防落素对保护地甜瓜叶片生理指标和果实品质的影响

以‘新盛玉’甜瓜为接穗，‘甜砧一号’为砧木，通过田间试验，研究不同浓度防落素处理对保护地甜瓜叶片生理指标和果实品质的影响。结果表明，不同浓度防落素处理表现有差异；随着防落素处理浓度的增加，叶绿素a、叶绿素b、叶绿素和可溶性蛋白含量均呈现出先升后降趋势，以20 mg/L处理含量最高； POD、SOD、CAT和PPO活性均呈现先升后降趋势，以20 mg/L处理活性最高；MDA含量呈先降后升趋势，以20 mg/L处理含量最低；防落素处理提高了果实蔗糖、还原糖含量，降低了果实VC、粗纤维含量。叶片生理指标可作为确定甜瓜生产上应用防落素的参考依据之一。

IInfluence of PCPA on Physiological Indicators of Leaves and Fruit Quality on Muskmelon in Protected Field

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.