agriculture (IITA), Ibadan, Nigeria

Abstract

Maximal rates of N2-fixation recorded in the tropics reach an astonishing 5 kg N
ha-1 day-1. We have measured more than 250 kg N ha-1 of fixed N2 in soyabean
in southern Africa with associated grain yields of more than 4 t ha-1. But often less
than 5 kg N ha-1 year-1 is fixed by legumes at farm scale in African smallholder
systems. Increase of inputs from nitrogen fixation is required to achieve the
increases in productivity required as part of the African green revolution that is
gaining momentum. Successful N2-fixation by legumes in the field depends on the
interaction: (GL × GR) × E × M that is (legume genotype × rhizobium genotype)
× environment × management. Environment encompasses climate (temperature,
rainfall, daylength etc) and soil stresses (acidity, aluminium toxicity, limiting
nutrients etc). Management includes aspects of agronomic management (use of
mineral fertilizers, sowing dates, plant density, weeding). Although much research
is focused on identifying best combinations of GL and GR, the E and M factors
often override the potential of the legume/rhizobium symbiosis for N2-fixation.
Attention will be focused on identifying new socioecological niches for fitting grain,
forage and tree legumes into existing farming systems, and the conditions necessary
to achieve successful N2-fixation. The N2Africa project aims to increase inputs
from N2-fixation on more than 225,000 smallholder farms across eight African
countries within four years through: a) Increasing the area of land cropped with
legumes; b) Increasing legume productivity through better agronomy and basal
(P, K etc) fertilizer; c) Selecting and disseminating legume varieties with increased
N2-fixation; d) Selecting better rhizobium strains and promoting high quality
inoculants; e) Linking farmers to markets and creating new enterprises to increase
demand for legumes. N2Africa has already reached more than 25,000 farmers and
the latest learnings will be discussed.

27


15. The 4R Nutrient Stewardship in the context of smallholder
agriculture in Africa
Zingore Shamie1 and Johnston Adrian2

1
International Plant Nutrition Institute, Africa Program, Nairobi, Kenya;
2
International Plant Nutrition Institute, Canada

Abstract

In the face declining crop productivity and a growing food insecurity, there are
renewed efforts to support smallholder farmers in sub-Saharan Africa (SSA)
intensify crop production, in particular by increased fertilizer use. Successful
agricultural intensification will depend to a large extent on proper management
of plant nutrients to increase fertilizer use efficiency (agronomic N use efficiency
value are often less than 15 kg grain /kg N for maize in farmers’ fields). The 4R
Nutrient Stewardship Framework developed by the fertilizer industry worldwide
aims to provide the context for efficient on‐farm nutrient management practices
with irreducible simplicity focused on four central components: applying the right
fertilizer source at the right rate, at the right time in the growing season, and in
the right place. Smallholder farms in SSA exhibit substantial heterogeneity in soil
fertility within short distances, and the 4R Nutrient Stewardship should address this
variability to increase nutrient use efficiencies. Although fertilizer recommendations
in SSA mostly cover N and P only, analysis of nutrient deficiencies show an increase
of constraints to crop production with decreasing soil fertility status. Depleted soils
that cover wide areas are associated with multiple nutrient deficiencies and addition
of the ‘right’ fertilizer sources that provide base cations (K and Ca) and micronutrients
(Zn and B) in addition to N and P is required to significantly increase yields. The
‘right rate’ of fertilizer application has also been found to have profound effects
on nutrient use efficiency, with on farm experiments showing that agronomic and
economic returns diminish rapidly on most poor soils when nutrient applications
rates exceed 60 kg N/ha and 10 kg P/ha. In addition to the standard timing of basal
and top dressing fertilizer application, ‘right time’ of fertilizer application in SSA
should be flexible and adjustable to the highly variable inter- and intra-seasonal
rainfall as a risk mitigation strategy. The ‘right place’ is often critical when low
rates of fertilizer are used, with spot-application more effective at placing nutrients
where crops can use them effectively. Each of the four “rights” is directly related to
the other three in at least one way, interconnected into a unified, effective system.
When viewed holistically, 4R Nutrient Stewardship can have far-reaching effects on
the sustainability of agricultural systems in SSA beyond the immediate benefits in
terms of crop productivity.

