Evans School Policy Analysis & Research Group (EPAR)

Studies of improved seed adoption in developing countries almost always draw from household surveys and are premised on the assumption that farmers are able to self-report their use of improved seed varieties. However, recent studies suggest that farmers’ reports of the seed varieties planted, or even whether seed is local or improved, are sometimes inconsistent with the results of DNA fingerprinting of farmers' crops. We use household survey data from Tanzania to test the alignment between farmer-reported and DNA-identified maize seed types planted in fields. In the sample, 70% of maize seed observations are correctly reported as local or improved, while 16% are type I errors (falsely reported as improved) and 14% are type II errors (falsely reported as local). Type I errors are more likely to have been sourced from other farmers, rather than formal channels. An analysis of input use, including seed, fertilizer, and labor allocations, reveals that farmers tend to treat improved maize differently, depending on whether they correctly perceive it as improved. This suggests that errors in farmers' seed type awareness may translate into suboptimal management practices. In econometric analysis, the measured yield benefit of improved seed use is smaller in magnitude with a DNA-derived categorization, as compared with farmer reports. The greatest yield benefit is with correctly identified improved seed. This indicates that investments in farmers' access to information, seed labeling, and seed system oversight are needed to complement investments in seed variety development.

This brief presents an overview of EPAR’s previous research on nutrition and food security and outlines summaries and key findings from 15 technical reports and research briefs. Key findings are drawn from our own original analyses as well as from other sources, which are cited in the individual reports. We also include appendices briefly summarizing EPAR’s research on health and climate change, topics somewhat related to nutrition and food security, and EPAR’s confidential work on nutrition and food security.

This four-part analysis describes the current suite of food security measures, then analyzes the respective relationships between food security and poverty, GDP, and crop yields using findings from in-depth literature reviews. Food security measures are criticized for inaccurately characterizing food security at individual, household, and national scales, yet guidelines exist to prescribe a food security measure for a given situation. Some authors see the potential of a combination of indicators that apply at different scales rather than a single, universal food security measure. Limited literature exists on the relationship between food security and poverty, GDP, or crop yields. The relationship between food security and poverty is particularly challenging because neither term has a consistent definition, and the limited literature suggests a lack of consensus among experts. Little empirical research exists on the relationship between food security and GDP, though studies generally note an association between the two Studies that evaluate food security and crop yields provide limited evidence that the two are associated, though many studies use measures of crop yield as food security indicators and vice versa. More research is needed to establish whether there are preferred food security measurement tools for specific scales and situations, and to further explore the relationship between food security and poverty, GDP, and crop yields.

This is "Section G" of a report that presents estimates and summary statistics from the 2008/2009 wave of the Tanzania National Panel Survey (TZNPS), part of the Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA). We present our analyses of data related to consumption of priority foods, total value of consumption, levels of food consumption and production, including analyses by zone in Tanzania. We find, for example, that the mean total value of household consumption was higher for agricultural households (US$27.28) compared to non-agricultural households (US$26.59), but the mean per capita value of household consumption was higher for non-agricultural households (US$7.32) compared to agricultural households (US$5.24). The mean per capita value of weekly consumption for the Southern zone was only US$5.34, compared to the highest mean per capita value of US$6.63 in the Eastern zone. The Central zone still had the lowest per capita value of consumption at US$4.40.