Potato (Solanum tuberosum) seed production is a critical element of the potato industry in Zimbabwe. The potato industry is affected by poor seed quality due to potato bacterial wilt (Ralstonia solanacearum), a pathogen known to be highly destructive in most Solanaceous crops. The main objective of this study was to determine the distribution, prevalence, incidence of potato bacterial wilt (PBW) in the Nyanga potato seed quarantine area. The study was conducted using an intensive survey, whereby a questionnaire was administered to all 19- potato seed producers in the quarantine area. Spot altitude of the farms was recorded using GPS and a map of bacterial wilt distribution was developed. Percentage disease prevalence was determined by counting the number of potato fields with bacterial wilt expressed as a percentage of the total number of fields assessed in each farm and the disease incidence was determined through visual observations of plants showing the wilting symptom. Out of 19 farms surveyed, ten farms had bacterial wilt present. The prevalence in the Nyanga potato quarantine area varied from 100% to 0%, while the incidence also varied from 0% to 66.7% in the farms surveyed.

Keywords: Potato bacterial wilt, prevalence, incidence, quarantine, Trichoderma, Ralstonia solanacearum