28


16. Building “climate smart” East African coffee production systems
Henk van Rikxoort1,2, Laurence Jassogne3, Peter Laderach1 and Piet van Asten3

1
Wageningen University and Research Centre (WUR), Development and Rural In-
novation, The Netherlands; 2International Center for Tropical Agriculture (CIAT), De-
cision and Policy Analysis Program (DAPA), Nicaragua; 3International Institute of
Tropical Agriculture (IITA), Kampala, Uganda

Coffee is a major cash crop in the tropical humid highlands of East Africa and is mostly
cultivated by smallholder farmers. Here, it contributes significantly to their income se-
curity but also to the national economies of the region. Coffee can be found cultivated
in different agricultural systems ranging from monocultures to polycultures with shade
trees and additional food crops. Global Circulation Models (GCM) generally predict an
increase in temperature and more rainfall in the region. Rainfall is predicted to become
more erratic and as a consequence, short periods of drought will be more common, pos-
sibly with less distinct dry seasons. These predictions can have drastic consequences
on coffee production and coffee quality because coffee relies on very distinct dry and
wet seasons for flowering and cherry maturation. Therefore, climate change will have
a direct impact on the productivity of the coffee system and therefore on the farmers
livelihoods. For smallholder coffee farmers, polyculture systems often are more resilient
than monocrop systems, this is through a reduction of income and food risks, while
adapting at the same time to extreme climate events such as drought and high tempera-
tures. A carbon footprint analysis also shows that besides coffee suffering from a chang-
ing climate it also contributes to climate change itself. Carbon footprint standards have
emerged as new market requirements for producers of agri-food products to retailers in
developed countries and are likely to become a comparative advantage. Based on these
two dynamics we compared both the adaptive capacity and the carbon footprint of sev-
eral East African coffee production systems. First, coffee systems in East Africa are de-
scribed and characterized by comparing them with coffee systems in Central America.
Following this, the productivity, resilience and adaptation potential to climate change
of these systems are analyzed. Finally, the carbon footprint of the various systems based
on data from East Africa and Latin America is estimated and discussed. The results
highlight the importance of sound adaptation strategies along the coffee value chain in
order to come to a sustainable coffee production in East Africa in short, medium and
long term.

29


30


THEME 3: DRIVERS FOR
ADOPTION

31


32


17. Drivers of productivity growth in Africa: implications for
enhancing adoption of improved technologies
Langyintuo Augustine,

Alliance for a Green Revolution in Africa (AGRA), Nairobi, Kenya

Abstract

The contribution of technological change to agricultural productivity and rural
transformation in many developing countries sometimes by-passes many rural
populations in Africa due to institutional and technical constraints. Consequently,
the dream of improving the livelihoods of rural farm households in Africa dependent
on agriculture would remain an illusion if the adoption rates of proven technologies
remain low. While highlighting the main causes of the poor performance of
agricultural productivity in Africa to be a combination of low use of improved
technologies (mainly seeds and fertilizers), historical factors such as structural
adjustment, poorly developed markets, lack of political support, among others, this
paper argues for strong private-public partnership to drive productivity growth,
transform rural economies and improve household livelihood and incomes.

33


18. Drivers of technology adoption in the banana-legume systems in
the East and Central Africa region
E. Ouma1, E. Birachi2, V. Kasereka3, H. Garming4, I. Macharia5, P. Van Asten6, A.Chifizi7,
M. Nyagaya8, B. Ekesa9, J. Van Damme10, B. Vanlauwe11, G. Blomme9, M.C. Niyuhire12,
L. Ndimurirwo12, J. Ochieng1, T. Dubois6, P.Pypers11, L. Wairegi6, C. Ruraduma12, A.
Bizoza7, and M. Maertens13
1
International Institute of Tropical Agriculture, Bujumbura, Burundi; 2TSBF-CIAT, Kigali,
Rwanda; 3CIALCA, Bukavu; 4Bioversity International, Costa Rica; 5Jomo Kenyatta University of
Agriculture and Technology, Kenya; 6International Institute of Tropical Agriculture, Kampala,
Uganda; 7Rwanda Agricultural Board, Rwanda; 8TSBF-CIAT, Kampala Uganda; 9Bioversity In-
ternational, Kampala, Uganda; 10Universite Catholique de Louvain-la-Neuve, Belgium; 11TSBF-
CIAT, Nairobi, Kenya; 12Institut des Sciences Agronomiques du Burundi (ISABU), Burundi;
13
Katholieke Universiteit Leuven (KU Leuven)

