摘要： 本文研究了外源多胺对在低温胁迫下甜瓜幼苗体内DNA、RNA、可溶性蛋白质、超氧物歧化酶（SOD）及细胞质膜透性的影响。结果表明，多胺处理的甜瓜幼苗在低温（2±；1℃）下处理10h后，RNA和DNA含量明显增多，蛋白质的图谱发生显著变化，SOD活性增强，细胞膜的破损渗漏较少，尤以0.4mmol的腐胺处理最为显著。多胺与核酸的相互作用调节了植物体内的代谢过程，与膜的相互作用增强了机体的抗冷性。

关键词: 甜瓜, 腐胺, 抗冷性, 代谢调节

Abstract: The effects of polyamines on the contents of DNA, RNA and soluble proteins, the activity of superoxide dismutase, the permeability of plasma membrane of the melon seedlings were studied under the stress of low temperature.The results indicated that after the seedlings were treated with low temperature (2±1℃ ) for JO hours, the contents of RNA and DNA were significantly increased, the protein map was changed, the activity of SOD was strengthened and the percolation rate of plasma membrane was decreased comparing with control.The effect of the treatment with 0.4mmol putrescinc was the best comparing with other treatments used in this experiment.The metabolic process of melon seedlings was regulated through the interaction between polyamines and nucleic acid, and the plant resistance to cold was increased through the interaction between polyamine and plasma membrane.

Key words: Melon, Putrescine, Cold resistance, Metabolic regulation