Biocontrol of Bacterial Diseases of Bell Pepper (Capsicum Annuum L.) Using Potassium-Solubilizing Bacteria in Umudike, Abia State, Nigeria

Post-harvest deterioration is a threat to Bell pepper production. This research studied the isolation, identification and control of pathogens associated with Bell pepper in Umudike. The experiment was conducted at the Crop and Soil Science Laboratory, Michael Okpara University of Agriculture, Umudike (MOUAU), from February to April 2026, using potassium-solubilizing bacteria (Bacillus cereus and Pseudomonas aeruginosa) isolated from the root of Althernanthera bettzickiana weed and sterile water as the control. Diseased Bell peppers were collected from the market and taken to the laboratory, and parameters assessed were identification, pathogenicity tests and antimicrobial inhibition assays. A completely randomized design (CRD) was used; data were replicated three times and analyzed using SPSS. Results from the isolation, identification and pathogenicity test showed Ralstonia spp and Pectobcterium carotovora as pathogens of Bacterial disease of Bell pepper. The Antimicrobial assay revealed that Bacillus cereus KSB showed the highest inhibition zone diameter range of 23.5+- 2.0 -18.4+-1.2mm against the two pathogens identified, while the control (water) had the least inhibitory zone. Therefore, it is recommended that Bacillus cereus KSB be used in the control of bacterial diseases of Bell pepper in Umudike, South Eastern Nigeria