Postharvest oxalic acid treatment induces resistance against pink rot by priming in muskmelon ( Cucumis melo L.) fruit

•Oxalic acid (OA) inhibited pink rot caused by Trichothecium roseum in muskmelon fruit.•OA induced defense-related enzymes, enhanced the contents of antimicrobial compounds, and modulated antioxidant enzymes in muskmelon fruit.•OA strengthened cellular structure based on microscopic and ultrastructural observation.•OA induced disease resistance against T. roseum by priming of defense responses in muskmelon fruit.