Screening of sweet potato feathery mottle virus resistant sweet potato (Ipomoea batatas L., Lam.) cultivars in Kebbi State, Nigeria

Abstract

Sweet potato is a food security crop because of its ability to withstand adverse climatic conditions. This security, however, is being threaten by viral diseases and use of resistant cultivars remain the best management. This research was conducted to screen cultivars of sweet potato against sweet potato feathery mottle virus (SPFMV) infection. The treatments consisted of five cultivars coded as CV1, CV2, CV3, CV4 and CV5, respectively. The asymptomatic experimental plants were established, maintained under screen house conditions and graft-inoculated using infected vines which were tested SPFMV positive using both Double Antibody Sandwich Enzyme-Linked Immunosorbent Assay (DAS-ELISA) and Polymerase Chain Reaction (PCR). The experiment was laid out in Completely Randomized Design (CRD) and replicated three times. Results obtained from disease incidence and symptom severity indicated that there was significant difference (P <0.05) among cultivars in their reaction to SPFMV infection. CV2 had the highest mean disease incidence (60.67%) while, CV3 had the lowest mean disease incidence (36.67%). CV1, CV3, and CV5 have the same lowest mean symptom severity score of 2.00 while, CV2 had the highest mean severity score of 4.00. Based on the reaction of the cultivars after inoculation, it could be concluded that, all the cultivars screened were susceptible to SPFMV but CV1, CV3 and CV4 cultivars have some degree of resistance to SPFMV infection and were therefore recommended for use by the farmers in the study area. This is the first research that screened sweet potato cultivars for resistance to SPFMV in Kebbi State, Nigeria.