Aims The study aimed at identifying volatile organic compounds (VOCs) produced by the non-pathogenic Fusarium oxysporum (Fo) strain CanR-46, and to determine the anti-fungal spectrum and the control efficacy of the Fo-VOCs.
Methods The Fo-VOCs were identified by GC-MS. The antifungal activity of the Fo-VOCs was tested using the double-dish method. Soil contaminated with Verticillium dahliae was fumigated with the Fo-VOCs to test the control efficacy. The GFPtagged derivative strain CanR-46GFP was tested to colonize cotton roots for prevention of infection by V. dahliae.
Results Nineteen VOCs were identified with eremophila-1 (10),11-diene being the most abundant. The Fo-VOCs inhibited mycelial growth of 14 fungal species including V. dahliae, delayed V. dahliae conidial germination, suppressed V. dahliae germ-tube elongation, and caused V. dahliae hyphal shriveling and collapse. Four synthetic chemicals, 5-hexenoic acid, limonene, octanoic acid and 3,4-2H-dihydropyran, in the FoVOCs profile showed antifungal activity against V. dahliae. The Fo-VOCs significantly (P