Abstract

Many interventions to improve productivity of agricultural systems have been promoted
in the Great Lakes Region of Africa through technological change. The expected benefits
of such technologies however remain limited and in some cases do not reach the
intended beneficiaries due to technical and institutional constraints. The Consortium for
Improving Agricultural Livelihoods in Central Africa (CIALCA) promotes productivity
enhancing technologies in the region with components of improved banana and legume
germplasm coupled with natural resource and disease management strategies based
on participatory approaches. CIALCA has applied the Production-Consumption
continuum to link system value chain actors, from inputs required for production to
delivery to the consumers, while addressing key drivers that affect the process. The
market linkage approach has been used to drive the uptake of banana and legume
technologies through collective efforts among smallholder farmers. The result has
been a marked increase in potential productivity of the production systems based on
demonstration and control field trials. The interventions if adopted have positive effect
on the overall goals of alleviating poverty and improving nutritional health among the
population. CIALCA has conducted a comprehensive study to map out the pathways
for technology uptake and dissemination as well as factors that are likely to drive or
enhance the uptake of technologies in the region. Results show that in order to achieve a
critical mass in agricultural technology adoption, social factors, policy and institutional
environment need to be favorable. Local institutions, grassroot level collective action
and agricultural development partners play a critical role in technology dissemination.
Accessibility by farmers to appropriate inputs for production has also been assessed in
the region and results indicate that input prices, tax levies and level of development of
distribution networks influence input use. The need for government support through
appropriate policies is thus emphasized. Results further reveal that market access and
support services in the form of extension services and credit access through functional
financial markets influences technology adoption. This shows that certain institutional
factors as well as transaction cost factors need to be addressed to motivate uptake of
technologies. Potentials of large scale private sector linkages that can fill identified gaps
to enhance technology adoption is highlighted.

34


19. The agro-ecological solution!? Food security and poverty
reduction in sub-Saharan Africa, with an emphasis on the East
African Highlands
Henk Breman

International Fertilizer Development Centre (IFDC), CATALIST project, Burundi

Abstract

In a recent report, Olivier de Schutter, “Special UN Reporter on the Right to Food”,
insists that the adoption of the agro-ecological approach can double food production
by smallholders in poor and vulnerable regions of our world. He considers them
superior to conventional agriculture based on chemicals and proposes measures for
Governments leading to the development and adoption of such approaches. The
basis for this opinion is weak. The average relative production increase is misleading
when the effect is far the highest for original yields between 0 - 0.5 t/ha, serious
errors are made in key background papers, and the contribution to agricultural
sustainability will be undermined by increasingly negative soil nutrient balances.
The risk exists that the UN report will become co-responsible for increasing famine
and poverty in sub-Saharan Africa. If, however, a recommendation is added,
promoting the adoption of agro-ecological approaches for improving the efficiency
and the accessibility of inorganic fertilizers, instead of suggesting replacing the latter,
an entirely different perspective is created. The chance of seeing a rapid adoption
of more productive, more remunerative and more sustainable production systems
in sub-Saharan Africa increases considerable. In particular when the inherent
agronomic recommendations become part of value chain development efforts, food
security can be rapidly obtained in the region. Even for Somalia there is hope. To
substantiate the above statement, the analyses of the De Schutter report and some of
the background studies, will be combined with results of the promotion of integrated
soil fertility management in a value chain development context in Central Africa’s
Great Lakes region. A rapid diffusion of agriculture intensification technologies is
observed, and those applying inorganic fertilizers in combination with organic and
other soil amendments produce even in dry years.

35


20. Exploring the scope of fertilizer use in the East African region
Wairegi, L.W.1, van Asten, P.J.A.2

Centre for Agriculture and Biosciences International (CABI), Africa Regional Centre,
1

Nairobi, Kenya; 2International Institute of Tropical Agriculture, Kampala, Uganda

