Research Topics

EPAR Research Brief #228
Publication Date: 04/18/2014
Type: Literature Review
Abstract

Cassava (Manihot esculenta Crantz) is a widely-grown staple food in the tropical and subtropical regions of Africa, Asia, and Latin America. In this brief we examine the environmental constraints to, and impacts of, smallholder cassava production systems in Sub-Saharan Africa (SSA) and South Asia (SA), noting where the analysis applies to only one of these regions. We highlight crop-environment interactions at three stages of the cassava value chain: pre-production (e.g., land clearing), production (e.g., soil, water, and input use), and post-production (e.g., crop storage). At each stage we emphasize environmental constraints on production (poor soil quality, water scarcity, crop pests, etc.) and also environmental impacts of crop production (e.g., soil erosion, water depletion and pesticide contamination). We then highlight good practices for overcoming environmental constraints and minimizing environmental impacts in smallholder cassava production systems. Evidence on environmental issues in smallholder cassava production is relatively thin, and unevenly distributed across regions. The literature on cassava in South Asian smallholder systems is limited, reflecting a crop of secondary importance (though it is widely found elsewhere in Asia such as South East Asia), in comparison to cassava in much of SSA. The majority of the research summarized in this brief is from SSA. The last row of Table 1 summarizes good practices currently identified in the literature. However, the appropriate strategy in a given situation will vary widely based on contextual factors, such as local environmental conditions, market access, cultural preferences, production practices and the policy environment.

EPAR Technical Report #254
Publication Date: 03/20/2014
Type: Literature Review
Abstract

This overview introduces a series of EPAR briefs in the Agriculture-Environment Series that examine crop-environment interactions for a range of crops in smallholder food production systems in Sub-Saharan Africa (SSA) and South Asia (SA). The briefs cover the following important food crops in those regions; rice (#208), maize (#218), sorghum/millets (#213), sweet potato/yam (#225), and cassava (#228).

Drawing on the academic literature and the field expertise of crop scientists, these briefs highlight crop-environment interactions at three stages of the crop value chain: pre-production (e.g., land clearing and tilling), production (such as water, nutrient and other input use), and post-production (e.g., waste disposal and crop storage). At each stage we emphasize environmental constraints on crop yields (including poor soils, water scarcity, crop pests) and impacts of crop production on the environment (such as soil erosion, water depletion and pest resistance). We then highlight best practices from the literature and from expert experience for minimizing negative environmental impacts in smallholder crop production systems.

This overview (along with the accompanying detailed crop briefs) seeks to provide a framework for stimulating across-crop discussions and informed debates on the full range of crop-environment interactions in agricultural development initiatives.

A paper based on this research series was published in Food Security in August 2015.

EPAR Technical Report #115
Publication Date: 12/14/2010
Type: Literature Review
Abstract

As part of the Crops & Climate Change series, this brief is presented in three parts: 1) An evaluation of the importance of Sorghum and Millet in SSA, based on production, net exports, and caloric need, 2) A novel analysis of historical and projected climate conditions in Sorghum and Millet growing regions, followed by a summary of the agronomic and physiological vulnerability of Sorghum and Millet crops, 3) A summary of current resources dedicated to sorghum and millet, based on research and development investments and National Adaptation Programmes of Action. Our analysis indicates that sorghum and millets may become increasingly important in those areas of SSA predicted to become hotter and subject to more variable precipitation as a result of climate change. Although sorghum and millet are currently grown on marginal agricultural lands and consumed for subsistence by poorer population segments, climate change could render these drought- and heat-tolerant crops the most viable future cereal production option in some areas where other cereals are currently grown. Fewer international development resources are currently devoted to sorghum and millet than are devoted to other cereal grains, and current resource allocation may not reflect the increased reliance on these grains necessitated by projected climactic changes.

EPAR Technical Report #114
Publication Date: 12/14/2010
Type: Literature Review
Abstract

As part of the Crops & Climate Change series, this brief is presented in three parts: 1) An evaluation of the importance of wheat in SSA, based on production, net exports, and caloric need, 2) A novel analysis of historical and projected climate conditions in wheat-growing regions, followed by a summary of the agronomic and physiological vulnerability of wheat crops, 3) A summary of current resources dedicated to wheat, based on research and development investments and National Adaptation Programmes of Action. Overall, this analysis indicates that the importance of wheat as an imported product remains high throughout SSA, though food crop production and dependence is concentrated in a relatively small area. Wheat-growing regions throughout SSA are likely to face yield decreases as a result of predicted rises in temperatures and possible changes in precipitation. Resources intended to aid adaptation to climate change flow primarily from public sector research and development efforts, though country-level adaptation strategies have not prioritized wheat.

EPAR Presentation #103
Publication Date: 11/08/2010
Type: Literature Review
Abstract

This presentation reviews and presents definitions and theories around incorporating sustainability into agricultural productivity. We review ecological, social, and economic sustainability and examine agricultural productivity through the lenses of nutrition, gender, environment, and climate change. The annotated bibliography identifies critical work from academic literature to aid in defining sustainable agricultural productivity. The methodology to generate these reports included searching the University of Washington Libraries system, Google Scholar, the University of Minnesota’s AgEcon Search, as well as the websites of the FAO, World Bank, and CGIAR. We also reviewed the most recent (2010) publications of the Handbook of Agricultural Economics and the Handbook of Development Economics. 

