Issue 9, October 2012

Increasing productivity with ISFM
Climate-smart systems
Soil: nature’s Pandora’s box
Bridging yield gap
Best practices in maize
ISFM for bananas
NRM in cassava and yam
Boosting productivity of cassava
Cocoa and REDD
CRPs and NRM
Commercial products for farmers

Download PDF

Back to stay


“The soil nutrient losses in sub-Saharan Africa are an environmental, social, and political time bomb. Unless we wake up soon and reverse these disastrous trends, the future viability of African food systems will indeed be imperiled.”
– Dr Norman Borlaug, 14 March 2003, Muscle Shoals, Alabama, USA

IITA was the first major African link in the integrated network of international agricultural research centers. It was also one of the first centers that engaged in  farming systems research. In the 1980s and 1990s, the Institute had a very strong program on natural resource management (NRM), covering aspects of soil fertility management, cropping system diversification, and improved agronomy. This, along with the emphasis on the genetic improvement of the major food crops in the humid tropics, provided an integrated program of research on sustainable agricultural development.

Over the past fifteen years, the focus of research-for-development activities at IITA shifted away from NRM, party driven by changes in the investment portfolios of important donors. With the area of soils and natural resources back on top of the development agenda and recognizing that the potential of improved germplasm can only be realized in the presence of appropriate crop and nutrient management practices, IITA has recently decided to increase its investments on NRM research for development with a particular focus on soils.

The March 2012 issue of R4D Review commemorated IITA’s 45 years. It focused on the successes, challenges, and prospects of the genetic improvement programs; these are key to the Institute’s success in improving food crop production in sub-Saharan Africa. Innovations in genetic improvement have shown how enhanced crop productivity, along with other ingredients, such as capacity building and policies, has helped to lift millions out of poverty.

This second issue for the year highlights our important work undertaken in partnership with national and international institutions in the area of sustainable NRM in sub-Saharan Africa. It also signals IITA’s renewed focus on this area of research. The articles cover the three main pillars of the NRM research-for-development agenda: (1) Integrated Soil Fertility Management, aiming at enhancing crop productivity following agroecological principles, with a livelihood focus, (2) Sustainable Land Management, aiming at rehabilitating soils for the provision of other essential ecosystem services, with a landscape focus, and (3) Climate Change, aiming at enhancing the resilience of farming systems to climate variability.

Climate-smart perennial systems

Banana-coffee systems in East Africa. Photo by P. van Asten
Banana-coffee systems in East Africa. Photo by P. van Asten

Laurence Jassogne,, Piet van Asten, Peter Laderach, Alessandro Craparo, Ibrahim Wanyama, Anaclet Nibasumba, and Charles Bielders

Coffee is a major cash crop in the East African highland farming systems. It represents a high proportion of export values at the national level (for example >20% for Uganda). It is also crucial for the sustainability of the livelihoods of smallholder farmers.

During a survey in Uganda, smallholder farmers explained that the income generated by coffee had sent their children to school and helped to build permanent houses. Prices of coffee have also been increasing in the past decennia, motivating them to continue growing the crop.

Although coffee is a promising cash crop, smallholder farmers that grow coffee are still vulnerable. Soil fertility is declining, pest and disease pressure is increasing, populations are rising, and land is continuously fragmented. Above all, climate change is starting to take its toll and puts further pressure on the coffee-based farming systems—directly, because temperature and rainfall have an impact on the physiology of Arabica coffee, and indirectly because the incidence and severity of certain pests and diseases such as the coffee berry borer and coffee leaf rust will increase.

Figure 1. Change of suitability for Arabica-growing areas in Uganda using MAXENT approach and based on a ‘business as usual’ climate change scenario.
Figure 1. Change of suitability for Arabica-growing areas in Uganda using MAXENT approach and based on a ‘business as usual’ climate change scenario.

Current and future suitability of coffee growing areas
In collaboration with Dr Peter Laderach (CIAT), the direct effect of climate change on the suitability of coffee-growing areas in Uganda was mapped (Fig. 1).

If the current coffee crop systems do not change (i.e., same coffee varieties and management practices), these areas will move up the slope and the suitable surface area will decrease. In this light, climate-smart coffee- based systems need to be developed to sustain the existing coffee- based systems.

Adaptation strategies in coffee systems
IITA-led field surveys in the region, combined with a literature review, revealed that there is a multitude of coffee systems that exist. This diversity reflects the variability among farmers in terms of their resource availability, objectives, political history, and opportunities (Fig. 2).

