Abstract
In the present study fungicidal potential of four macrolichens Heterodermia comosa, Parmotrema margaritatum, Pseudocyphellaria aurata and Ramalina farinacea were evaluated against plant pathogenic fungi Fusarium oxysporum and Fusarium solani. The hot crude extract was extracted from solvent methanol, ethyl acetate and acetone. The highest yield of 157 mg/ml was obtained from methanol extract of Pseudocyphellaria aurata. Important phytochemical constituents like tannins, alkaloids, carbohydrates and steroids were present in most of the lichen extracts tested. Antifungal activity of the extracts was evaluated by well diffusion assay, micro dilution assay and TLC bioautographic technique. The ethyl acetate extract of Ramalina farinacea showed highest zone of inhibition against Fusarium oxysporum with 17.0±1.0 mm and Fusarium solani with 13.3±0.57 mm. Micro dilution assay showed least MIC value of 0.781 mg/ml from Ramalina farinacea and Heterodermia comosa in ethyl acetate extracts against Fusarium oxysporum and 3.125 mg/ml against Fusarium solani. Clear zones of fungal inhibition were obtained on chromatogram in the ethyl acetate extract of Parmotrema margaritatum at Rf value 0.1, 0.21, 0.48. The obtained results prove that lichens can be used as potential antifungal agents against phytopathogens. Hence lichens serves as better natural fungicides in order to keep the environment safe, and which may also increase the yield and production of the crops. Further work could be focused on the isolation and purification of active components from the studied lichens.
