Research Topics

EPAR RESEARCH BRIEF #386
Publication Date: 05/08/2019
Type: Research Brief
Abstract

In many countries in Sub-Saharan Africa and South Asia smallholder farmers are among the most vulnerable to climatic changes, and the observed shocks and stresses associated with these changes impact agricultural systems in many ways. This research brief offers findings on observed or measured changes in precipitation, temperature or both, on five biophysical pathways and systems including variable or changing growing seasons, extreme events, biotic stressors, plant species density, richness and range, impacts to streamflow, and impacts on crop yield. These findings are the result of a review of relevant documents cited in Kilroy (2015), references included in the IPCC draft Special Report on Food Security, and targeted searches from 2015 - present for South Asia and Sub-Saharan Africa. 

EPAR Technical Report #307
Publication Date: 09/30/2015
Type: Literature Review
Abstract

This report reviews and summarizes the existing evidence on the impact of access to financial services/products on measures of production, income and wealth, consumption and food security, and resilience for smallholder farmers  and other rural customers and their households in Sub-Saharan Africa. This study covers four main types of financial products/services: 1) credit; 2) savings; 3) insurance; 4) transactional products. We also review the very limited evidence on the effectiveness of bundling these products/services together and of combining them with other offerings such as trainings or support for access to markets, and of providing them via digital channels. We note when financial products/services have been specifically designed to serve the needs of rural customers or smallholder farmers, since the needs of these groups are often very different from those of other stakeholders.

EPAR Research Brief #312
Publication Date: 07/30/2015
Type: Literature Review
Abstract

This brief reviews the evidence of realized yield gains by smallholder farmers attributable to the use of high-quality seed and/or improved seed varieties. Our analysis suggests that in most cases, use of improved varieties and/or quality seed is associated with modest yield increases.  In the sample of 395 trials reviewed, positive yield changes accompanied the use of improved variety or quality seed, on average, in 10 out of 12 crops, with rice and cassava as the two exceptions.

EPAR Technical Report #298
Publication Date: 03/23/2015
Type: Literature Review
Abstract

Cassava production is prone to many constraints throughout the production cycle, including biotic, abiotic, and management constraints. This brief reviews the literature on the production impacts of two key cassava stressors: cassava bacterial blight (CBB) and postharvest physiological deterioration (PPD). We summarize available estimates of the frequency and magnitude of these constraints relative to other drivers of cassava production losses that affect smallholder farmers in Sub-Saharan Africa (SSA), review the control strategies proposed in the literature, report on the views of several experts in the field, and identify research gaps where relatively little appears to be known about CBB or PPD yield impacts or best practices for CBB or PPD management. 

EPAR Technical Report #94
Publication Date: 08/17/2010
Type: Literature Review
Abstract

Market-oriented agricultural production can be a mechanism to increase smallholder farmer welfare, rural market performance, and contribute to overall economic growth. Cash crop production can allow households to increase their income by producing output with higher returns to land and labor and using the income generated from sales to purchase goods for consumption. However, in the face of missing and underperforming markets, African smallholder households are often unable to produce efficiently or obtain staple foods reliably and cheaply. This literature review summarizes the available literature on the impact of smallholder participation in cash crop and export markets on household welfare and rural markets. The review focuses exclusively on evidence from Sub-Saharan Africa regarding top and emerging export crops, with the addition of tobacco and horticulture due to the volume of research relevant to smallholder welfare gains from the production of these crops. It includes theoretical frameworks, case studies, empirical evidence, and historical analysis from 42 primary empirical studies and 112 resources overall.

EPAR Technical Report #60
Publication Date: 03/05/2010
Type: Literature Review
Abstract

In recent years, product supply chains for agricultural goods have become increasingly globalized. As a result, greater numbers of smallholder farmers in South Asia (SA) and Sub-Saharan Africa (SSA) participate in global supply chains, many of them through contract farming (CF). CF is an arrangement between a farmer and a processing or marketing firm for the production and supply of agricultural products, often at predetermined prices. This literature review finds empirical evidence that demonstrates that the economic and social benefits of CF for smallholder farmers are mixed. A number of studies suggest that CF may improve farmer productivity, reduce production risk and transaction costs, and increase farmer incomes. However, critics caution that CF may undermine farmers’ relative bargaining power and increase health, environmental, and financial risk through exposure to monopsonistic markets, weak contract environments, and unfamiliar agricultural technologies. There is consensus across the literature that CF has the best outcomes for farmers when farmers have more bargaining power to negotiate the terms of the contract. In reviewing the literature on CF, we find a number of challenges to comparing studies and evaluating outcomes across contracts. This literature review summarizes empirical findings and analyses regarding contract models and best practices to increase farmers’ bargaining power and decrease contract default.

