Many fungi including Phytophthora species cause severe pre- and post-harvest damage to agricultural crops. Research focused on plant-derived fungicides and their possible application in agriculture is being intensified as these are having enormous potential to inspire and influence modern agro-chemical research. In this study, we survey the effectiveness of essential oil of Cymbopogon citratus (DC.) Stapf. on the mycelium growth of three species of Phytophthora including P. capsici, P. drechsleri and P. melonis. The essential oil was extracted from fresh leaves of C. citratus that were subjected to hydro-distillation through Clevenger's apparatus and its chemical composition was analyzed with Gas Chromatography-Mass Spectrometry (GC-MS). α- citral (39.16%), Z- citral (30.95%), limonene (5.83%), and caryophyllene (3.44%) were identified as main components. The rate of growth inhibition were measured after placing 7 days active mycelial plugs of each fungus on petri dishes containing CMA amended with specific concentration of essential oil and incubated at 25 ± 2 oC. Since growth inhibition of studied essential oil was evident in this study, they have potential to control of Phytophthora species and could be considered for developing new fungicides.