Highest yields can be obtained in systems without shade or with low shade levels (Fig. 2). However, these same systems represent higher production risks and a higher use of external inputs. In polyculture systems and forest systems, on the other hand, highest yield quality can be obtained with the minimum use of external inputs. Furthermore, they allow, among others, a better adaptation to climate change, higher carbon stocks, and more ecological services. Quantifying these trade-offs and raising awareness among farmers and other stakeholders along the coffee value chain will help informed and sustainable decisions to be made about the coffee systems.

Figure 2. Trade-offs at a farmer-plot level in coffee systems.
Figure 2. Trade-offs at a farmer-plot level in coffee systems.

The more coffee is shaded, the more it is protected from rising temperatures and extreme weather events. Shade in coffee systems can reduce the average temperature in the lower coffee canopy by a few degrees. Although shade is an interesting technology to make coffee systems “climate smart” and hence, adapted to climate change, it is not the primary reason why farmers add shade to their coffee. Shade plants often produce fruit and/or timber. This diversifies the income of the farmer.

The same happens when farmers intercrop coffee with banana. Adding banana to the system increases food security, diversifies income, and adds shading to coffee. A country-wide survey in Uganda showed that coffee/banana intercropping was a common cropping system except in North and North-West Uganda. The incidence of coffee leaf rust was 50% when coffee was intercropped with banana.

Most farmers have some shade trees in their coffee; many practice intercropping with common beans. The combination of short- and long-term benefits of such shade systems makes them ideal climate-smart candidates. Shade trees also sequester carbon, contributing to the mitigation of the effects of climate change. In the end, few farmers (<5%) have pure full-sun monocropped coffee.

Figure 3. Pie charts depict major nutrient deficiencies based on soil and foliar samples of 10 coffee farms per site (black dots).
Figure 3. Pie charts depict major nutrient deficiencies based on soil and foliar samples of 10 coffee farms per site (black dots).

Constraints in diversified systems
However, shade trees also compete with coffee for light, nutrients, and water. If this competition is not managed well, then the shaded coffee system risks collapse, especially in conditions of poor soil fertility. Due to increasing population pressure and land fragmentation, integrated soil fertility management (ISFM) will help to manage nutrient competition. In a shaded system, the turn-over of biomass contributes to nutrient recycling. Organic matter from shade trees or banana will act as in-situ mulch. However, soils in Uganda are poor and have some major nutrient deficiencies (Fig. 3).

Replenishing soil fertility by adding external inputs is necessary if farming systems need to be sustained. Adding small amounts of fertilizers adapted to site-specific deficiencies increases fertilizer use efficiency and forms part of the ISFM approach. Coffee can be a major driver for the adoption of fertilizers by smallholders since farmers are generally organized for access to output markets. The same organizational lines can then be used to provide access to input markets.

Understanding the farmers’ objectives, perceptions, and constraints is critical in identifying the adoption pathways of production-increasing technologies. To continue this research, IITA will start a case study in Rakai (Uganda) at a site of the CGIAR Research Program on Climate Change, Agriculture, and Food Security (CCAFS). Here, climate-smart coffee scenarios will be developed in a participatory manner with smallholder farmers, based on data from previous projects, interviews with individual farmers and groups, and farm measurements. Greenhouse gas emissions will be quantified to measure the mitigation potential of the existing coffee systems. Furthermore, fertilizer trials throughout Uganda will be set up to test the site-specific recommendations. IITA also plans to further advance its collaborative research efforts on modeling trade-offs and synergies in coffee smallholder systems in East Africa.

Cocoa and REDD

James Gockowski,, Valentina Robiglio, Sander Muilerman, Nana Fredua Agyeman, and Richard Asare

Smallholder farmers produce improved cocoa planting materials, Côte d'Ivoire. Photo by IITA
Smallholder farmers produce improved cocoa planting materials, Côte d'Ivoire. Photo by IITA

In the humid lowlands of Africa, the expansion of extensive low-input agriculture is the most important driver of tropical deforestation and forest degradation with a negative impact on biodiversity and climate change (Norris et al. 2010; Phalan et al. 2011).

A recent global analysis of the climate change impact of agriculture estimated that between 8.64 and 15.1 million square km of land were spared from the plow as a result of yield gains achieved since 1961 (Burney et al. 2010). These land savings generated avoided greenhouse gas (GHG) emissions representing between 18% and 34% of the total 478 GtC emitted by humans between 1850 and 2005. A similar land use change analysis conducted for West Africa estimated that over 21,000 km2 of deforestation/forest degradation that occurred between 1988 and 2007 could have been avoided if the improved seeds/fertilizer already developed in the 1960s had been adopted (Gockowski and Sonwa 2011).