EPAR Research Brief #50
Publication Date: 12/29/2009
Type: Research Brief
Abstract

EPAR’s Political Economy of Fertilizer Policy series provides a history of government intervention in the fertilizer markets of eight Sub-Saharan African countries: Côte d’Ivoire, Ghana, Kenya, Malawi, Mozambique, Nigeria, Senegal, and Tanzania. The briefs focus on details of present and past voucher programs, input subsidies, tariffs in the fertilizer sector, and the political context of these policies. The briefs illustrate these policies’ effect on key domestic crops and focus on the strengths and weaknesses of current market structure. Fertilizer policy in SSA has been extremely dynamic over the last fifty years, swinging from enormous levels of intervention in the 1960s and 70s to liberalization of markets of the 1980s and 1990s. More recently, intervention has become more moderate, focusing on “market smart” subsidies and support. This executive summary highlights key findings and common themes from the series.

EPAR Research Brief #44
Publication Date: 08/17/2009
Type: Literature Review
Abstract

Bt maize technology involves developing hybrid maize crops that incorporate genes from the soil-dwelling bacteria Bacillus thuringiensis (Bt). The primary benefit of Bt maize technology is the heightened crop protection from stem borers, which are maize pests that can inflict serious crop losses. Bt maize has been cultivated in Mexico, South Africa and several countries in the European Union, with limited cultivation in Sub-Saharan Africa (SSA). This report provides a summary of literature on the potential benefits and challenges associated with Bt maize production in SSA. Research studies of Bt maize in the Philippines and South Africa are also briefly reviewed. There is little peer-reviewed literature available, with evidence challenging the assumed benefits of Bt maize for smallholder farmers in SSA. As a result, we also review research briefs and conference proceedings available from reputable international organizations. Although some of the available literature references the ethical concerns over Bt maize production, we focus on searching for science-based discussions related to any potential biodiversity, biosafety, or socio-economic impacts of Bt maize technology for smallholder farmers in SSA.

EPAR Technical Report #28
Publication Date: 08/10/2009
Type: Literature Review
Abstract

Smallholder farmers in Africa are largely located in poor rural areas, are often geographically dispersed, and have limited access to road and communication infrastructure, thus raising the cost of market participation. This is especially true for farmers growing relatively low value staple crops. This literature review summarizes research on the challenges and innovations in linking smallholder producers of staple grains to markets in Sub-Saharan Africa, with a focus on post-harvest issues including storage, aggregation, and transportation. For each post-harvest stage, we describe challenges faced by farmers and current efforts to address these challenges. In our review, we find a large amount of literature on the constraints to smallholder production and marketing but relatively few examples of innovative or novel technologies designed to improve storage and transportation for rural smallholder producers in Africa. Existing technologies have often been available for some time but have not seen widespread adoption, apparently due to high costs or inadequate funding for on-farm testing and extension. We conclude that the literature is somewhat divided as to whether interventions linking smallholder farmers to markets should be entirely market-driven and focus on linkages that can be profitable without subsidization, or whether NGO- and donor-driven interventions should play a role.

EPAR Technical Report #34
Publication Date: 05/03/2009
Type: Literature Review
Abstract

Lack of nitrogen (N) is often cited as the most limiting factor in agriculture. Although N composes nearly 80% of the atmosphere, plants are unable to use this form of the element (N2) because of the strong triple bonds between the two atoms. Nitrogen deficiency is especially problematic in the soils of Sub-Saharan Africa (SSA). Low levels of N and other soil fertility problems have severe poverty, malnutrition and environmental degradation consequences for SSA. The process by which atmospheric N2 is converted into N compounds that can be used by living things is called nitrogen fixation. Biological nitrogen fixation (BNF or biofixation) offers an alternative or additional means to traditional nitrogen fixation to increase plant-available nitrogen. Through a symbiotic relationship, an N-fixing bacterium infects a plant (usually a legume) and forms nodules on the roots of the plant in which N fixation occurs. This literature review examines the expansion and benefits of BNF, the constraints to BNF adoption, BNF regulations, and success stories of developing and distributing BNF technologies worldwide. BNF technology can be an efficient and effective tool for decreasing environmental degradation and increasing soil fertility, yields, income, and food security in SSA, although many constraints to farmer adoption exist.