Responses of common enset (Ensete ventricosum) varieties in Ethiopia to Xanthomonas and virulence of Xanthomonas strains

Abstract

Enset is a vital food crop for over 20% of the population living in Ethiopia. Enset bacterial wilt (EBW) disease caused by a pathogen Xanthomonas vasicola pv. Musacearum (Xvm) is among the challenges for its production. This study evaluated the tolerance level of enset varieties in Gamo highland against Xvm. During the field survey, EBW infected enset samples were collected for isolating and characterizing Xanthomonas responsible for causing EBW disease. The isolates were used for infecting different enset varieties in the field. Soil samples were also collected from the farm before enset cultivation (F-BC), during enset cultivation (F-DC), and after EBW disease development (F-AD). Among 126 bacterial isolates, 18 Xvm were found to yield amplicons at 420 bp using Xcm-36 as a specific primer. During pathogenicity tests, all Xvm isolates caused EBW disease before 38 days in the Bodha enset variety. Except for the variety Maze, all the field-tested varieties began to show a typical wilt symptom after 45 days of infected enset cultivation. Isolate X-D5 showed a significantly (P ≤ 0.05) higher virulent capacity to all enset varieties tested than isolates X–B4 and X–K4. Overall, findings of the fieldwork provide clues on the traditional knowledge of characterizing different enset varieties for susceptibility and tolerance to Xvm that can be useful in designing EBW disease management strategies.