Endophytic Fungi Isolated from Musa acuminata 'Dwarf Cavendish' and their Activity against Phytopathogenic Fungi

Abstract

Endophytic fungi were isolated from Musa acuminata ‘Dwarf Cavendish’ harvested from 100-year-old crops. The antagonistic bioactivity and the inhibitory activity of the endophytic fungi were evaluated against various phytopathogenic fungi: Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder y Hansen, F. oxysporum Schlect. f.sp. cubense (E.F. Smith) Snyd. & Hans, F. moniliforme (Sheldon), Alternaria alternata (Fr.) Keissl, Geotrichum sp, Phoma sp. and Cladosporium sp. In dual culture assays, endophytic strains of Penicillium, Aspergillus, Fusarium and Chaetomium were found to be active against some of the targeted microorganisms. Four active extracts were fractionised using VLC (vacuum liquid chromatography) and two ethyl acetate and ethanolic extracts obtained from Aspergillus oryzae isolate led to two active hexanic and ethyl acetate fractions which inhibited growth of F. moniliforme (%I = 48.02 and 55.1, respectively; at 1 mg ml?1). The smallest EC50 (0.74 mg ml?1) was observed in an extract obtained from a strain of Penicillium sp. The same endophytic strain inhibited F. oxysporum by 59.72% in VOC (volatile organic compounds) assays.