2.6 Statistical analysis
All data were reported as means ±standard deviation of three triplicates. One-way analysis of variance (ANOVA) was applied to the data to determine differences (P < 0.05). To ascertain significant differences between the levels of the main factor, Fisher LSD (Least Significant Difference) test was applied between means. ANOVAs were made with the following factors: strains (23levels) and volume of essential oil tested (10, 20 and 30 μl with disc diffusion and vapour diffusion methods). Statistical data analysis was undertaken using XLStat (Pros statistical software, Paris, France). P values < 0.05 were considered as significant.