Antifungal activity of different extracts of Chenopodium album against Fusarium oxysporum f. sp. cepae, the cause of onion basal rot.

Antifungal potential of different parts of Chenopodium album L. was examined against Fusarium oxysporum Schlechtend. f. sp. cepae (Hans.) Snyder and Hansen, the cause of basal rot disease of onion (Allium cepa L.). In screening bioassays, the effect of different concentrations (0.5, 1.0, …3.0%) of methanolic leaf, stem, root and inflorescence extracts of C. album was investigated. Extracts of different parts of the test plant species showed variable antifungal activity. The highest antifungal activity was exhibited by inflorescence extract. Different concentrations of this extract suppressed fungal growth by 24–80%. Methanolic inflorescence extract was successively extracted with n-hexane, chloroform, ethyl acetate and n-butanol. The highest antifungal activity was shown by ethyl acetate fraction resulting in 68–100% reduction in fungal biomass. From ethyl acetate fraction, three unknown compounds viz. A, B and C were isolated through thin layer chromatography (TLC). TLC fraction A exhibited the highest antifungal activity with minimum inhibitory concentration (MIC) of 250 g mL -1 . Thus, antifungal constituents of ethyl acetate fraction of methanolic inflorescence extract of C. album can be used as natural fungicides for the management of basal plate rot of onion. © 2013 Friends Science Publishers