IN VITRO ANTIFUNGAL ACTIVITY OF MINT, THYME, LAVENDER EXTRACTS AND ESSENTIAL OILS ON VERTICILLIUM DAHLIAE KLEB.

Abstract

Mint, thyme and lavender of Lamiaceae family were chosen as experimental materials. The aim of study was to investigate the antifungal effects of 3 medicinal plants extracts and essential oils obtained by water stem distillation method, against two pathotypes (defoliating-D and nondefoliating-ND) of Verticillum dahliae Kleb. The inhibition of the fungus mycelium growth was evaluated under in vitro conditions at the doses of plant extract in 1 %, 3 %, 5 %, 7 % and 10 % and essential oils in 2, 4, 8, 16 and 32 1 Experiment was set up at randomized plot design with 3 replications. After the end of 7 days incubation period, colony diameters were measured and % inhibition zone ratios were calculated compared to the controls. The reduction effects of mint, thyme and lavender essential oils were greater than the extracts of the same plants. Mint, thyme and lavender extracts reduced the mycelium growth of D and ND in varying degrees, however; the highest antifungal effect was observed at 10 % dose of thyme extract. 8, 16 and 32 mu 1 mL(-1) doses of thyme essential oil inhibited 100 % the mycelium growth of both pathotype and showed a significant fungicidal effect on them. Antifungal effect of mint essential oil was found to near the thyme essential oil depending on the pathotype and the applied dose.