Abstract: Rice (Oryza sativa L. cv. W251) was sprayed with 0, 50, 100, 300, 500, 700, 1000 mg/L of choline chloride during seedling stage. One week after spraying, seedlings were treated with low temperature (3-4℃ ) for 48 hours. In comparison with the control, the activities of superoxide dismutase, catalase and peroxidase, and the content of chlorophyll in rice seedling treated with choline chloride were all increased in varying degrees, the level of malondialdehyde in rice seedling and the leakage of electrolytes from rice seedling treated with choline chloride were decreased. The content of bound water was increased, while the content of free water was decreased for rice seedling treated with choline chloride, as a result the level of soluble sugar, proline and soluble protein were increased. The above results indicated that the choline chloride had protective effect on the membrane lipids and increased the level of protective substance for cold-tolerance in rice seedling under chilling stress. The best protective effect was achieved with 300 mg/L of choline chloride treatment.

Key words: choline chloride, cold tolerance, lipid peroxidation, membrane permeability, rice seedling

摘要： 以不同浓度(0、 50、 100、 300、 500、 700、 1000 mg/ L)的氯化胆碱溶液浸种处理和叶面喷施稻苗，在3～4℃低温胁迫下，稻苗的超氧物歧化酶、过氧化氢酶和过氧化物酶等活性均显著地高于对照，其膜脂过氧化产物丙二醛产生量和电解质外渗率均低于对照，叶绿素残存量则高于对照；可溶性糖、可溶性蛋白质和脯氨酸等含量均明显高于对照；故经氯化胆碱处理者，其总含水量与对照间差异虽然不大，但束缚水含量增加而自由水含量减少。上述结果表明氯化胆碱能明显地保护处于低温胁迫下的稻苗的细胞膜系结构和提高其防冷性物质含量，从而增强稻苗的抗冷性。

关键词: 氯化胆碱, 水稻幼苗, 脂质过氧化作用, 膜透性, 抗冷性