Abstract:

The effects of different concentrations of PCPA on physiological indicators of leaves and fruit quality on grafted ‘Xinshengyu’ muskmelon (‘Tianzhen-1’ pumpkin as rootstock) in protected field were studied by field experiment. The results showed that there were differences among different concentrations of PCPA treatments. As the concentration of PCPA increased, the contents of chlorophyll a, chlorophyll b, chlorophyll and soluble protein of muskmelon leaves all increased first and decreased later, and those of 20 mg/L treatment were the highest. And the activities of peroxidase(POD), superoxide dismutase(SOD), catalase(CAT) and polyphenol oxidase(PPO) in leaves all increased first and decreased later, and those of 20 mg/L treatment were the highest. The contents of malondialdehyde (MDA) in leaves decreased first and increased later, and that of 20 mg/L treatment was the lowest. PCPA treatments could increase the contents of sucrose and reducing sugar, and decreased the contents of vitamin C and crude fiber in fruit. Accordingly, physiological indicators of leaves could be used as one of the referenced indexes for the application of PCPA in the production of muskmelon.