A methodology for quantifying and qualifying the impact of agricultural intensification on deforestation and poverty has been developed. This is based upon (a) the remote sensing analysis of land use change, (b) structured interviews with a random sample of rural households, and (c) an anthropological case study, all conducted in a defined benchmark area. The 1201 square km benchmark in the Bia district, Ghana, is the most important cocoa-growing area in the country whose increasingly diminished forests are home to the endangered Roloway monkey and are a global conservation priority. Cocoa producers in this benchmark have experienced rapid yield gains as a result of a sequential series of intensification policies that began in 2003.

Figure 1. Land-use change trajectories, 2000-2011.
Figure 1. Land-use change trajectories, 2000-2011.

Measuring deforestation and land use intensification
The retrospective household survey chronicled the land-use and migration history of each household in establishing a mean rate of deforestation from 1960 to 2003. More recent estimates were determined from the interpretation of satellite imagery from 2003 Landsat, 2006 Spot, and 2011 ALOS. Based on these analyses, the mean average rate of deforestation has fallen from 1,006 ha/year prior to the initiation of intensification policies to 212 ha/year.

Most of the deforestation still occurring has entailed encroachments in the Bia Game Reserve and the Krokosua Hills Forest Reserve and, to a lesser degree, Bia National Park whose environs are more stringently protected (Fig. 1). Outside these reserves there is scarcely any forest remaining.

The intensification policies initiated in the early 2000s focused on the acquisition and distribution of subsidized fertilizers and pesticides to farmers. The impact of these policies on yields and incomes was evaluated by comparing predicted outputs at 2000 and 2011 levels of input use with a micro-econometric model of household cocoa production constructed with data from the household survey (Table 1). Yields in the benchmark nearly tripled mainly because of the increased use of fertilizers and household income doubled (Gockowski et al. 2011).

Table 1. A comparison of mean input use in 2000-01 prior to fertilizer interventions and in 2010-11.
Table 1. A comparison of mean input use in 2000-01 prior to fertilizer interventions and in 2010-11.

Supporting smallholder fertilizer use instead of forests through REDD
The objective of Reducing Emissions from Deforestation and Forest Degradation (REDD) is to reduce GHG. The method is designed to use market valuation and financial incentives to reward deforestation agents, such as the cocoa farmers of Ghana, for a reduction in emissions.

To produce the output achieved in the benchmark area of our study using the extensive cocoa technology of 10 years ago would require an additional 150,000 ha of rainforest. The amount and value of carbon not entering our atmosphere because of avoided deforestation are an external value that is not captured in the market price received by the farmers intensifying production. Consequently there will be a socially suboptimal level of investment in intensification. REDD is envisaged as a mechanism for addressing this market failure.

Fertilizer use in Africa is the lowest of any region in the world. Not only does this perpetuate poverty it also contributes to emissions of GHG and loss of biodiversity. We have developed a methodology for determining the amount of deforestation avoided through increased use of fertilizer. Thus, it is a relatively simple matter to value the emissions that are also avoided. More difficult is the question of how to distribute these resources so as to correct this perceived market failure. Directly paying farmers for environmental services has proven to be a costly endeavor and has rarely been successful with smallholders.

Cocoa plants and pods, Ghana. Photo by IITA
Cocoa plants and pods, Ghana. Photo by IITA

As an alternative we propose a government-to-government transfer of earmarked funds for supporting agricultural intensification through investments in improved public infrastructure, extension services, agricultural research, and, yes, fertilizer subsidies. There is a risk that more productive technologies lead to greater deforestation, at least at the local level. To address this, a portion of the REDD funds should be used to enforce protected forest boundaries from encroachment. When properly implemented, agricultural intensification can relieve poverty, conserve biodiversity, and reduce emissions of GHG.