Abstract

Nutrient removal exceeds nutrient replenishment in much of sub-Saharan Africa’s ag-
riculture. Furthermore, use of mineral fertilizers is low as fertilizers are often consid-
ered expensive and not accessible to smallholder farmers. The diversity of the crops and
cropping systems in sub-Saharan Africa further complicate farmer decisions on input
use. Decision support tools for use by farmers in deciding types of crops to grow and
amount and type of soil inputs required are in most cases not available to farmers. This
paper explores the expected benefits of fertilizer by relating value of yield to the value
of fertilizer equivalent of nutrients removed for selected crops (maize, beans, bananas,
cassava and coffee), in the East African region. It further explores how changes in farm-
gate prices and fertilizer costs can affect the expected benefits. Between mid 2010 to mid
2011, fertilizer was least expensive in Rwanda (e.g. Urea 540 USD/t), Kenya (e.g. Urea
541 USD/t) and Tanzania (e.g. Urea 558 USD/t) compared with other countries in the
region (Urea ≥712 USD/t). Farm-gate prices varied up to 80% among regions within
countries. Assuming nutrient recovery efficiencies of 50%, 15% and 60% for N, P and
K, respectively, the amount of single-nutrient fertilizers (Urea, Triple Super Phoshate,
Muriate of Potash) required to increase yield by one ton edible dry matter is estimated
to range between 214kg (for rice) and 900 kg (for banana). The ratio between average
price of one ton of yield and average cost of fertilizer required to increase yield by one
tonne ranged between 1.1 (banana) and 5.0 (rice) in Burundi, 0.8 (cassava) to 8.1 (coffee)
in Kenya, 1.0 (maize) to 6.7 (rice) in Rwanda, 0.7 (cassava) to 7.6 (coffee) in Tanzania, 0.6
(cassava) to 4.3 (rice) in Uganda, 1.1 (banana) to 4.7 (rice) in the Democratic Republic of
Congo. These ratios increased by between 100% and 896 when calculations were based
on nutrients removed in edible yield and not on total above ground biomass. The ratios
for beans ranged between 2.9 (Rwanda) and 4.0 (Burundi and Tanzania ) and increased
to between 3.9 (Rwanda) to 5.5 (Burundi) when 50% of the N requirements were as-
sumed to be met through biological nitrogen fixation. We conclude there is need and
scope for fertilizer use in the East African region, but choice of crop for intensification,
and decision on amount and type of fertilizer should depend on input/output prices,
residue management, and crop response. We also conclude that in cropping systems
where more than one crop is grown, intensification in one crop can be beneficial to other
crops in the system.

36


21. Supply and demand drivers of grain legumes in highlands
of central and southern Africa: Implications for targeting
agricultural research investments
Rusike Joseph1, Boahen Steve K.2, Dashiell Kenton3, Kantengwa Speciose4 and Ongoma
Josephine5

1
International Institute of Tropical Agriculture, Lilongwe, Malawi; 2International
Institute of Tropical Agriculture, Nampula, Mozambique; 3Tropical Soil and Biology
Institute of the International Center for Tropical Agriculture (CIAT-TSBF), Nairobi,
Kenya; 4CIALCA, Kigali, Rwanda; 5Kleen Homes and Gardens, Migori, Kenya

Abstract

The highland areas of central and southern Africa are endowed with favorable
agro-ecological conditions for production of grain legumes. There is increasing
evidence that rapid population growth is increasing population densities and these
are resulting in Boserupian changes. These include soil fertility mining, soil erosion,
land degradation, deforestation and poverty traps. Smallholders are failing to
exploit the opportunities. There is a growing interest in expanding the share acreage
annually planted to legumes for sustainable intensification and diversification while
maintaining soil health. This study uses rapid assessment value chain surveys to
analyze the supply and demand drivers driving changes, identify opportunities and
constraints for expanding production and draw implications for targeting research
investments. We find that significant opportunities lie in supplying grain legumes to
domestic urban markets and export to regional and international markets. Different
countries are at different stages of development. The major constraints on expanding
production and marketing of the grains include low yields, production and quality
of products; uncompetitive farm gate prices; poor market coordination; the lack of
agro-processing, storage, and microfinance; and poor government policies. The
incidence and severity of constraints and priority research interventions to resolve
them vary with the stage of development of the value chains of grain legumes in the
country.

37


22. Assessing nutritional diversity of cropping systems in Africa
Remans Roseline1, Flynn Dan3, DeClerck Fabrice3, Nziguheba Generose1 and Palm
Cheryl4

1
Earth Institute, Columbia University, New York, USA; 2Leuven Sustainable Earth,
Katholieke Universiteit Leuven, Belgium; 3Department of Ecology, Evolution, and En-
vironmental Biology, Columbia University, New York, USA

