Evaluation (Glasshouse conditions) of native fungal bioagents with multiple functions against Fusarium wilt disease (Foc TR4) in India

Abstract

Fusarium wilt, particularly caused by Fusarium oxysporum f.sp. cubense Race 4 (Foc TR4), poses a severe threat to banana production. This study aimed to evaluate the efficacy of various endophytic and rhizospheric Trichoderma isolates in managing Fusarium wilt disease of banana and enhancing plant growth. Fifteen endophytic and twenty-five rhizospheric Trichoderma isolates were screened for their antagonistic potential against Foc TR4. Effective isolates were identified based on their ability to inhibit spore germination and mycelial growth of the pathogen. Among the isolates, Trichoderma harzianum (Pce-1), Trichoderma asperellum (Dse-1), and Trichoderma asperellum (Pbr-1) were notably effective, showing up to 100% inhibition of spore germination and significant mycelial growth inhibition (56.25-80%). Further analysis included assessing the plant growth-promoting activities of these isolates, such as hydrogen cyanide production, phosphate solubilization, and indole acetic acid production. The isolates were also evaluated for their impact on banana plant growth and Fusarium wilt suppression in pot culture conditions. The results demonstrated that Trichoderma asperellum (Dse-1) and Trichoderma harzianum (Bkr-3) were particularly effective, achieving the lowest internal wilt scores and significantly improving plant growth parameters compared to controls. The combined application of endophytic and rhizospheric Trichoderma isolates showed enhanced efficacy, with combinations like Trichoderma asperellum (Dse-1) + Trichoderma harzianum (Bkr-3) and Trichoderma harzianum (Pce-1) + Trichoderma harzianum (Bkr-3) achieving the lowest wilt scores and notable improvements in plant growth. This study highlights the potential of using Trichoderma spp. as biological control agents for managing Fusarium wilt and improving banana cultivation.