Harpins are proteins produced by plant pathogenic bacteria;they induce hypersensitive response in non-host plants. The possibility of harpin induced resistance was investigated in muskmelons, and the physiological mechanism was studied in this paper.1. Harpin did not demonstrate any fungicide effect in vitro. The effect of postharvest dipping with different concentrations of harpin was studied in two Hami melons cultivars (cvs. New Queen and 8601). A concentration at 90 mg/L was the most effective treatment...