Harnessing antifungal metabolites from macro basidiomycetes against wilt inciting <i>Fusarium</i> spp.

Abstract

Plant diseases especially wilt disease caused by Fusarium spp. pose a major threat to the cultivation of vegetables. In the present study, experiments were undertaken to explore the potential antifungal metabolites produced by macro basidiomycetes viz., Lentinus edodes, Ganoderma lucidum and Schizophyllum commune against Fusarium oxysporum and F. solani causing wilt disease of cucumber and capsicum. Among these, the ethyl acetate fraction of Cell-Free Culture Filtrate (CFC) of L. edodes exhibited maximum per cent inhibition of the mycelial growth of F. oxysporum and F. solani (61.11 and 57.77 %, respectively) at a concentration of 2000 ppm. Characterization of antifungal metabolites of Cell Free Condensate (CFC) of ethyl acetate fraction of L. edodes observed as prominent bands in Thin Layer Chromatography (TLC) indicated with an RF value of 0.25 and 0.69. Further GC-MS characterization of TLC-eluted compounds from L. edodes indicated the presence of 14 different compounds including 2H-pyran-2-one 6-pentyl-, possessing antifungal activity. The Fouriertransform Infrared Spectroscopy (FTIR) spectrum revealed the functional groups such as alcohol (O-H), amides (C-O), aliphatic polyes (CH2), triazenes (N=N), silicon compounds (Si-O-Si), amines (C-N) and phosphorus (P=S). The comparison of metabolite distribution patterns by Principal Component Analysis (PCA) obtained from L. edodes (PC 1) showed a positive correlation between the compounds. This study infers that L. edodes possess antifungal activity against F. oxysporum and F. solani that can be explored for formulation and application of these antifungal compounds in plant protection.