Research Topics

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 #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 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.