Final report: Tropical legumes cluster evaluation
Creators: name: Blair, Randall
name: Danz, Jeremy
name: Harris, Anthony
name: Koleros, Andrew
name: Quiñones, Esteban J
name: Sander, Rachel
name: Shieh, Jacqueline
Publisher: name: Gates Open Research
Year: 2023

description: <b><i>Summary:</i> </b>A comprehensive review of a multi-country program to improve tropical legume seed systems in sub-Saharan Africa found strong evidence that CGIAR investments in variety development, seed production, and extension increased farmer adoption of improved varieties and increased yields of common bean in East Africa and cowpea in West Africa.<br> <br> <b><i>Purpose and Subject: </i></b>This evaluation aimed to synthesize the implementation and results of the Tropical Legumes (TL) project, implemented by three CGIAR centres (ICRISAT, CIAT and IITA) together with national agricultural research system (NARS) partners in sub-Saharan Africa and South Asia. With approximately $67 million in funding from the Bill &amp; Melinda Gates Foundation from 2007 to 2019, CGIAR and NARS staff supported six crops—chickpea, cowpea, groundnut, common bean, pigeonpea, and soybean—across Eastern, Western, and Southern Africa, as well as India and Bangladesh. <br> <br> <i><b>Approach and Methods:</b></i> The evaluation used a contribution analysis approach, whereby researchers used a range of quantitative and qualitative data to (1) determine whether the outcomes in TL’s theory of change occurred as planned, and (2) assess TL’s role in these changes vis-à-vis other actors and factors. Whenever possible, we simulated (imperfect) counterfactuals to better understand the effect of TL investments on adoption and yields. This included a difference-in-difference approach to determine whether countries that received TL assistance outpaced neighboring countries in legume yields. <br> <br> <i><b>Data:</b></i><b> </b>This evaluation leveraged existing TL documentation, journal articles, and household survey data for all analysis. Data from the <i>Living Standards Measurement Study - Integrated Surveys on Agriculture</i> (LSMS-ISA) and TL adoption surveys provided estimates of legume production and yields for rural households, and public Food and Agriculture Organization of the United Nations (FAO) data provided estimates of production and yields at national levels. Researchers conducted interviews with a small set of TL stakeholders and outside experts to validate findings.<br> <br> <b><i>Findings:</i> </b>An in-depth analysis of farmer adoption in Tanzania and Nigeria found moderate adoption rates of TL-promoted varieties of common bean, cowpea, and groundnut, ranging from 14 to 33 percent of household land under legume cultivation. Improved varieties developed, produced, and promoted under TL had higher yields than older improved varieties and non-improved varieties, particularly in the case of common bean in Tanzania (where TL-promoted variety yields were 33 percent higher than non-improved varieties). A separate difference-in-difference analysis of national trends revealed that countries that received TL assistance outpaced neighboring countries in legume yields from 2007 to 2020—particularly in the case of common bean in East Africa. Taken together, these analyses suggest that yield boosts associated with TL-promoted varieties contributed to positive national yield trends. <br> <br> <i><b>Acknowledgement:</b></i><b> </b>This evaluation was commissioned under EVITA (Evaluating Inclusive Transformation in Agriculture), which generates evidence on the outcomes and impacts of investments made by the Agricultural Development Team (AgDev) at the Bill &amp; Melinda Gates Foundation and aims to increase the efficiency of and maximize collective learning from AgDev's evaluations. Underlying household-level data from TL adoption surveys is accessible here on Harvard Dataverse.