中文摘要：

研究了外源甜菜碱（GB）处理对‘雨花2号＇水蜜桃冷害和品质的影响。结果表明,不同浓度（5、10、20 mmol·L~（-1））外源GB处理可有效抑制桃果肉褐变,减轻冷害症状,其中10 mmol·L~（-1）GB处理效果最明显。外源GB处理可减少桃果实冷藏期间细胞膜渗透性增加和丙二醛的积累,抑制多酚氧化酶（PPO）、过氧化物酶（POD）活性。10 mmol·L~（-1）GB处理还能够保持桃果实较高的果肉出汁率、可溶性固形物、总酚和维生素C含量,并且提高DPPH自由基清除率和总还原力。这说明外源GB处理能减轻桃果实冷藏期间冷害发生,保持果实营养品质,具有较好的应用前景。

英文摘要：

The effects of various concentration of glycine betaine（GB 5,10,20 mmol·L~（-1）） treatments on chilling injury and quality of peach fruits（Prunus persica Batsch ＇Yuhua 2＇） during cold storage were investigated.The results showed that various concentrations of GB treatment could reduce internal browning of peach fruit,wherevers 10 mmol·L~（-1） GB treatment had the best effect.Exogenous GB treatment inhibited the increase of electric conductivity and malondialdehyde（MDA） content,and prevented the activities of polyphenol oxidase（PPO） and peroxidase（POD） in cold-stored peach fruits.Moreover,10 mmol·L~（-1） GB treatment maintained the high level of extractable juice,total soluble solids content,total phenolics content and vitamin C content,and enhanced DPPH radical scavenging capability and reducing power in peach fruit during cold storage.These results suggested that exogenous GB treatment could reduce chilling injury and maintain edible quality of cold-stored peach fruits,which had potential application in postharvest industry.