Abstract

Background: In Sub-Saharan Africa, 40% of children under five years in age are
chronically undernourished. As new investments and attention galvanize action
on African agriculture to reduce hunger, there is an urgent need for metrics that
monitor agricultural progress beyond calories produced per capita and address
nutritional diversity essential for human health. In this study we demonstrate how
an ecological tool, functional diversity (FD), has potential to address this need and
provide new insights on nutritional diversity of cropping systems in rural Africa.
Methods and findings: Data on edible plant species diversity, food security and diet
diversity were collected for 170 farms in three Millennium Villages in Sub-Saharan
Africa. Nutritional FD metrics were calculated for macronutrients, vitamins, and
minerals, based on farm species composition and species nutritional composition.
Iron and vitamin A deficiency were determined PalmNutritional FD metrics
summarized the diversity of nutrients provided by farms and gives unique insights
in nutrient differences across farms and villages. Regression of FD against species
richness and expected FD allowed identification of key species adding nutrient
diversity to the system and assessment of the degree of redundancy for nutritional
traits across farms and villages. Nutrition FD metrics further showed that depending
on the original composition of species on farm or village, adding or removing an
individual species can have radically different outcomes for nutritional diversity.
Analysis of the relationship between nutrition FD metrics and household nutrition
indicators proposes new hypotheses on the link between agro-diversity, food
security and human nutrition as well as strategies for future research that emphasize
landscape-scale interdisciplinary approaches. This study delivers a novel metric to
address nutritional diversity in agricultural systems and provides a set of examples
that can help guide agricultural interventions towards more balanced and diverse
nutritional outputs. New questions are raised that call for integration of agriculture,
ecology, nutrition, and socio-economic studies, particularly at the landscape scale.

38


23. Disseminating Agro forestry Innovations in Cameroon: Are
Relay Organizations Effective?
Degrande Ann1, Yeptiet Siohdjie Yannick2, Tsobeng Alain1, Asaah Ebenezer1 and
Takoutsing Bertin1

1
World Agroforestry Centre, ICRAF-West and Central Africa, Yaoundé, Cameroon;
2
University of Dschang, Faculty of Agronomy and Agricultural Sciences, Cameroon

Abstract

Ineffective dissemination methods have been partially responsible for low adoption
of agricultural innovations in Africa and consequently have failed to improve farmers’
livelihoods. Therefore, innovative and low cost ways of disseminating agricultural
innovations, especially farmer to farmer dissemination, are now gaining interest.
However, there is limited or conflicting evidence as to their effect on productivity
and poverty, as well as on financial sustainability. The present paper evaluates the
performance of relay organisations (community-based organisations that make the
bridge between research and farmers) in disseminating agroforestry innovations
in Cameroon and identifies factors that affect this performance. Overall, the 8 relay
organisations studied were successfully diffusing agroforestry innovations to
farmer groups. Though differences were not statistically significant, results suggest
that relay organisations which operate under favourable internal and external
factors perform best for most of the performance indicators. Also, the study puts
forward that external factors such as existing opportunities for agroforestry, strong
farmer associations and good road and communication networks, might affect the
effectiveness of relay organisations more than their internal capacity, reflected by
their human, material and financial resources. Further research involving more
relay organisations should focus on evaluating the sustainability and financial
viability of the approach and look at appropriate support mechanisms to enhance
relay organisations’ capacities to disseminate agroforestry innovations.

39


40


THEME 4: COMMUNICATING
COMPLEX KNOWLEDGE

41


42


24. Knowledge and technology transfer within an Evolving R4D
Framework in East Africa
Lynam, J

Independent Consultant, Nairobi Kenya

Abstract

The evolution of research themes and methods with the focus on sustainable
intensification of smallholder farming systems in the East African highlands are
moving well head of the state of the art in technology transfer methodologies and the
successful adoption of more knowledge intensive techniques by farmers. The paper
briefly reviews the methods inherent in research on production systems, particularly
within the context of the heterogeneity characterizing farming systems in the East
African highlands. The paper locates these with alternative trajectories for land
use intensification in the region. The current state of extension methods are then
reviewed in relation to the shift to more knowledge intensive techniques deployed
within a production systems framework. Given a increasing disparity between
research and extension approaches, the paper reviews more innovative approaches
to closing that gap. Finally, the paper analyzes our lack of understanding in the
steps from knowledge transfer to farmer learning to farmer change in management
practices with suggestions on how research on production systems must encompass
understanding how farmers change and adapt their farming system.

43


25. Walking the Impact Pathway: The CIALCA Experience in
Mobilising Agricultural Knowledge for the African Great Lakes
Region
Van Schagen Boudy1, Njukwe Emmanuel2, Katharina Paul Birthe3, Sengele Ndani4,
Mazibo Foma5, Blomme Guy6, Vanlauwe Bernard7, Van Asten Piet8.

