Int.J.Curr.Microbiol.App.Sci (2015) 4(1): 710-715 710 Original Research Article Antifungal activity of Acorus calamus against Fusarium oxysporum f. sp. lycopersici Pratibha Rawal 1 , R.S.Adhikari 1* , K.Danu 1 and A.Tiwari 2 1 Kumaun University Nainital, Botany Department, L.S.M. Govt. P.G. College Pithoragarh, Uttarakhand, India 2 Botany Department, M.B.P.G. College, Haldwani, Uttarakhand, India *Corresponding author ABSTRACT Introduction Nature has been a source of medicinal components since the beginning of the civilization (Nostro et al., 2000), and an impressive number of valuable drugs have been isolated from natural sources. Most of them play a very important role in herbal health care. Approximately more than 80% population depends on herbal medicinal system for their primary health. Plant products also have an important role in health care system of remaining 20% who reside in developing countries (WHO, IUCN, WWF, 1993). In developed countries medicinal plants are extremely important, about 119 chemicals derived from plant species can be considered as important drug in use (Mullholland, 2000). A medicinal plant is any plant which in one or more of its organ contains active substances which are called as secondary metabolites and are used in therapeutic purposes. Plants have an almost limitless ability to synthesize aromatic substances, most of which are phenols or their oxygen substituted derivatives (Geissman, 1963). Most are secondry metabolites, of which at least 12,000 have been isolated, a number estimated to be less than 10% of total (Schultes, 1978). These active compounds International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 4 Number 1 (2015) pp. 710-715 http://www.ijcmas.com Knowing the tremendous antimicrobial and antifungal potential of medicinally important plants, Acorus calamus used in Indian folklore medicine was chosen to screen its antifungal activity. Rhizome extracts of the plant were prepared in organic solvents namely methanol, ethanol petroleum ether and in aqueous solution as well and tested against fungal pathogens Fusarium oxysporum f. sp. lycopersici by paper disc diffusion assay. Zone of inhibition were obtained against Fusarium oxysporum f. sp. lycopersici in case of all the solvents and aqueous extracts too. The solvent concentration with highest antifungal activity recorded was (29.5mm) acetone extract at its 1000 mg/ml concentration against Fusarium oxysporum f. sp. lycopersici. Similarly ethanol, aqueous and petroleum ether extracts were also effective. Rest of the plant extracts exhibited moderate to minimal antifungal activity. MIC was also determined for each solvent. Keywords Antifungal, Zone of inhibition, MIC, Acorus calamus, paper disc diffusion assay