Burney, J.A., S.J. Davis, and D.B. Lobell. 2010. Greenhouse gas mitigation by agricultural intensification. Proceedings of the National Academy of Sciences 107(26): 12052–12057.
Gockowski, J. and D. Sonwa. 2011. Cocoa Intensification Scenarios and their Predicted Impact on CO2 Emissions, Biodiversity Conservation, and Rural Livelihoods in the Guinea Rain Forest of West Africa. Environmental Management 48(2): 307–321.
Gockowski, J., V. Robiglio, S. Muilerman, and N.F. Agyeman. 2011. Agricultural Intensification as a Strategy for Climate Mitigation in Ghana: An evaluative study of the COCOBOD High Tech Program, rural incomes, and forest resources in the Bia (Juaboso) District of Ghana. Final report to CGIAR Challenge Program on Climate Change, Agriculture and Food Security (CCAFS)—Poverty Alleviation through Climate Change Mitigation.
Norris K., A. Asase, B. Collen, J. Gockowski, J. Mason, B. Phalan, and A. Wade. 2010. Biodiversity in a forest-agricultural mosaic—the changing face of West African rainforests. Biological Conservation 143: 2341–2350.
Phalan, B, M. Onial, A. Balmford, and R. Green. 2011. Reconciling Food Production and Biodiversity Conservation: Land Sharing and Land Sparing Compared. Science 333: 1289.

From traditional to science based: Transforming agricultural practices

In recent times discussions on deforestation in the tropics more often than not have pointed to agricultural expansion as one major factor behind the depletion of forests.

Forests are crucial to life on earth: IITA forest. Photo by IITA.
Forests are crucial to life on earth: IITA forest. Photo by IITA.

This argument has been underpinned by the fact that agricultural growth in the region has been driven by area expansion rather than improved productivity.

Environmentalists say the depletion of forests hurts biodiversity, encourages climate change, and jeopardizes our future existence on this planet.

But a new study finds that increasing agricultural productivity through the application of fertilizers will reduce the rate of deforestation and help transform agriculture with less damage to the environment.

The study by researchers Jim Gockowski of IITA and D. Sonwa of CIFOR, two centers of the CGIAR, established that the boom in production in the last two decades in the major cocoa-producing countries of Côte d’Ivoire, Ghana, Nigeria, and Cameroon was detrimental to the forest, as farmers had to clear large expanses of trees for cocoa cultivation.

Cocoa production, they say, doubled between 1987 and 2007 but at a heavy cost, as West Africa’s Guinean Rainforest (GRF)—a region described as the ‘global biodiversity hotspot’—shrank to 113,000 km2.

The principal driver of this environmental change has been the expansion of low-input smallholder agriculture that depends on environmentally destructive practices, such as slash-and-burn and land clearing.

The researchers found that increasing the use of fertilizer on cocoa–timber farms would have spared about 2 million ha of tropical forest from being cleared or severely degraded.

Cocoa farmer drying beans. Photo by IITA.
Cocoa farmer drying beans. Photo by IITA.

The study suggested that farmers could have achieved the same outputs without widespread deforestation through the intensified use of fertilizers and agrochemicals coupled with improved crop husbandry.

By doing so farmers would have doubled their incomes and helped to avoid deforestation and degradation. This would have generated a value of over US$1,600 million on 1.3 billion tons of CO2 emissions that would not have come as a result of the deforestation.

The findings should be taken into consideration in discussions about efforts to reduce emissions from deforestation and degradation (REDD), say the researchers. Instead of considering complicated strategies involving monetary or in-kind transfers to farmers or communities for altering their land- use behavior, funds to support REDD could be used to provide incentives and promote agricultural intensification efforts that would lead to higher rural incomes, greater food security, and avoid emissions through the achievement of higher agricultural yields.

The limited use of fertilizer in the GRF (less than 4 kg/ha of total nutrients) may have been logical in 1960, when West African populations were only 25% of today’s levels and forest land was still relatively abundant. That choice is no longer tenable in a context where only 15 to 20% of the GRF remain. There are no longer any frontier forests in West Africa for future generations to exploit.

Strategies to reduce deforestation and conserve biodiversity in West Africa must thus focus on transforming agricultural practices from the traditional to modern science-based methods. Fertilizers- for-Forest (F4F) technology is available to sustainably intensify production and has achieved impressive increases in cocoa yield on a limited scale in parts of the GRF.

The authors say that REDD funding support to mitigate climate change as discussed in the Copenhagen Accord offers the potential of significant new public resources for investments in agricultural research and extension and market infrastructure to support the transformation of traditional agriculture in West Africa. The estimated value of the CO2 emissions thus avoided is conservatively estimated at $565/ha for achieving the envisaged doubling of yields. A significant proportion of REDD+ funding should be used to increase the adoption and level of fertilizer use in an F4F program.

