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The three essays in this dissertation address different aspects of the impact of disease-resistant bean research in Honduras and are each based upon a random sample survey of Honduran bean farmers (N = 210) in 2001. The first essay presents evidence of recent adoption rates of disease-resistant bean varieties (RVs), the farm-level benefits of RV adoption, and the ex post rate of return to bean research in Honduras from 1982–2010. The results demonstrate that the investment in breeding disease-resistant beans in Honduras has been profitable; under the base scenario assumptions, the ex post economic rate of return to disease-resistant bean research in Honduras during the period 1982–2010 is 41.2%. In addition, adoption of RVs is widespread and scale-neutral; 42% of sample bean farmers used an RV in the postrera season of 2000.
The second essay addresses the methodological challenges involved in the evaluation of a technology which maintains rather than augments yield, and demonstrates an econometric method (borrowed from the wage differential literature) to construct appropriate counterfactuals in the estimation of the impact of maintenance research technologies. The method is applied to test for selection bias and estimate differentials between RV and traditional variety (TV) bean yields in survey data from Honduras by constructing the counterfactual to RV yields as what yields RV users would have obtained had they continued to grow TVs (i.e., the TV yield of RV users). The corrected yield model predicts that RV growers enjoy net income gains of 13 to 19% in the postrera season, compared to what they would have earned growing TVs; while the uncorrected OLS model predicts that RV growers see either no income gain or even losses by growing RVs (relative to TVs). This application demonstrates that the implications of this method are significant for the assessment of maintenance research impacts.
The third essay uses the farm survey data in probit analysis to investigate the significance and magnitude of “varietal/breeding” factors vs. “access” factors in the adoption of early and recent generation RVs in Honduras. The results indicate that adoption of early RVs, Dorado and Don Silvio, are more constrained by poor market characteristics (breeding factors) than lack of access. The poor market characteristics of these early generation RVs, reflected in average price discounts of 15% relative to TVs, has constrained adoption primarily to disease-intense areas, and has reduced the net income gains for adopters. By contrast, the results of analysis of a recent generation RV, Tio Canela (released in 1997), indicate that the market acceptance (breeding) aspects of the variety appear to be much improved over those of Dorado, as Tio Canela has been adopted in areas of both historically high and low disease pressure. However, the principal constraint to further Tio Canela adoption is information and seed access (a policy aspect). With increased access, current Dorado users (in disease-intense areas) would be expected to switch to Tio Canela and enjoy larger net incomes due to Tio Canela's smaller price discounts. The adoption of Tio Canela outside of traditionally high-disease pressure areas implies that the variety offers positive net benefits for growers in low-disease pressure areas as well.