Integrated management of ginger bacterial wilt (Ralstonia solanacearum) in Southwest Ethiopia

Bacterial wilt incited by Ralstonia solanacearum is the most important disease threatening ginger production in southwestern Ethiopia. A field experiment was conducted to determine the effect of integrated management methods on bacterial wilt disease and yield of ginger. Thus, a total of seven treatment combinations comprising hot-water, bio-fumigation, soil-solarization, Mancozeb, and bleaching powder were tested in a randomized complete block design with three replications. Data on disease incidence, yield, and yield components of ginger were collected from a random sample of plants. Then, analysis of variance (ANOVA) was performed using R-studio 9.9 statistical software, and the means were compared by the least significant test. The results from ANOVA revealed that the incidence of bacterial wilt, rhizome yield, and its components were highly significantly (P < 0.001) affected by management methods. An integrated application of rhizome seed treatment (0.1 L-1) and soil drenching (0.3%) using Mancozeb, lemongrass for soil bio-fumigation at a rate of 10 t ha(-1), along with solarization significantly reduced the incidence of bacterial wilt, the disease progress over time and produced the highest rhizome yield per hectare. Seed soaking and soil drenching in Mancozeb along with bio-fumigation was effective in reducing the disease, but a comparative yield advantage was gained through the application of bleaching powder as a seed treatment at 10% solution and soil amendment at a rate of 25 kg ha(-1), along with bio-fumigation. Thus, a combined application of Mancozeb, bio-fumigation using lemongrass, and solarization with polyethylene plastic sheet can be applied to control ginger bacterial wilt disease. Alternatively, bleaching powder, bio-fumigation with lemongrass and solarization can also be used as an integrated management system against the disease.