Dataset

EPAR Technical Report #303
How Common Crop Yield Measures Misrepresent Productivity Among Smallholder Farmers
Publication Date: 08/10/2015
Type: Data Analysis
Abstract

Common estimates of agricultural productivity rely upon crude measures of crop yield, typically defined as the weight harvested of a crop divided by the area harvested. But this common yield measure poorly reflects performance among farm systems combining multiple crops in one area (e.g., intercropping), and also ignores the possibility that farmers might lose crop area between planting and harvest (e.g., partial crop failure). Drawing on detailed plot-level data from Tanzania’s National Panel Survey, our research contrasts measures of smallholder productivity using production per hectare harvested and production per hectare planted.

An initial analysis (Research Brief - Rice Productivity Measurement) looking at rice production finds that yield by area planted differs significantly from yield by area harvested, particularly for smaller farms and female-headed households. OLS regression further reveals different demographic and management-related drivers of variability in yield gains – and thus different implications for policy and development interventions – depending on the yield measurement used. Findings suggest a need to better specify “yield” to more effectively guide agricultural development efforts.

 

Research Brief - Data for Policy Discussion Paper, 2016 Presentation Slides - Data for Policy, 2015 Presentation Slides - ICAE, Research Brief - Rice Productivity Measurement
EPAR Research Brief #312
Realized Yield Gains From Quality Seed and Improved Varieties
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.

Research Brief, Results Coding Spreadsheet
EPAR Technical Report #298
Cassava Bacterial Blight and Postharvest Deterioration
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. 

Full Report, Results Coding
EPAR Technical Report #46
Zambian Maize Price and Production Analysis
Publication Date: 09/03/2009
Type: Literature Review
Abstract

This literature review provides information on the dynamics of the maize market and maize prices in Zambia. We address four key topics: average production costs and breakeven prices for maize farmers in Zambia, main drivers of volatility of maize production volumes, key factors driving the differences between Zambian and global maize prices, and policies that may have contributed to increased farmer productivity. 

Literature Review
EPAR Research Brief #44
The Challenges and Opportunities Associated with Bt Maize in Sub-Saharan Africa
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.

Literature Review
EPAR Technical Report #28
Storage, Transportation and Aggregation of Agricultural Products for Smallholder Farmers in Sub-Saharan Africa
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.

Literature Review