The VlMYB149-VlHIPP30 Regulatory Module Enhances Grapevine Resistance to Botrytis cinerea by Activating the Antioxidant System and Copper Metabolism.

Grapevine, as an important economic crop around the world, has generally poor disease resistance in planting. Vitis vinifera, in particular, show high susceptibility to grey mould (caused by Botrytis cinerea), which leads to a decline in yield and quality. Existing chemical control methods have limitations, including environmental and resistance issues, so breeding disease-resistant varieties is crucial for sustainable agriculture. In this study, we identified a nuclear membrane-localised R2R3-type MYB transcription factor named VlMYB149 whose expression was significantly upregulated following grey mould infection. Overexpression of VlMYB149 in grapevine and Arabidopsis indicated that it significantly enhances resistance to grey mould, characterised by reduced lesion size and inhibited mycelial expansion. VlMYB149 increased the content of copper and increased the activities of antioxidant enzymes such as catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD). VlMYB149 also directly activated the expression of VlHIPP30, which plays a crucial role in the process of copper transport. Overexpression of VlHIPP30 has been shown to enhance disease resistance by reducing reactive oxygen species (ROS) levels and enhancing copper metabolism. Our findings reveal a novel molecular mechanism model for grapevine resistance to B. cinerea, mediated by the synergistic interaction by copper metabolism and the antioxidant system. This study not only provides crucial genetic resources for breeding disease-resistant crops but also advances our fundamental understanding of plant immunity.