by using modified micro-atmospheric method (in vitro) previously described by Singh et al. (1999) with some modification.
PDA plates were prepared using 5 cm Petri dishes containing 5 mL of PDA. A 4 mm (diameter) agar disc of B. cinerea was cut from the periphery of the active growth culture (3 - 5 days old) and the mycelial surface was placed upside down on the centre of the dish. The Petri dish was then inverted and a small paper disc (6 mm diameter, Whatman No.1) was placed inside on the lid of each Petri dish. An aliquot amount (5, 10, 15, 20 and 25 μl) of each essential oil was applied to the paper disc. Incubation of the fungus and test was conducted in a growth chamber at 23 °C with 12/12 dark-light regime. Each test was replicated for three times. The antifungal activity was determined after 3 day incubation by means of the percentage of inhibited redial growth as following equation:
% inhibition = ∆do − ∆d × 100 ∆do
Where ∆do and ∆d are the average diameter of the fugal colonies in the control and treatment sets, respectively
Determination of the nature of the inhibition of essential oil
To determine the nature of the inhibition of each essential oil, the mycelial discs which were totally suppressed by the essential oil were transferred to a PDA plate which was not supplemented with the essential oil. The treatment was fungistatic if the growth of the fungus
began again and was considered fungicidal if the fungus did not re-grow.