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researcher spotlight

Lilia Bliznashka

Lily Bliznashka is a Research Fellow in the Nutrition, Diets, and Health Unit. Her research focuses on assessing the effectiveness of multi-input nutrition-sensitive and nutrition-specific interventions and the mechanisms through which they work to improve maternal and child health and nutrition globally. She has worked in Burkina Faso, Burundi, Tanzania, and Uganda.

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Innovation Policy and Scaling

Thomas Assefa

Associate Research Fellow

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Bio

Thomas Woldu Assefa is an Associate Research Fellow in the Innovation Policy and Scaling Unit. He is a development economist whose research interests include agricultural technology adoption, rural development, agricultural transformation, behavioral economics, agricultural extension and advisory services, food and nutrition security, and survey methods and measurements. Most of his research involves experimental and quasi-experimental impact evaluation methods, and he has extensive experience in designing and implementing large-scale household surveys and randomized controlled trials. In his recent work, Thomas has focused on understanding smallholder farmers’ fertilizer adoption decisions and innovative methods to minimize measurement errors in development economics research.

Before joining IFPRI, he worked as a postdoctoral research fellow at the University of Georgia, as a consultant for the World Bank and the Food and Agriculture Organization of the United Nations (FAO), and as an IMMANA postdoctoral research fellow in a program administered by Tufts University. Thomas received his MSc from the Norwegian University of Life Sciences and holds a PhD from the University of Georgia, US.

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Publications

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Journal Article

Evaluating large-scale government investments in fertilizer adoption: The Ethiopian experience

2026Assefa, Thomas; McCullough, Ellen; Berhane, Guush
Details

Evaluating large-scale government investments in fertilizer adoption: The Ethiopian experience

We evaluate the impact of a large Government of Ethiopia intervention to raise fertilizer supply by establishing five fertilizer blending facilities supplying fertilizers tailored to local soil nutrient profiles. We rely on the phased geographic rollout of blending facility establishment to identify the causal effect on fertilizer use, application rates, crop yields, gross crop revenue, and household consumption. Combining effects of multiple treatment periods, each estimated using a doubly robust difference-in-difference model, we find that the blending facilities increased the probability that farmers adopt the new blended fertilizers by 22 percentage points and increased application rates by 17 kg/ha (baseline adoption was zero). The facilities mostly induced farmers who previously used DAP to switch to NPS, and we find large decreases in DAP adoption (by 22 percentage points, 47% of the control group base mean) and application rates (16 kg/ha, 52% of the control group base mean) yet no impact on overall fertilizer adoption or application rates. Though the new blended fertilizers were expected to perform better, there is no evidence they improved crop yields, crop gross revenue, or household consumption. The effect of the intervention was more pronounced (with larger increases in NPS use and larger decreases in DAP use) for farms located near demonstration plots, which the Government used to train farmers about the agronomic response to the new fertilizers. We confirm results using three large-scale longitudinal datasets and show that they are robust to choices of specification, treatment definition, and inference assumptions. JEL classification: O12, O13, Q16, Q18

Year published

2026

Authors

Assefa, Thomas; McCullough, Ellen; Berhane, Guush

Citation

Assefa, Thomas; McCullough, Ellen; and Berhane, Guush. 2026. Evaluating large-scale government investments in fertilizer adoption: The Ethiopian experience. American Journal of Agricultural Economics 108(3): 874-900. https://doi.org/10.1111/ajae.70007

Country/Region

Ethiopia

Keywords

Africa; Eastern Africa; Sub-saharan Africa; Agricultural Extension; Agricultural Technology; Fertilizer; Crop Yield; Market Access; Soil Fertility

Language

English

Access/Licence

Open AccessCC-BY-4.0

Links

https://doi.org/10.1111/ajae.70007 Source record

Record type

Journal Article

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Brief

Spatial analysis shows moderate yet significantly more vigorous crops in AICCRA communities compared to control communities

2025Song, Chun; Kramer, Berber; Obeng, Faustina; Chepsiror, Calvin; Dalaa, Mustapha; Mahama, Obed; Berti, Lorenzo; Assefa, Thomas; Nowak, Andreea C.; Tepa-Yotto, Ghislian
Details

Spatial analysis shows moderate yet significantly more vigorous crops in AICCRA communities compared to control communities

In southern Ghana, communities with multiple stakeholder CSA field demonstrations (CSA hubs) show significantly more vigorous crops based on satellite imagery from 2021 to 2025, compared to control communities.