Issue 6, March 2011

Climate change and plant health
Healthy banana TC industry
Safe exchange of germplasm
Germ-free germplasm
In Kanti Rawal’s footsteps
Restoring the IITA forest
Investing in aflasafeâ„¢
Sustainable production and distribution of clean banana
Developing clean seed systems
Clean yam tubers
Hot bath for the suckers!
Transgenic banana for Africa

Download PDF

Related website

Aflatoxin management website –

Climate change & plant health

Irmgard Hoeschle-Zeledon*, or
*Coordinator of the CGIAR Systemwide Program on Integrated Pest Management (SP-IPM) convened by IITA

Diverse crop production system. Photo by IITA.
Diverse crop production system. Photo by IITA.

The discussion on the impact of climate change (CC) on agriculture has often focused on how changes in temperature, rainfall, and CO2 concentrations will affect the suitability of temperate regions for crop production and how crops will react in terms of yields. The effects of climate change on biotic factors in the tropics, such as weeds, pests, and pathogens (hereafter referred to as pests), have not received much attention.

Empirical data exist, however, to show that these biotic factors have major effects in determining productivity in the tropics. For instance, during the 1997 El Niño phenomenon, the mean temperature on the Peruvian coast increased by about 5 °C above the annual average, causing a decrease in potato infestation by the leafminer fly Liriomyza hydobrensis, which otherwise was a major pest. However, the abundance and infestation severity of all other pests increased in all crops, including potato (Kroschel et al. 2010). The complex consequences of CC particularly on pests and pathogens are still only imperfectly understood (Gregory et al. 2009).

CGIAR’s work on climate change
What are IITA and the other centers of the Consultative Group on International Agricultural Research (CGIAR) doing to mitigate the impacts and adapt to the effects of CC on pests? Historically, CGIAR centers have a broad R4D focus; centers have been developing knowledge (e.g., pest profiles), products (e.g., new crop varieties, biocontrol agents against invasive pests), and technologies (e.g., predictive models, diagnostic tools) that are suitable for diverse agroecologies including the tropics, wet, humid, semiarid, and dry, and to some extent the temperate zones as well. The broad knowledge and experience of centers provide an unprecedented advantage to assess the products and technologies in different agroecologies and weather settings and to determine their resilience and ability to cope in altered climatic situations.

Several programs directly focus on managing pests. For instance, the breeding of crop varieties for resistance to pests and pathogens has always been a focus of the CGIAR. With the uncertainties of CC, this work has become more relevant. Breeding for resistance to drought and waterlogging, although not the primary objectives, also aim at making varieties better able to tolerate biotic threats, since drought and excess water in the soil both increase the plants’ vulnerability to these factors.

A good example is the effort to develop drought-resistant maize cultivars by CIMMYT and IITA. These will not only allow the expansion of maize production into areas with less reliable rainfalls but also ensure the continued production in regions that are prone to future water scarcity. Drought- tolerant cultivars also reduce the risk of aflatoxin contamination in the field. Additional characters are incorporated into the drought-tolerant maize, such as resistance to maize streak disease which is endemic in Africa. Similar programs are ongoing to develop drought-resilient cassava and cowpea, and yam with tolerance for major pests.

The CGIAR centers are also working towards the development of cropping systems with greater intra- and interspecific diversity to increase resilience to CC-induced threats from biotic factors. For example, IITA is promoting maize–cowpea intercropping to reduce the pest pressure on cowpea.

Bioversity International is exploring how intra-specific crop genetic diversity on-farm not only reduces current crop losses to pests and pathogens, but also decreases the risk of genetic vulnerability and the potential of future crop damage, thus enhancing the impact of other IPM strategies and providing farmers with increased adaptive capacity to buffer against climatic changes.

CIP developed a temperature-driven phenology model for the potato tuber moth, Phthorimaea operculella that provides good predictions for the population in areas where the pest exists at present (Kroschel et al. 2010). Linked with geographic information systems (GIS) and atmospheric temperature, the model allows the simulation of risk indices on a worldwide scale to predict future changes in the distribution of the species due to increasing temperatures. The approach can also be used for other insect species. Hence, CIP created the Insect Life Cycle Modeling software (ILCYM) to facilitate the development of other insect phenology models. With its support, the phenology model can be implemented and allows for spatial simulation of insect activities.

Many centers support the collection and conservation of plant genetic diversity that can be built into new cultivars to enhance their resistance to biotic stresses. Diagnostics capacity is continuously augmented for the accurate and timely recognition of endemic pests, new variants, and invasive pests. Crop biodiversity—landraces and wild relatives that are the reservoirs of genes for abiotic and biotic factors—is conserved ex situ to protect the species from erosion by CC-induced changes.

In a collaborative effort, CIP, IITA, icipe, and partners in Germany and Africa are implementing a project to understand the effects of rising temperatures on the distribution and severity of major insect pests on main food crops. ILCYM will be further improved and adapted to cover a wide range of insect species. The results will contribute to filling the knowledge gap about CC effects on economically important insect herbivores and their natural enemies.

