Coumarin Decouples ROS Homoeostasis, Membrane Integrity, and HOG Signalling to Inhibit Alternaria alternata.

Coumarin inhibits Alternaria alternata growth and infection by disrupting ROS homeostasis, membrane integrity, and ergosterol biosynthesis, and activates the HOG pathway.

• Why it matters: Controlling A. alternata is crucial for preventing crop damage, yet effective, sustainable antifungal agents are limited. Understanding coumarin’s mechanisms could lead to better control strategies.
• What they did: The study used transcriptomic analysis and mutant sensitivity tests to show that coumarin significantly inhibits fungal growth, dysregulates membrane and sterol metabolism genes, and activates the HOG pathway, with increased efficacy when combined with certain fungicides.
• The result: Coumarin’s multi-target antifungal actions suggest its potential as a sustainable agent for managing A. alternata, especially when used with existing fungicides to enhance effectiveness.