The MYB transcription factor TaMYB30 enhances wheat resistance to sharp eyespot disease by scavenging ROS...

Sharp eyespot disease, caused primarily by the necrotrophic fungal pathogen Rhizoctonia cerealis, poses a significant threat to global wheat production. This study reports the functional characterization of an R2R3-MYB transcription factor, TaMYB30, which plays a crucial role in wheat's resistance to R. cerealis. The overexpression of TaMYB30 in transgenic wheat led to enhanced resistance against sharp eyespot disease, whereas its knockdown in wheat notably compromised resistance, indicating that TaMYB30 acts as a positive regulator in wheat's defense against R. cerealis infection. Comparative transcriptomic analysis between transgenic and wild-type wheat following R. cerealis infection revealed that differentially expressed genes were primarily involved in oxidative stress response, peroxidase activity, and glutathione metabolism. Further functional analysis demonstrated that TaMYB30 directly activates the expression of PRX and GST genes. Transgenic wheat with elevated TaMYB30 expression also exhibited significantly enhanced tolerance to oxidative stress compared to wild-type plants. Notably, overexpression of TaMYB30 mitigated hydrogen peroxide (H₂O₂) accumulation post-infection, suggesting that the resistance conferred by TaMYB30 is likely due to its role in scavenging reactive oxygen species (ROS) accumulation. This research uncovers a novel regulatory function for MYB transcription factors in wheat defense mechanisms and proposes TaMYB30 as a promising candidate for genetic improvement to enhance wheat's resistance to sharp eyespot and oxidative stress.