Research Topics

EPAR Technical Report #354
Publication Date: 11/29/2018
Type: Research Brief
Abstract

Precise agricultural statistics are necessary to track productivity and design sound agricultural policies. Yet, in settings where intercropping is prevalent, even crop yield can be challenging to measure. In a systematic survey of the literature on crop yield in low-income settings, we find that scholars specify how they estimate the yield denominator in under 10% of cases. Using household survey data from Tanzania, we consider four alternative methods of allocating land area on plots that contain multiple crops, and explore the implications of this measurement decision for analyses of maize and rice yield. We find that 64% of cultivated plots contain more than one crop, and average yield estimates vary with different methods of calculating area planted. This pattern is more pronounced for maize, which is more likely than rice to share a plot with other crops. The choice among area methods influences which of these two staple crops is found to be more calorie-productive per ha, as well as the extent to which fertilizer is expected to be profitable for maize production. Given that construction decisions can influence the results of analysis, we conclude that the literature would benefit from greater clarity regarding how yield is measured across studies.

EPAR Technical Report #310
Publication Date: 11/20/2015
Type: Literature Review
Abstract

Cereal yield variability is influenced by initial conditions such as suitability of the farming system for cereal cultivation, current production quantities and yields, and zone-specific potential yields limited by water availability. However, exogenous factors such as national policies, climate, and international market conditions also impact farm-level yields directly or provide incentives or disincentives for farmers to intensify production. We conduct a selective literature review of policy-related drivers of maize yields in Ethiopia, Kenya, Malawi, Rwanda, Tanzania, and Uganda and pair the findings with FAOSTAT data on yield and productivity. This report presents our cumulative findings along with contextual evidence of the hypothesized drivers behind maize yield trends over the past 20 years for the focus countries.

EPAR Technical Report #311
Publication Date: 08/06/2015
Type: Literature Review
Abstract

This report provides a summary of findings from six Financial Inclusion Insights (FII) data analysis reports conducted by various agencies for the Bill & Melinda Gates Foundation (BMGF). These reports investigate barriers to financial inclusion and use of digital financial services (DFS) in Bangladesh, India, Kenya, Nigeria, Pakistan, Tanzania, and Uganda. We compile comparable gender-specific statistics, summarize the authors’ findings to determine commonalities and differences across countries, and highlight gender-specific conclusions and recommendations provided in the studies. 

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 Results Coding #138
Publication Date: 05/12/2011
Type: Literature Review
Abstract

This presentation summarizes the biotic (insects, viruses, fungi, bacteria, weeds, and post-harvest pests) and abiotic (drought and soil nutrients) stresses that may be addressed or countered in order to improve crop yield in Sub-Saharan Africa and South Asia. Data is sourced from FAOSTAT, GAEZ, a series of academic papers by Waddington & Dixon, and IMPACT model estimates. Slides compare area harvested, yield, and yield gap percentage with total calories per year, the 2005 value of production, and projected growth between 2005-2030. 

EPAR Technical Report #134
Publication Date: 04/10/2011
Type: Literature Review
Abstract

Agriculture is a principal source of livelihood for the Tanzanian population. Agriculture provides more than two-thirds of employment and almost half of Tanzania‘s GDP. Women play an essential role in agricultural production. The sector is characterized as female-intensive, meaning that women comprise a majority of the labor force in agriculture (54%). This brief reviews the academic and grey literature on gender and agriculture in Tanzania, providing an overview on the structure of households, the household structure of agricultural production, information on women’s crops, and gender and land rights in Tanzania. We conclude with a summary of challenges to women in agriculture, and of potential implications for women of advancements in production technology and other economic opportunities at the household level. 

EPAR Research Brief #144
Publication Date: 04/06/2011
Type: Research Brief
Abstract

This research brief synthesizes evidence on the effects of policy incentives on agricultural productivity. The evidence discussed is primarily drawn from documents provided to EPAR by the Bill and Melinda Gates Foundation. We review the role of policy and institutions in the Asian Green Revolution, a detailed case study on how policy changes have removed smallholder productivity constraints and contributed to growth, and the theory on the connection of policy incentives to productivity growth. 

EPAR Research Brief #137
Publication Date: 03/30/2011
Type: Research Brief
Abstract

This brief presents selected material from the Fourth African Agricultural Markets Program (AAMP) policy symposium, Agricultural Risks Management in Africa: Taking Stock of What Has and Hasn’t Worked, organized by the Alliance for Commodity Trade in Eastern and Southern Africa and the Common Market for Eastern and Southern Africa that took place in Lilongwe, Malawi, September 6-10, 2010.  We draw almost exclusively from Rashid and Jayne’s summary, “Risk Management in African Agriculture: A review of experiences.”  This article summarizes across the background papers, with major findings grouped into three broad categories: cross cutting, government-led policies, and modern instruments.

EPAR Technical Report #118
Publication Date: 03/16/2011
Type: Literature Review
Abstract

This report combines analyses from four previous EPAR briefs on the effects of climate change on maize, rice, wheat, sorghum, and millet production in Sub-Saharan Africa (SSA). In addition, this brief presents new analysis of the projected impact of climate changes in SSA. We include comparisons of the importance of each crop, of their vulnerability to climate change, and of the research and policy resources dedicated to each. Especially with respect to climatic susceptibility, these rankings provide a comparative summary based upon the analysis conducted in the four previous EPAR briefs, statistical analyses of historical yield and climate data, and future climate model predictions. According to the indicators analyzed, our research suggests that maize leads the cereal crops in terms of importance within SSA and in terms of research and policy attention. Our analysis of climate conditions and the crop’s physical requirements suggests that many maize-growing areas are likely to move outside the range of ideal temperature and precipitation conditions for maize production. Rice is the third most important crop in terms of consumption dependency, fourth in terms of production, but second only to maize in terms of research funding and FTEs. Sorghum and millet rank second and third in production importance and second and fifth in consumption importance, but rank below maize and rice in terms of FTE researchers. Their role is complicated by the fact that they are often considered inferior goods; SSA consumers often substitute away from sorghum and millet consumption if they are able to do so. Wheat is the least-produced crop of the five, and the second to last in terms of consumption importance. However, it still ranks above millet in terms of FTE researchers.