Farmers’ willingness to pay for virus-free sweet potato vines in Central Uganda: A case of Mpigi and Wakiso Districts

Abstract

Several studies on sweetpotato in Uganda acknowledge scarcity of quality sweetpotato vines as one of the key constraints affecting sweetpotato production. The quality of planting material is mostly compromised by the accumulation of viruses leading to development of the devastating sweetpotato virus disease (SPVD). There are a number of initiatives in Uganda for production and multiplication of virus-free sweetpotato vines in order to timely supply adequate quantities of quality planting material. However, success of these initiatives and sustainability through private sector investment will highly depend on farmers’ willingness to pay for the virus–free sweetpotato vines. This study was carried out in Mpigi and Wakiso districts that are prone to SPVD, with a major aim of investigating farmers’ willingness to pay (WTP) for virus-free sweetpotato vines. Specific objectives included: i) characterizing sweetpotato farmers in central Uganda, ii) estimating the price farmers are willing to pay for virus-free sweetpotato vines, iii) determining factors affecting farmers’ willingness to pay for virus-free sweetpotato vines, and iv) estimating the market potential for virus-free sweetpotato vines. Primary data for the study were collected using a semi-structured questionnaire, from a randomly selected sample of 200 sweetpotato farmers. Contingent valuation methods were used to estimate willingness to pay. Data were analyzed using t-tests, chi-square tests and a Tobit model was used to evaluate factors affecting farmers’ willingness to pay for virus-free sweetpotato vines. Farmers who were willing to pay prices above the production cost for virus-free sweetpotato vines were aged over 45 years and produced sweetpotatoes mainly for commercial purposes. Farmers’ mean price for virus-free sweetpotato vines was estimated at UShs 8,660 (US$ 3.5) per bag. Factors that significantly influenced farmers’ WTP for virus-free sweetpotato included market access, revenue from sweetpotato, purpose for sweetpotato production, farmer having used high yielding varieties and district of residence. The market potential for virus-free sweetpotato vines in Wakiso and Mpigi districts, was estimated at UShs 36.9 billion (US$ 14.8 million) per year. The potential supply volume of virus-free vines was estimated at 4.3 million bags per year and the price at which market potential would be optimized was UShs 10,000 per bag. In general, vine production was found to be an economically viable enterprise and vine producers should target commercial sweetpotato farmers.