Patrick K. Koech^1,, Javan O. Were¹, Linnet S. Gohole¹, Beatrice A. Were², Billy A. Makumba³

Bacillus amyloliquefaciens is a bio control agent that is reported to promote plant performance alongside having antifungal properties. The bacterium is found often naturally around the rhizosphere of and normally colonizes sorghum roots. To counter the adverse effects of sorghum foliar diseases, the inhibitory potential of Bacillus amyloliquefaciens bacterium was tested against isolated foliar disease causing pathogens. This experiment was done under in vitro conditions in a completely randomized design where four isolates; Colletotrichum sublineola, Sporisorium sorghi, Exserohilum turcicum and Gloeocerspora sorgi where treated with Bacillus amyloliquefaciens in three replications. Mycelial growth inhibition was assessed by taking measurements on isolate growth towards the control agent as a subject to the distance travelled away from the control agent and expressed as a percentage. To further this assessment, a greenhouse experiment was set where, different rates of Bacillus amyloliquefaciens bacterium was assessed against covered kernel disease. This was done in a completely randomized design with three replications. From the study, the bacterium significantly reduced the mycelial growth of the test fungi where Colletotrichum sublineola was the most inhibited by 58 % while Exserohilum turcicum was least inhibited by the bacterium (35%). On the other hand, increasing bacterium treatment rates consequently reduced covered kernel disease severity compared to control where no bacterium was applied. Bacillus amyloliquefaciens should be included in an integrated disease management system as seed dressers to reduce prevalence of sorghum foliar diseases in Western Kenya.

Bacillus amyloliquefaciens, foliar diseases, sorghum, management