EPAR Technical Report #106
Publication Date: 11/02/2010
Type: Literature Review
Abstract

How development organizations, NGOs, and governments can best allocate scarce resources to those in need has long been debated. As opposed to universal allocation of resources, a more targeted approach attempts to minimize program costs while maximizing benefits among those with the greatest need or market opportunity. Drawing on literature from several sectors,this brief presents two categories of beneficiary targeting in the development context: administrative targeting and self-targeting. The paper includes a brief overview of targeting and segmentation in development, a summary of reasons for targeting, theoretical and practical critiques of targeting, and a discussion of targeting methods in research and practice, including examples from the literature. Implementation examples cited in this body of research include food aid program targeting by self-reported household income in Egypt; fertilizer use in low-potential zones of Uganda; and seven strategic initiatives to improve drought and disease resistance in crops in Asia and Sub-Saharan Africa.  We find that beneficiary segmentation has several theoretical advantages.  Improved targeting may increase the efficiency and equity of organizational and program efforts and help better match interventions to recipient preferences, increasing the likelihood of adoption and participation. Development organizations may improve the focus of both their strategic priorities and budgets through customized targeting methods. However, concerns exist regarding the accuracy, reliability, cost, and time-constraints of targeting methodologies. Creating valid and reliable target groups with implementation potential remains a significant challenge. 

EPAR Technical Report #62
Publication Date: 10/23/2010
Type: Literature Review
Abstract

Researchers expect that agriculture in Sub-Saharan Africa (SSA) will experience major impacts from climate change, leaving the already food-insecure region subject to the largest contractions of agricultural incomes and food availability. As part of the Crops & Climate Change series, this brief presents an evaluation of the importance of maize in SSA, a novel analysis of historical and projected climate conditions in maize-growing regions, and a summary of current resources dedicated to maize adaptation. Overall, this analysis indicates that the importance of maize as a food crop remains high throughout SSA. Significant portions of maize-growing SSA will face climate conditions outside the range of country- and continent-level historical precedent. Rising temperatures and changes in precipitation are predicted, and reductions in maize yield and production will likely follow. Resources intended to aid adaptation to climate change flow primarily from public sector research and development efforts. Country-level adaptation strategies are often hampered by lack of funding and insufficient institutional capacity. Strategies for adaptation include improved agricultural practices and technology as well as infrastructure and program investments to absorb the impacts of climate change.

EPAR Technical Report #71
Publication Date: 10/22/2010
Type: Literature Review
Abstract

Agriculture in Sub-Saharan Africa is expected to experience major impacts from climate change, leaving the already food-insecure region subject to the largest contractions of agricultural incomes and food availability. As part of the Crops & Climate Change series, this brief presents an evaluation of the importance of rice in SSA, a novel analysis of historical and projected climate conditions in rice-growing regions in relation to rice's agronomic requirements, and a summary of current resources dedicated to rice. This three-pillared approach serves to identify gaps in resources dedicated to rice productivity in SSA in light of the crop’s resilience to projected changes in climate and increasing importance in the region’s food security. Overall, this analysis indicates that the importance of rice in SSA is increasing even as climate change is projected to have significant effects on the temperature in rice-growing regions. The current resources dedicated to rice research and dissemination of improved methods are insufficient to meet Africa’s rice production needs, and may not reflect the importance of the crop for the region’s food security under the future projected climate.

EPAR Technical Report #98
Publication Date: 10/12/2010
Type: Literature Review
Abstract

Cereals and pulses are important food and cash crops for farmers and rural households in Ethiopia. Despite the economic and food security importance of these crops, data and opinion suggest a yield gap: actual smallholder farm yields do not achieve estimated potential yields for wheat, sorghum, maize, lentils and peas. Furthermore, cereal prices in Ethiopia fall between import and export parity prices, limiting their international trading prospects. Although there are significant wheat imports, these reflect the influx of food aid, rather than competitive trade on the international market. The purpose of this brief is to estimate yield gaps in important Ethiopian crops in order to identify potential areas for productivity gains. We find that wheat, sorghum and maize all exhibit the potential for yield gains to increase domestic food availability. Additionally, all three crops experienced significant spikes in yield in the 2006 season. Further investigation into the climate conditions and policy in place that year may generate potential strategies to increase future yields. Analysis of Ethiopian lentil and pea yields suggest that productivity gains may be possible to increase food availability. Limited access to improved technologies appears to be the main constraint to pulse productivity in Ethiopia. Opportunities to increase lentil and pea yields appear to exist through increasing cultivation of improved varieties.

EPAR Technical Report #100
Publication Date: 09/28/2010
Type: Literature Review
Abstract

Without availability and access to a variety of foods, populations in the developing world are suffering from deficiencies in iron, zinc, iodine, vitamin A, and other micronutrients in addition to deficiencies in energy and protein. Supplementation and fortification programs have demonstrated effectiveness, but there is an increasing interest in potentially more sustainable solutions via agricultural interventions. The review examines the literature regarding agricultural interventions and pathways to diet diversification and whether desired nutritional outcomes are achieved.  We find a strong sentiment that agricultural interventions can improve dietary diversity, and that dietary diversity can improve nutrition and related health outcomes. The programs with demonstrated ability to improve nutrition outcomes are most often cross-cutting interventions, borrowing from the agriculture, nutrition, and public health traditions. While these multi-platform programs can be costly to evaluate and difficult to implement, the evidence supports their potential to create sustainable quality-of-life improvements in target regions. The pathways by which agricultural interventions achieve impact are not fully clear, however. The greatest knowledge gaps are directly related to the lack of integration between program design and evaluation. Many evaluations are based on small sample sizes, lack control groups or baseline data, are subject to selection bias, or face other challenges to rigorous statistical analysis.