1
Bioversity International, Bujumbura, Burundi; 2International Institute of Tropical
Agriculture, Bujumbura, Kampala; 3Wageningen University, Netherlands; 4Institut
de Recherche Agronomique et Zootechnique, Gitega, Burundi; 5Institut de Recherche
Agronomique et Zootechnique, Gitega, Burundi; 6Bioversity International, Kampala,
Uganda; 7Tropical Soil and Biology Institute of the International Center for Tropical
Agriculture, Nairobi, Kenya; 8International Institute of Tropical Agriculture, Uganda,
Kampala.

Abstract

An impact-oriented AR4D approach requires considerable investments in extension
and information capacity to ensure new agricultural technologies are adopted for
livelihood benefits. The Consortium for Improving Agriculture-based Livelihoods
in Central Africa (CIALCA) espouses a partner-oriented outreach strategy to
activate impact pathways for the scaling out of validated, science-based agricultural
information in ‘mandate areas’ in Burundi, Rwanda and the Democratic Republic
of Congo. The decentralized, geographically dispersed and multi-partner nature
of the Consortium poses unique challenges for effective knowledge flow and the
ability to deliver ‘knowledge into use’. The challenge is compounded by difficulties
in communicating complex technical solutions to farming communities with limited
adaptive capacity. Experience shows there is a strong need for extended facilitation
and follow-up by CIALCA extension specialists and trained partners to ensure
adequate understanding and adoption. Cascade training of partners can be effectively
supported through the provision of adequate resource materials such as factsheets,
video, and rural radio programming adapted for context, language and locality.
This paper will discuss the CIALCA knowledge-into-use praxis and elucidate some
of the challenges to and opportunities for agricultural science communication in this
context. We address the vital role of strong outreach partnerships, and how improved
partnership arrangements in a well-coordinated policy environment can reduce
the apparent trade-off between knowledge-intensive technologies and the ability
to reach scale. We further explore how the CIALCA Knowledge Resource Centre
operates as a knowledge broker and platform for the production and dissemination
of audience-specific resource materials. The current and potential role of ICT tools
for extension support, such as the CIALCA website, is discussed. Finally, this
paper reflects upon emerging opportunities for new, innovative approaches for the
repackaging and dissemination of scientific information, and options for ensuring
the long-term sustainability of CIALCA-generated knowledge.

44


26. Integrated Agricultural Research for Development (IAR4D)
an Approach to Enhance Small-holder Farmers’ Livelihood:
Experiences from Lake Kivu Region.
Buruchara, R.1, M. Tenywa2, J.G.M. Majaliwa2, W. Chiuri3, J. Mugabo4, S.O. Nyamwaro5,
Adewale A.6

1
CIAT (Centro Internacional de Agricultura Tropical)-AFRICA, Kampala, Uganda;
2
Makerere University, Faculty of Agriculture, Kampala, Uganda; 3CIAT (Centro In-
ternacional de Agricultura Tropical)/CIALCA, Kigali, Rwanda; 4Rwanda Agricultural
Board (RAB), Rwanda; 5Trypanosomiasis Research Centre, Kenya Agricultural Re-
search Institute, Kikuyu, Kenya; 6Merck Research Laboratories, North Wales, Pennsyl-
vania, United States

Abstract

Despite the resource endowment in the Lake Kivu region and research successes
registered in several projects implemented so far to improve food security,
income, and nutrition, poverty is yet to be significantly reduced. It is hypothesized
that the sectoral nature of conventional linear research approach in addressing
the interlinked productivity, natural resource management, market and policy
challenges / constraints in isolation is one of the most critical causes underlying
the agricultural under-performance. A new paradigm in agricultural research,
technology, innovation and knowledge system is required to break the paradox,
steer and accelerate the targeted development. Integrated Agricultural Research for
Development Approach (IAR4D) is a new approach that holds promise to reverse
the trend and enhance smallholder livelihood. The approach builds on previous
approaches such as Integrated Natural Resource Management; and addresses
productivity, market, natural resource management and policy and their interface
issues. This paper highlights key results in the “Proof of the IAR4D concept” and
its contribution to the small-holder farmers’ livelihood enhancement based on
Innovation Platforms (IPs) in the Lake Kivu Pilot Learning Site (LKPLS); one of
the three sites selected across Africa, to test this concept under the Sub-Saharan
Africa Challenge Programme. Strategic partnerships and 12 IPs were formed
and operationalised in the LK PLS. Farmers’ challenges and solutions to priority
issues were identified through facilitation and research. Linkages with research
institutions, NGOs and private sectors were established for value addition and
capacity building; while warrantee, credit and market links were done primarily to
sustain production and income. The operationalisation of the four elements of IAR4D
requires establishment of functional and strong linkages where farmers’ interests,
needs and/or opportunities are core to the participating stakeholders’ forum [an
innovation platform (IP)]. Farmers were motivated to produce, were involved in
crop diversification and value addition. It was observed that in situations where
productivity, market and NRM issues were addressed together, better IAR4D
results on small farmers’ livelihood were registered. Facilitation of IAR4D requires,
however, functional and efficient linkage and monitoring mechanism(s) akin to a
central processing unit to address emerging dynamic facilitation and research issues.

