Biological control potential of endophytic fungus Talaromyces wortmannii FP-25 against multiple fungal diseases of corn and banana on Mindanao Island, the Philippines

Abstract

Importance of the work: Antagonistic fungi offer a sustainable, eco-friendly biocontrol approach for disease management, providing an effective alternative to conventional chemical pesticides. Objectives: To evaluate and propose a biological control agent from an endophytic fungal strain against three fungal pathogens: Curvularia lunata, Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) and Stenocarpella maydis. Materials and Methods: The selected fungal endophyte was characterized based on morpho-cultural assessment on artificial media and ultrastructural examination using scanning electron microscopy. Molecular identification used the internal transcribed spacer (ITS) region sequencing and phylogenetic analyses. Antagonistic potential against selected fungal phytopathogens was evaluated using dual-culture assays to determine its efficacy as a prospective biological control agent. Results: The endophytic fungus was morpho-culturally characterized and molecularly identified based on ITS region sequencing, revealing 100% sequence identity with Talaromyces wortmannii. The dual-culture assays demonstrated potential antagonistic activity of T. wortmannii FP-25 against C. lunata, Foc TR4 and S. maydis. Radial growth inhibition increased significantly from day 6 to day 12, with linear mixed-effects modeling confirming significant treatment × incubation interactions. Based on other studies, the antagonistic mechanisms may involve mycoparasitism, secretion of cell wall-degrading enzymes and production of antifungal secondary metabolites. Distinct temporal suppression patterns were observed among the evaluated phytopathogens. Main finding: The endophytic fungus T. wortmannii FP-25 acted as an effective potential biocontrol agent, suppressing pathogen inocula via competition and potential antibiosis. Its activity against multiple economically important fungal phytopathogens and its timedependent antagonism support its potential application in integrated disease management and represents the first report of biocontrol activity of T. wortmannii FP-25 against C. lunata, Foc TR4 and S. maydis in the Philippines