Fungi toxic efficiency of some plant volatile essential oils against plant pathogenic fungi

Abstract

Plant essential oils have the potential to replace the synthetic fungicides in the management of different fungal diseases. Four different essential oils of eucalyptus (Eucalyptus globulus), citronella (Cymbopogon citrate), karanj (Pongamia pinnata) and neem (Azadirachta indica) were selected because of their high inhibitory activities against ten phytopathogenic fungi. The antifungal screening for all the four Eos clearly indicates the effective lowest concentration to control the fungal growth. The more lower the MIC value, the better antifungal potency of the relative plant volatile E. globulus. Among the plant volatile essential oils, eucalyptus oil showed the lowest minimum inhibitory concentration (MIC), i.e.  0.5 mg/disc. Higher MIC values were registered, in the order, for citronella, karanj and neem oils, singly used to control all the ten fungal pathogens. Highest zone of inhibition (ZI) values followed the same pattern. These results indicated that plant volatile essential oils after suitable formulation could be used to control of different fungal pathogens. This may encourage the farmers to produce organic commodities to generate more revenue. Key words Essential oils, minimum inhibitory concentration (MIC), zone of inhibition, fungal disease.