The consequence in misuse of chemical biocides for controlling pest and disease has drawn the attention of policy makers in development of methods potentially available in nature for the purpose. One of the new and safe methods of controlling pest and disease is the usage of essential oils from medicinal plants. In the present investigation, inhibition of radial growth and spore germination of post-harvest important fungi (Penicillium italicum, P. digitatum and Alternaria citri) exposed to the different concentrations of essential oils of some medicinal plants (Thymus vulgaris, Mentha piperita, Satureja hortensis, Cuminum cyminum and Trachyspermum copticum) were studied. The concentrations of essential oils examined were 250, 500 and 1000 mg/l. All the data were statistically analyzed. The results showed that the radial growth of P.italicum was completely inhibited by Th. vulgaris (500 mg/l), S. hortensis and T. copticum (1000 mg/l). The radial growth of P.italicum exposed to C. cyminum and M. piperita essential oil (1000 mg/l) was decreased (57.17% and 36.8%, respectively). The radial growth of P. digitatum was also completely inhibited by Th. vulgaris, T. copticum (500 mg/l) and S. hortensis (1000 mg/l). The radial growth of P. digitatum exposed to essential oils of C.cyminum and M. piperita were decreased 22.8% and 12.15%, respectively. A. citri’s radial growth was completely inhibited by Th. vulgaris (250 mg/l), T. copticum and S. hortensis (500 mg/l), C. cyminum (1000 mg/l). M. piperita essential oils (1000 mg/l) decreased the radial growth of A. citri to be 59.44%. Therefore, the inhibitory potency of essential oils on the post-harvest disease of citrus fruits was as Th. vulgaris> T. copticum> S. hortensis> C. cyminum> M. piperita and the extent of inhibition of fungal growth depended on the concentration of essential oils usage. These results clearly indicated that it is necessary to focus on practical application of the essential oils for inhibition of post-harvest pathogen growth and these compounds could be used as a substitute for chemical fungicides since they are natural and not toxic to humans.

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