Effect of Essential Oils from Two Aromatic Plants on Fusarium Moniliforme Sheld. Isolated from Oryza Sativa Linn.

Abstract

Antifungal activity of essential oils ofEucalyptus citriodoraHook.andCymbopogon citratus(DC) Stapf.against Fusarium moniliformeSheld.was studied in two ways; onebyanalyzingthe mycelial growth of test fungus in different concentrationsofessentialoilsin 10, 15 and 20days and secondby analyzing the direct infection of the fungus on oil treated rice seeds. The infected sample of rice plant was collected from NARC andFusarium moniliformewasisolated through blotter test method. The essential oils were extracted through hydrodistillation process using Clevenger oil extracting apparatus and were diluted with 95%ethanol and distilled water giving concentration of 1.2, 2.5, 3.7, 4.9, 6.2, and 12.4µl ml forin vitro treatment whereas 0.04, 0.08, 0.12, 0.16, 0.2, 0.4, 0.8, 1, 1.2 and 1.4mlg for seedtreatment. TheMinimum Inhibitory Concentration (MIC)value of both the oils for in vitro treatmentwas6.2µl ml -1 forEucalyptus citriodoraand 4.9µl ml -1 forCymbopogon citratus.Both theoilweretherefore significantly (p < 0.05, LSD = 5.41) effective to arrest the mycelial growthof the test fungus. Furthermore the negative correlations between the colony size of the testfungus and oil concentrations clearlysupports the antifungal activityof these oils. The maximum inhibition i.e.90%at 1.4mlg -1 forCymbopogonoil and75% at 1.4mlg forEucalyptus oil were observed during direct rice seed treatment. Thus from comparativeanalysis of both the oils it was concluded that the oil of Cymbopogon citratus is more effective than theoil of Eucaly ptuscitriodora.