Economic assessment of losses due to fruit fly infestation in mango and the willingness to pay for an integrated pest management package in Embu district, Kenya

Mango production is a major form of income generation for Kenyan large and small-scale farmers. However, it is confronted with the major threat of fruit fly infestation which causes reduction of quality and quantity of marketable fruit resulting to considerable produce losses. New and cheaper methods to reduce fruit fly infestation levels in mango production have been developed, but farmers’ willingness to pay (WTP) for them is not known. First, this study was conducted in Embu district, and it aimed to examine the magnitude of losses caused by fruit flies at the farm level via rejections during harvest using descriptive analysis and seeks to determine farmer and farm-level factors influencing the variation of these losses among mango producers using a simple robust regression technique. Secondly, a survey based on contingent valuation was conducted to obtain the maximum amount of money that mango farmers were willing to pay for an Integrated Pest Management (IPM) fruit fly control package if it is released in the market. Using a logistic regression model the study then investigated factors influencing the probability that farmers would be willing to pay a pre-determined seasonal cost of KES 1100 per acre for the package. The model was estimated using data collected from 240 mango growing farmers selected using multistage and proportionate to size random sampling procedures. Results from the study indicate that the average percentage loss due to fruit fly infestation via rejections at the farm was 24 percent, with some farmers reporting higher losses of up to 60 percent. The results further showed that fruit fly related mango losses increase with the area under mango cultivation and the farmer’s age while access to information on pest control, annual income and orchard sanitation are associated with lower losses. Results from the WTP analysis showed that 66 percent of respondents were willing to pay the cost of KES 1100 per acre for the IPM fruit fly control package. The descriptive mean WTP among farmers was found to be KES 1700 per acre implying a high potential for its adoption as it is higher than the pre-determined seasonal cost. Farmers’ WTP for the package is positively influenced by a host of factors; level of education, mango cropping system, household income, the magnitude of fruit damaged by fruit fly, damage rating and expenditure for pest control using pesticides. Based on the empirical results, the study derives policy implications in the design and implementation of workable policies that support sustainable dissemination of IPM technologies if the expected high demand and potential benefits to farmers are to be realized. A more systematic ex-post impact assessment study should however be conducted after the release and adoption of the technology to evaluate the performance of this intervention.