Assessment of the empowerment of sweetpotato farmers for on-farm virus detection and production of clean planting material in Uganda

Abstract

Viral diseases significantly constrain sweetpotato production. While laboratory-based virus cleaning techniques can generate clean planting material, they are often costly and inaccessible to smallholder farmers. This study evaluated a low-cost, farmer-led approach for virus detection and production of virus-free vines using Ipomoea setosa as an indicator plant. Farmers’ groups in Iganga, Bukedea and Mpigi districts were trained on field-based virus detection and macropropagation of virus-free sweetpotato vines in the screenhouses. The training included practical sessions on vine sampling, grafting onto I. setosa, symptom observation, and propagation of clean material. Ten farmers from each of the three districts (Iganga, Bukedea and Mpigi) were trained as future trainers of trainees. After training, farmers’ results on virus indexing and macropropagation were similar to those of experts, indicating that the empowerment was successful. Symptoms of viral infections were studied on I. setosa grafted with apparently healthy sweetpotato vines. Sweet potato feathery mottle virus (SPFMV) was the most prevalent across all sites, followed by Sweet potato chlorotic stunt virus (SPCSV). Sweet potato leaf curl virus (SPLCV) was less common and detected only in Iganga and Bukedea. Mpigi had the highest virus incidence (54% SPFMV, 13% SPCSV and 4% Sweet Potato Virus Disease [SPVD]), followed by Iganga (35% SPFMV, 2% SPCSV and 4% SPLCV) and Bukedea (5% SPFMV, 2% SPCSV and 1% SPLCV). Within three months, trained farmers produced 103,610 vines in Iganga, 107,798 in Mpigi and 97,237 in Bukedea. These results demonstrate the feasibility of a decentralized clean seed production system. Scaling up this approach nationally can enhance sweetpotato productivity, household incomes, and food security. Key words: Clean seed systems, Ipomoea setosa, macropropagation, smallholder farmers