45


27. Communication channels used in dissemination of soil fertility
management practices in the Central Highlands of Kenya
Kimaru-Muchai S.W1, Mucheru-MunaM.W1, Mugwe J.M1, Mugendi D.N.1 and Mairura
F.S.2

1
Kenyatta University, Nairobi, Kenya; 2Tropical Soil and Biology Institute of the
International Center for Tropical Agriculture (CIAT-TSBF), Nairobi, Kenya

Abstract

Increased recognition of soil fertility depletion as the main biophysical factor
limiting crop production in many African small holder farms has renewed interest
in the dissemination of soil fertility management practices. Despite soil technology
development and research outputs, few of the recommendations from soil fertility
management research have been put into use by the target end users. The biggest
challenge to the accessibility and utilization of the existing knowledge lies with
the inadequacies in the communication methods and tools used in dissemination
and up scaling of soil fertility management practices. The objective of the study
was to investigate communication channels used in dissemination of soil fertility
management (SFM) practices inthe Central highlands of Kenya. Interview schedules
were used to collect information from 240 randomly selected farmers. Data was
analyzed using statistical package for social sciences (SPSS) programme. Results
showed that, other farmers were perceived as the most available and reliable source
of information. Demonstration and farmer to farmer extension methods were the
most preferred methods in dissemination of most of the SFM practices. Significant
positive relationship was found to exist between education and individual contact
approach (r=0.154, P=0.01, while farm size and gender positively correlated with
preference of group approach at (r=0.123, P=0.05) and (r=0.124, P=0.05), respectively.
Gender, education, farm size and number of times a farmer had been visited by an
extension agent were significant predictors in preference of field days in training of
animal manure. It was recommended that agricultural stakeholders should consider
farmers’ socio-economic factors in designing extension intervention strategies.

46


28. A global information and knowledge sharing approach to
facilitate the use of Musa genetic resources
Roux, N.1, Van den Bergh, I.1, Ruas, M.2 and Vezina, A.3

1
Bioversity International, Montpellier, France ; 2Department of Pharmacology, Univer-
sity of Oxford, Oxford, UK; 3Bedford Institute of Oceanography, Fisheries and Oceans
Canada, Dartmouth, NS, Canada

Abstract

Intraspecific crop diversification is a crucial component of any strategy to make
agricultural production systems more sustainable, and bananas/plantains are
no exception. Growing a mix of cultivars can contribute to safeguarding the crop
against pests and diseases, and make it more resilient in adverse environmental
conditions. In addition, different cultivars can bring different nutritional benefits
to poor populations, and offer a broader range of processing and marketing
opportunities. A comprehensive understanding of the existing Musa diversity, and
its potential uses, is therefore crucial, not only to genebank curators, molecular
biologists, breeders, phytopathologists and other Musa researchers, but also to
the rural households most dependent on the crop for their food and income.
Bioversity International is coordinating the implementation of the global Musa
genetic resources conservation and use strategy, and has recently launched the
global Musa genetic resources network, MusaNet. The network not only strives
to improve the conservation and safe dissemination of Musa genetic resources,
but it also seeks to fill the gaps in our knowledge of the Musa genepool through
increased characterization and multilocational evaluation efforts. The network will
invest further in the documentation of accessions held in genebanks and link the
Musa Germplasm Information System (MGIS) with global multi-crops systems
like Genesys. It will also soon be possible to order, through the MusaNet website,
clean in vitro Musa germplasm from the International Transit Centre (ITC), Belgium.
MusaNet will facilitate access to Musa genetic resources held at the regional level
and information about their characteristics through strong links with the Bioversity-
coordinated four regional Musa R4D networks. It is through these partnerships
that demonstration trials at the farm level, like those already existing in certain
Asian countries within the framework of National Repository, Multiplication and
Dissemination Centres (NRMDCs), will be set up. A recent study of the impact
of the ITC showed that strengthening germplasm evaluation will allow a greater
focus on users’ needs. Farmers’ experiences on traits of popular cultivars, and other
cultivar-level information, will be summarized in the online banana compendium
on the ProMusa website. This paper discusses these global partnerships and this
networking approach for reaching farmers with information about Musa genetic
resources.

