Grapevine LysM-containing receptor-like kinase VvLYK6 enhances resistance to white rot in tomato

Grapevine ( Vitis vinifera ) is a fruit that is widely cultivated worldwide, but white rot, caused by Coniella vitis , significantly impacts its yield and quality. The lack of resistance genes poses a major challenge to breeding grapevine varieties resistant to white rot. The LysM-containing receptor-like kinase (LYK) family genes are known to mediate immune responses to pathogens by recognizing pathogen-associated molecular patterns. To explore the resistance genes underlying white rot resistance, whole-transcriptome sequencing was carried out on grapevine cv. Guifeimeigui (GF, resistant phenotype) and cv. Red Globe (RG, susceptible phenotype) after challenge with C. vitis . Functional characterization and mechanistic analysis were conducted through virus-induced gene silencing (VIGS) in grapevine, stable overexpression in grapevine calli, and heterologous expression in tomato ( Solanum lycopersicum ). Differentially expressed genes (DEGs) enriched in the “Plant-pathogen interaction” pathway were identified, followed by expression clustering analysis to pinpoint 14 candidate genes. Silencing of VvLYK6 in GF resulted in a significant reduction in resistance to white rot, while its overexpression in grapevine calli inhibited the growth of C. vitis . VvLYK6 is localized to the cell membrane. SlLYK1 was involved in the resistance to C. vitis in tomato that was mediated by VvLYK6 . The overexpression of VvLYK6 in tomato also activated the salicylic acid signaling pathway and upregulated related pathogenesis-related genes, moreover induced a burst of reactive oxygen species, thereby increasing resistance to white rot. This study identifies VvLYK6 as a critical regulator of white rot resistance, and reveals its immune mechanism, and highlights its potential as a target for breeding and genetic improvement of durable resistance in grapevine.