IITA is planning to research the effect of changes in temperature on the invasion potential of major biotic threats in the Great Lakes region of East Africa and elsewhere: Banana bunchy top virus (BBTV), Banana Xanthomonas Wilt (BXW), and Panama Disease–Tropical Race 4, cassava brown streak virus disease, cassava mosaic disease, maize streak, soybean rust, and pod borer pests, among others.

As whiteflies and aphids are considered to become more problematic with increased temperatures, IITA is also preparing research on the biocontrol of different whitefly and aphid species in vegetables and staple crops.

A project has been proposed on the bio-enhancement of seeds and seedlings of cereals and vegetables for East Africa to stimulate the plants’ defense mechanisms against pests and pathogens expected to increase in number, frequency, and severity. This project also addresses the registration of biopesticides and the availability of endophytes to the tissue culture industry.

CGIAR research programs
Under the new CGIAR Research Programs (CRPs), centers are addressing CC-induced crop health issues in various ways. Breeding for resistance to predicted biotic stresses continues to be a major focus in CRP3 (roots, tubers, banana) and its subcomponents. This component, coordinated by CIP, specifically recognizes CC and agricultural intensification as drivers for higher pressure from pests. Hence, this program aims at developing management strategies for priority biotic threats to these crops. These include the development of improved detection and monitoring tools, and surveillance methods for detecting and mapping existing, emerging, and resurgent molecular pests and pathogens. It will look into increasing general plant and root health through the enhancement of the natural disease suppressing potential of soils, and the antagonistic pest and disease potential of the aboveground agroecosystems.

The CRP on Integrated Systems for the Humid Tropics, led by IITA, will have a substantial focus on CC, its impact on pests, and plans for mitigation. For example, research will establish the relationship between CC and key cassava pests to develop integrated pest management (IPM) strategies including those for whitefly, African root and tuber scale, termite, green mite, aphid, and mealybug.

Phenology models for insect and mite pests and their antagonists on several crops will be developed and validated and their potential for changes in warming will be determined.

In collaboration with CABI, community surveillance for pests and diseases will take place through the expansion of the mobile plant clinic network.

Larva of the noctuid moth feeding on the pistil of cowpea. Photo by S. Muranaka, IITA.
Larva of the noctuid moth feeding on the pistil of cowpea. Photo by S. Muranaka, IITA.

Knowledge and decision support tools for the management of potato and sweetpotato pests (diseases and insects) will be developed and assessed in relation to the expected intensification of the agroecosystems in the humid and subhumid tropics.

Sustainable management of cassava virus disease in the cassava-based system will also be studied, and the vulnerabilities of these systems to CC- induced pest and disease problems will be determined.

The CIAT-coordinated CRP on CC, Agriculture, and Food Security began operations this year. It will continue the activities initiated by the CGIAR Challenge Program on CC. This CRP aims at mainstreaming strategies that address the management of CC- induced pest and disease threats among international and national agencies. It will identify and test innovations that enable communities to better manage and adapt to climate-related risks from biotic factors.

A lot of surprise shifts in ecosystems could come. It is therefore important that research capacity and knowledge bases are maintained to understand and rapidly react to mitigate any debilitating impacts (Shaw and Osborne 2011).

To accomplish this, it is necessary to establish good baseline data on current pest status in agroecosystems. This knowledge base will serve as a reference point to measure the fluctuations and the effectiveness of interventions.

It is important to determine the key weather variables that could change as a consequence of CC and their influence on agroecosystems and pests, and establish preemptive coping strategies. Available CC models could be handy for predicting CC factors.

A diverse scientific base including specialists in pathology, entomology, ecology, taxonomy, and epidemiology is required. They should work together to ensure that the outcomes of their research are linked to existing knowledge, economic forces, and common understanding (Shaw and Osborne 2011).

As it generally takes more than 10 years to breed a new resistant cultivar of a crop, breeding programs must start well in advance of the serious risk of a biotic threat Breeders need to be informed on the problems which might become important in the future (Chakraborty et al. 1998 in Juroszek and Tiedemann 2011).

Crops being bred for abiotic threats such as drought, waterlogging, and salinity should be prepared for the pests that could flourish under these conditions and select varieties that can tolerate pests as well.

Changes in occurrence, prevalence, and severity of infections and infestations will also affect crop health management (CHM) practices. There is a need to effectively disseminate and use those techniques that are currently underused (Juroszek and Tiedemann 2011).

