Alternaria solani and Phytophthora infestans are causative agents of early and late blight of tomatoes respectively which are currently controlled using fungicides. Overuse of fungicides poses safety concerns. The research objective was to investigate the invitro efficacy of Warburgia organic solvent crude extracts on blight pathogens. Warburgia ugandensis stem bark sample was air dried at room temperature then ground. The powdered material was weighed and soaked in organic solvent then filtered and the solvent recovered using a rotary evaporator. Multiple extraction method was used with four organic solvents. Well diffusion method was used to screen Warburgia extracts against A. solani and P. infestans. All assays were performed in triplicate. Statistical analysis on inhibition zone was carried out using analysis of variance (ANOVA). Warburgia ugandensis hexane crude extract had the highest inhibition zone in A. solani while methanol crude extract gave the highest mean inhibition zone in P. infestans. All the extracts were inhibitive against P. infestans and A. solani. Further studies are required for invivo studies and to analyze the bioactive compounds in the extracts.
Warburgia ugandensis, Phytophthora infestans, Alternaria solani, invitro inhibition, tomatoes, well diffusion method.