47


29. Targeting farmer’s priorities for effective agricultural
intensification in the humid highlands of eastern Africa
Mowo Jeremias1, Tanui Joseph1, Masuki Kenneth2 and Mukuralinda Athanase3

1
World Agroforestry Centre (ICRAF), Nairobi, Kenya; 2Mlingano Agricultural Re-
search Institute, Tanga, Tanzania; 3World Agroforestry Center (ICRAF), Rwanda

Abstract

Experience by the African Highlands Initiative in Eastern Africa has shown that
failure to attract farmer’s interest in most proven natural resource management
technologies is mainly due to lack of approaches that tackles the interrelated factors
responsible for poor resource management and most importantly failure to consider
the priorities of the farmers hence leading to loss of interest in the introduced
technologies. Ranking of farmers constraints in agricultural production has often
come up with priorities that are contrary to the aims of the agricultural research
and development organizations. Constraints like poor soil fertility and soil erosion
are mainly ranked low compared to issues like water, financial capital, and energy.
The later are not necessarily under the mandate of research and development
organizations yet, without addressing them it is difficult to attract farmer’s interest
in the introduced technologies. Using integrated approaches, it was a hypothesized
that that addressing a high-priority constraint such as domestic water availability or
energy as part of an integrated catchment management approach leads to multiple
system benefits and greater local commitment to natural resource management. This
hypothesis was tested in the humid highlands of Tanzania, Ethiopia and Uganda
using action research. Results showed that when farmers’ priorities are given due
consideration, their interest in managing land and water resources increase leading
to multiple benefits including improvement in soil conservation, and increased
water recharge and agricultural productivity.

48


30. Reintroducing Vicia faba beans in resource-poor farming systems
– adoption of a participatory farmer-led initiative
Karltun Erik1, Gichamo Tesfanesh2, Chiwona-Karltun Linley3, Lemenih Mulugeta4 and
Tolera Motuma4

1
Swedish University of Agricultural Sciences, Department of Forest Soils, Uppsala,
Sweden; 2Swedish University of Agricultural Sciences, Department of Urban and Ru-
ral Department, Uppsala, Sweden; 3Division for International Health Care Research,
Department of Public Health, Karolinska Institute, Stockholm, Sweden; 4 Wondo Genet
College Forestry and Natural Resources, Shashamane, Ethiopia

Abstract

The theft of fresh bean pods from the field has been identified as one of the major
reason for farmers abandoning the cultivation of beans in the Beseku-Ilala peasant
association, Ethiopia. To avoid conflicts over theft accusations, and to preserve
human security and community integrity farmers simply stopped cultivating beans.
The abandonment led to (i) a negative impact on household nutrition and health,
(ii) deterioration in household economy, (iii) conflicts in households between wives
and husbands and (iv) negative consequences on soil fertility since the beans was the
only nitrogen fixing legume in the crop rotation. Iterative discussions with farmers
came up with the suggestion that one of the traditional institutions in the village,
Idir, could formulate local by-laws to control bean theft. Within a space of one year
we observed farmers growing bean in some of the villages and not in some. Two
of the villages Shibeshi Gasha 1 and Shibeshi Gasha 2 had not reintroduced bean
cultivation while the third village, Boye had successfully reintroduced beans. This led
us to ask; Why had two of the villages adjacent to the one that had reintroduced bean
cultivation not done so? The results revealed that where the village Idirs comprised
of men bean cultivation was reintroduced. Farming households that could afford to
rent farmland away from their village were also starting to grow beans. Households
headed by women and households where the man was the one who attended the
village meeting did not grow beans. Upon closer investigation and probing, it was
revealed that the men in those households did not share the information with their
women or wives, for fear of continued theft despite the formulation of by-laws.
Information from focus group discussions on attitudes towards and perceptions
of theft identified a range of feelings and interpretations. The over-riding feeling
was that it was difficult to control bean theft because security and legal means to
do so were very rudimentary. In addition, the mix of different socio-cultural and
socio-economic conditions provided an environment that was rife with conflict.
Further research is required to acquire a deeper understanding of these issues and
the challenges of scaling-up bean cultivation in rural Ethiopia.

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POSTER SESSIONS

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THEME 1: SYSTEM
COMPONENTS

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