Significant contributions could be made in improved field monitoring of pests and diseases, and better delivery systems for pest control products (Strand 2000 in Juroszek and Tiedemann 2011). Preventive crop protection measures may become more relevant under CC to reduce the risks (Juroszek and Tiedemann 2011).

CC is a global problem that affects all countries. Hence, global cooperation is required. However, given the nature of plant pests and pathogens, more local or regional strategies need to be put in place that define potential risks and measures to tackle expected threats. Investments in early detection systems, including border controls to monitor the migration of pests through plants, plant products, and other goods, will be the key to avoid the spread of invasive pests and reduce high management and eradication costs (FAO).

New farming practices, different crops, and IPM technologies must be developed to control the established pests and prevent the spread of new ones (FAO).
Governments should consider developing country-specific strategies to cope with CC-induced changes and put in place favorable policies for the introduction and promotion of new technologies for CHM.

It is also crucial to create and augment awareness about the effects of CC among policymakers and other officials involved in developing agricultural strategies.

Chakraborty S and Newton AC. 2011. Plant Pathology 60: 2-14.

FAO. unknown.

Govindasamy B et al. 2003. Climate Dynamics 21: 391-404.

Gregory PJ et al. 2009. Journal of Experimental Botany 60: 2827-2838.

Juroszek P and von Tiedemann A. 2011. Plant Pathology 60: 100-112.

Kroschel J et al. 2010.

Shaw MW and Osborne TM. 2011. Plant Pathology 60: 31-43.

Climate change is everyone’s responsibility

Climate change (CC) is a long-term change in the statistical distribution of global weather patterns over periods of time that range from decades to millions of years. Several factors, known as climate forcers, usually natural events such as volcanic eruptions, earthquakes, solar radiation, and ocean currents shape climate change.

Life on earth is a dynamic process and intimately connected to the biotic forms in cohabitation, farmin systems, and the environment. A shift in one parameter alters the delicate balance in an interconnected world. Source: L. Kumar, IITA.
Life on earth is a dynamic process and intimately connected to the biotic forms in cohabitation, farmin systems, and the environment. A shift in one parameter alters the delicate balance in an interconnected world. Source: L. Kumar, IITA.

However, the climate forcer of the 21st century CC—carbon dioxide (CO2)—is mainly human-induced and attributed to the burning of fossil fuels and tropical deforestation. The property of CO2 to trap heat within the earth’s atmosphere is contributing to global warming. Thus, a rise in CO2 levels increases the warming effect. Trapped heat in the atmosphere warms oceans, melts ice caps, raises sea levels, and increases average surface temperature, all of which are affecting normal weather patterns.

Some of the abnormal changes experienced over the last two decades include severe and prolonged droughts, extreme storms and prolonged rainfall pattern, high temperatures, and heat waves. These sudden and extreme variations in weather patterns due to ‘global warming’ have profound effects on living organisms on earth. The altered conditions create risks as well as opportunities favoring certain living beings over others and contribute to shifts in niches. In addition, it could lead to long-term variations in climate (e.g., permanent increase in average temperature) that might irreversibly affect biodiversity in a given region.

In the context of agriculture, sudden and abnormal changes in weather could change the suitability of a given environment for cultivation of crops. This could be due to abiotic factors such as drought, heat (cold), or excessive water directly linked to weather or simply due to increased pests and diseases that would severely impede performance of the crops. Since crops, diseases (pathogens), and pests (including vectors) are intimately associated and influenced by the environment, any shift in these factors will alter the balance, and could have a positive impact (e.g., decreased pest pressure) or negative impact (e.g., increased pest pressure) on overall crop performance.

Using simulation models, attempts the world over are being made to determine the impact of CC on agroecosystems to establish appropriate coping strategies, particularly for the negative impacts. Although this appears simple, it is the most complex issue confronting researchers, policymakers, governments, and entrepreneurs worldwide.

Communities are working together to bridge the gaps and establish global coordination networks to mitigate the impact of CC. IITA and other CGIAR centers, together with national and international organizations, are contributing to these endeavors with a primary focus on conserving biodiversity and improving the resilience of smallholder agriculture in the developing countries in Africa, Asia, and Latin America.

Jim Gockowski: Sustainable intensification of agriculture

Jim Gockowski
Jim Gockowski

Jim Gockowski is an agricultural economist with the Sustainable Tree Crops Program (STCP) based in IITA-Ghana.

