Damping off and Fusarium wilt of melon, caused by Phytophthora melonis and Fusarium oxysporum f. sp. melonis respectively, are important disease affecting melon production in many countries throughout the world. Both pathogens are the soil-borne fungus and survives in the soils as oospores and chlamydospore for several years [1].Damping off and Fusarium wilt of melonis are an economicaly imortant disease in Iran. Fusarium oxysporum f. sp. melonis invades plant vascular tissues and induces severe wilting of the foliage by blocking xylem transport and impeding the movement of water. But, Phytophthora melonis can cause crown, and root rot, and stem and leaf blight disease in melon. In this study, we survey the antifungal activity essential oil of Bunium persicum and Allium sativum against Fusarium oxysporum f. sp. melonis and P. melonis respectively in vitro and greenhouse conditions in different concentration. The in vitro test consisted of evaluating the development of colonies of pathogens on Potato Dextrose Agare medium supplemented with the plant essential oils at various concentrations. Also, in vitro the median effective concentration (EC50) values of plant essential oils was calculated. In greenhouse conditions, pasteurized soil infested with pathogen and the essential oils added to soil surrounding the roots of melon plants. Also, control treatments were carried out. The chemical composition of the essential oils was determined by gas chromatography-mass spectrometry (GC-MS). Also, Data were analyzed using SPSS software. The results showed that Bunium persicum essential oil were very effective on Fusarium oxysporum f. sp. melonis. Maximum and minimum EC50 values of oil on this pathogen was 341.3 and 217.71. The mean EC50 values for Allium sativum on P. melonis was 45.38. Both essential oils were able to inhibit mycelial growth of pathogens. Results of greenhouse indicated that plant essential oils were able to reduce disease severity in melone. The profile of
