Secretion of antifungal metabolites contributes to the antagonistic activity of Talaromyces oaxaquensis

Abstract

Controlling fusarium wilt is critical to guarantee the supply of bananas. In this study, three strains of the endophyte Talaromyces oaxaquensis obtained from pseudostems of Musa sp. AAB cv. Manzano were found to inhibit the in vitro growth of the banana pathogen Fusarium oxysporum f. sp. cubense M5. Constitutive production and secretion of antifungal factors by T. oaxaquensis is a feature of its inhibition effect, as there was no physical contact between the two fungi. An ethyl acetate extract prepared from supernatants of liquid cultures of the three T. oaxaquensis strains displayed inhibitory activity and hyphal swellings. Both the supernatants and mycelia were subjected to metabolic profiling. Penicillides and macrolide polyesters were detected in the supernatants. A molecular docking approach revealed the binding of the polyester 15G256α to chitin synthase 1 of Fusarium oxysporum f. sp. cubense. This is the first study to report the potential of the endophyte Talaromyces from Musa sp. to generate biological control products to protect plants against phytopathogens.