Pumpkin rootstocks regulate the resistance of grafted cucumbers to powdery mildew through DNA methylation
Cucumber is highly susceptible to powdery mildew (PM), which compromises yield and quality. Grafting onto resistant rootstocks is widely used to improve PM resistance, yet the underlying molecular mechanisms remain unclear. In this study, cucumber scions (Luhuanggua No. 3) were grafted onto two pumpkin inbred rootstocks, nd8 (resistant) and nd4 (susceptible), followed by PM inoculation. Physiological responses, transcriptomic profiles, and DNA methylation changes were examined.