Antifungal Effects Of Leaf Extracts (Ocimum Gratissimum And Aframomum Melegueta) On Post Harvest Yam Rot

ABSTRACT

Effects of Ocirnum gralissitnurn and Afrainomum me!eguela on mycelial reduction of the most occurring fungal pathogen of soft rot yam tuber were tested.The fungi isolated were Aspergilius niger, Aspergi/Ius flavus and Fusarium oxysporum. Antifungal effects of the leaves was shown on A. niger and F. oxysporum. Others observed were Rhizopus stolonifer, Botryodipiodia theobromae and Penidllhium clirysogenum. Both leaf extracts were most effective through ethanol extraction followed by cold-water extraction then hot water extraction of the leaves. Both leaves showed similar fungicidal activity. Results of pathogenicity test using A. niger, A. flavus and F. oxysporurn on the fresh yam at room temperature for 3 months showed brown lesion around point of inoculation during incubation and symptoms observed were typical of those observed on the plant in the field. So it shows that A. niger, A. fiavus and F. oxysporurn cause soft rot of yam.