Antifungal Activity Of Viscum Album (AFRICAN MISTLETOE) Leaf Extract On Dioscorea Rotundata (POIR) (WHITE YAM) Tuber Rot Disease
This study aimed at evaluating the antifungal activities of leaf extract of Viscum album (6.25, 12.5, 250, 80 and 100mg/l along with mancozeb 0.3g/ml on rot reduction and on mycelia growth inhibition of yam tuber rot pathogens. Antifungal susceptibility test, minimum inhibitory concentration against the fungal pathogens were performed by disc diffusion method. The bioactive principles were isolated by extraction and then analyzed by GC-MS SHIMADZU QP 2010, Japan while the identification of the bioactive compounds was done by comparing their mass spectra and retention indexes with those of National Bureau of standards library and other published spectra. Results showed that Aspergillus niger, Fusarium oxysporium Botryodiplodia theobromae and Geotrichum candidum were associated with yam rot.Diameter of inhibition result showed that petroleum ether extract was more effective in inhibiting the growth of the fungal pathogens than methanol extract V.album was found to show low MIC value (25mg/l). In vivo result showed that V.album extract reduced tuber rot caused by different fungal pathogens. B.theobromae was most devastating causing rot area of 6.31cm2 but was drastically reduced after treatment with V.album extract to 2.18cm2 The least divastating fungi was G.candidum causing rot area of 2.75cm2 and was reduced to (2.00cm2) after treatment with V.album extract. Two compounds, caprylamide and linolelaidic acid methyl ester were identified as the major antifungal compounds present in the leaves of V.album. It can be suggested that use of V.album would be helpful in the treatment of mycotic infections and in the control of fungal plant diseases.
Keywordsó Antimicrobial, GC-MS, pathogens , tuber rot, V.album.