Year published

2025

Authors

Song, Chun; Kramer, Berber; Obeng, Faustina; Chepsiror, Calvin; Dalaa, Mustapha; Mahama, Obed; Berti, Lorenzo; Assefa, Thomas; Nowak, Andreea C.; Tepa-Yotto, Ghislian

Citation

Song, C.; Kramer, B.; Obeng, F.; Chepsiror, C.; Dalaa, M.; Mahama, O.; Berti, L.; Assefa, T.; Nowak, A.; Tepa-Yotto, G. (2025) Spatial analysis shows moderate yet significantly more vigorous crops in AICCRA communities compared to control communities. Infonote, 4 p.

Country/Region

Ghana

Keywords

Africa; Western Africa; Sub-saharan Africa; Evaluation; Crop Production; Climate Change Adaptation; Climate-smart Agriculture-climate Smart Agriculture; Spatial Analysis

Language

English

Access/Licence

Open AccessCC-BY-4.0

Source

Source record

Record type

Brief

Resource thumbnail

Journal Article

Fertilizer demand and profitability amid global fuel-food-fertilizer crisis: Evidence from Ethiopia

2025Assefa, Thomas; Berhane, Guush; Abate, Gashaw T.; Abay, Kibrom A.
Details

Fertilizer demand and profitability amid global fuel-food-fertilizer crisis: Evidence from Ethiopia

We assess fertilizer demand and profitability in Ethiopia in the face of the recent global fuel–food–fertilizer price crisis and other domestic shocks. We first examine farmers’ response to changes in both fertilizer and food prices by estimating price elasticity of demand. We then evaluate the profitability of fertilizer by computing average value–cost ratios (AVCRs) associated with fertilizer application before and after these crises. We use detailed longitudinal household survey data collected in three rounds, covering both pre-crisis (2016 and 2019) and post-crisis (2023) production periods, focusing on three main staple crops in Ethiopia (maize, teff, and wheat). Our analysis shows that fertilizer adoption, and yield levels were increasing until the recent crises, but these trends have been halted by these crises. We also find slightly larger fertilizer price elasticity of demand estimates than previous estimates, ranging between −0.40 and −1.12, which vary across crops. We find that farmers are more responsive to fertilizer prices than to output prices. Farmers’ response to increases in staple prices was statistically insignificant and hence not as strong as theoretically perceived. Households with smaller farm sizes are relatively more responsive to changes in fertilizer prices. Finally, we show important dynamics in the profitability of chemical fertilizer. While the AVCRs show profitable trends for most crops, the share of farmers with profitable AVCRs declined following the fertilizer price surges. Our findings offer important insights for policy focusing on mitigating the adverse effects of fertilizer price shocks.

Year published

2025

Authors

Assefa, Thomas; Berhane, Guush; Abate, Gashaw T.; Abay, Kibrom A.

Citation

Assefa, Thomas; Berhane, Guush; Abate, Gashaw T.; and Abay, Kibrom A. 2025. Fertilizer demand and profitability amid global fuel-food-fertilizer crisis: Evidence from Ethiopia. Food Policy 133 (May 2025): 102785. https://doi.org/10.1016/j.foodpol.2024.102785

Country/Region

Ethiopia

Keywords

Africa; Sub-saharan Africa; Eastern Africa; Fertilizers; Prices; Farmers; Household Surveys; Maize; Teff; Wheat; Yields

Language

English

Access/Licence

Open AccessCC-BY-4.0

Links

https://doi.org/10.1016/j.foodpol.2024.102785 Source record

Project

National Policies and Strategies

Record type

Journal Article

News

June 12, 2025 | Press Release

New special issue of Food Policy examines fertilizer and soil health policies in the wake of global crises

Key findings were presented and discussed during the IFPRI policy seminar on June 11.