Bacterial spot disease is one of the destructive threats to peach production, damaging leaves, weakening tree vigor, and reducing fruit quality. New research reveals how peach plants activate a natural chemical defense to limit this disease. The study shows that infection by Xanthomonas arboricola pv. pruni (Xap) triggers the accumulation of proanthocyanidins (PAs), plant metabolites known for antioxidant and antimicrobial activity. At the center of this response is the transcription factor PpMY