ANTIFUNGAL EVALUATION AND PHYTOCHEMICAL PROFILE OF TRICHODERMA HARZIANUM AND GLOMUS VERSIFORME SECONDARY METABOLITES ON COWPEA PATHOGENSI.O. OMOMOWO, A.E. FADIJI AND O.I. OMOMOWO
In this study, ethyl acetate crude extract of secondary metabolites obtained from strains of Glomus versiforme and Trichoderma harzianum was profiled for phytochemical constituents and antifungal potential against cowpea phytopathogens that causes powdery mildew and leaf spot diseases viz. Erysiphe flexuosa and Cercospora canescens. The phytochemical profile showed that Alkaloids, Flavonoids, Phenols, Tannins, Cardiac Glycosides, Steroids, and Saponins were all present. The antifungal inhibitory results of secondary metabolites from Glo-ver60 had the overall highest inhibition effects 55Â±0.05 mm against C. canescens and 59.7Â±0.03 mm against E. flexuosa. The metabolites obtained from Trichoderma harzianum gave the second overall highest antifungal inhibitory activity against cowpea pathogens with 53.3Â±0.07 for C. canescens and 50.5Â±0.05 mm for E. flexuosa. Generally, these results reveal that there was variation in the antifungal activity of the biofungicidal metabolites at different concentrations. The minimum inhibitory concentration and minimum fungicidal activity from these biological controlling strains of Glomus versiforme and Trichoderma harzianum on C. canescens and E. flexuosa indicated that Glo-ver60 strain gave better results compared to the other strains. Glo-ver60 gave the best result of 73.4Â±0.05 Î¼g/mL and 98.4Â±0.05 Î¼g/mL for C. canescens as well as 72.1Â±0.08 Î¼g/mL and 97.1Â±0.07 Î¼g/mL for E. flexuosa respectively. These results revealed that there was variation in the inhibitory activity of the metabolites from Glomus versiforme and Trichoderma harzianum against the cowpea pathogens and this was concentration-dependent. The results from this study have shown that secondary metabolites from these bioagents could be formulated as potential biofungicides against cowpea disease-causing pathogens.