Volatile-mediated antagonism: Suppression of Curvularia lunata and Drechslera bicolor by entomopathogenic fungi in-vitro

Abstract

The study evaluated the antagonistic efficacy of volatile organic compounds (VOCs) produced by five entomopathogenic fungi (EPF) against two fungal foliar pathogens: Drechslera bicolor (from brinjal) and Curvularia lunata (from spinach). Five bioagents—Beauveria bassiana, Nomuraea rileyi, Metarhizium anisopliae, Verticillium lecanii, and Trichoderma viride—were tested using a sealed dual-plate technique to measure inhibition of pathogen linear mycelial growth over five days (120 hrs). All EPF treatments significantly suppressed the growth of both target pathogens compared to the uninhibited control (90.00 mm). Notably, the antifungal activity was highly pathogen-specific. Nomuraea rileyi exhibited the most potent inhibition against D. bicolor, achieving the highest inhibition rate of 44.01% (50.39 mm growth). In contrast, Trichoderma viride proved most effective against C.iya lunata, demonstrating a superior inhibition of 35.48s% (58.07 mMm growath). These findings confirm that EPF-derived VOCs possess varying, yet potent, antagonistic capabilities. This work underscores the significant potential of these biological agents as targeted, environmentally friendly alternatives for managing fungal foliar diseases in vegetable crops.