About 15 years ago, the Rockefeller Science Foundation offered Jim the opportunity to work in any five of CGIAR centers. His wife’s passion for Africa and Cameroon in particular made the family to choose IITA. In this interview with Atser Godwin, Gockowski shares his experience as he works in Africa for Africa.

Tell us about your work.
When I first started with IITA in 1995, I was involved in the Alternative to Slash and Burn Program. This was a system-wide program looking at issues of deforestation along the forest margins and trying to come up with alternatives to extensive agriculture that uses the forest as an input in the production system. Also, beginning in 2000, we got involved with STCP, which is a public-private partnership between the global chocolate industry and USAID that is focused on the cocoa belt of West Africa and is working on sustainable improvement of livelihoods of cocoa- producing households.

What has been its impact?
We do lots of evaluation, and we try and do some policy work with our studies and findings.

The impact of the social sciences in the STCP and the Alternative to Slash and Burn Program has been on two levels: One is on policy levels that is providing information and evidence, and the impact of policies or in some cases the lack of policies on livelihoods, outcomes, and the environment.

The other impact is in helping to transfer developed products—basically knowledge on natural resources management—to farmers. We have done this through development of curriculums for farmers’ field schools. We are also involved with some of the climate negotiations around the Reducing Emissions from Deforestation and Forest Degradation (REDD) initiative.

What have been the impacts of STCP?
We have trained over 120,000 farmers in five countries of West Africa. We have also worked with farmer organizations to strengthen their efforts through collective marketing with probably over 40,000 households being affected. These are probably two major impacts with the STCP. Farmers from the field school training have seen returns increased by between 40 and 43%.

What is REDD all about?
REDD is a means of reducing carbon emissions into the atmosphere. It was a coalition of rainforest countries that got together in 2007 at the conference of the parties of the Kyoto protocol. They put their REDD agenda on the negotiating table in terms of the climate negotiation. The basic concept is that as developing countries, they need to provide jobs for their people and one way that is historical is to convert the rainforest into production agriculture or other forms of earning livelihoods.

The REDD idea is the concept of economic compensation to countries with tropical rainforests for their foregone opportunities of not deforesting the rainforest.

IITA-STCP works with partners to improve the livelihoods of households in cocoa-based production systems in West Africa. Photo by S. David, IITA.
IITA-STCP works with partners to improve the livelihoods of households in cocoa-based production systems in West Africa. Photo by S. David, IITA.

What is the IITA project called Fertilizers-for-Forest (F4F)?
What we know in West and Central Africa is that agriculture is the principal driving force for deforestation and in particular the practice of slash and burn. When this happens, you get wood ash that is loaded with potassium and some trace amounts of nitrogen. The wood ash improves the soil but it is not a sustainable practice.

The idea of Fertilizers-for-Forest is really about sustainable intensification led by policy changes that would offer farmers an alternative to cutting down the forest and burning to get wood ash. The alternative is that instead of cutting the forest to get the biomass, let’s use fertilizers.

We believe that this type of intensification is necessary for preserving what is being left of the West African forest which is 18% of what it used to be. It is also one way that we can conserve the Congo basin rainforest.

How do you see IITA playing a role in mitigating the effects of climate change?
There are two ways that we can play a role. One is to support policy-led intensification projects by working with NARES partners and better soil fertility management options. This will take away pressure on the rainforest and help in reducing global warming. This is on the mitigation side. Again, we know that climate is getting warmer, with predictions that in the next 70 years, temperatures could rise by more than three degrees. We also know that agricultural productivity doesn’t respond positively to warmer temperatures hence there will be a reduction in yields. So we need to be focused on the climate response of our major production systems as it proceeds. It will be a gradual thing but we need to be strategic about it. We need to strategize.

On the adaptation side, we need to be working on drought-tolerant crops. We need to do adaptive research that would allow the African smallholder farmers to deal with a change in climate.

Another area is that of institutions. We have problems with our credit markets, crop insurance, and input markets. We need to strengthen these institutions and a government policy that favors the private sector approach that doesn’t distort markets.

What are some of the positive changes that you are seeing in Africa?
From a rural perspective, I have seen a lot of self-empowerment. I think this is happening because democracy is playing its role by giving the rural majority a voice and that voice is starting to be heard. Again, I don’t think it will be business as usual because the population is growing quite fast and we need to feed these teeming millions. We need to modernize agriculture and African farmers are beginning to demand those from their public servants.

What makes your work successful?
If I have made any success, it is due to diligence. If you work hard, I guess good things result. We have a wonderful institute with a lot of good scientists and all that I can say is that I have been fortunate to work with very good scientists.