中文摘要：

以耐Cd性不同的两个水稻品种（秀水63和秀水09）为试验材料,采用溶液培养方法,比较研究不同浓度Cd（0,1,5,10,25,50,100μmol/L）胁迫不同时间后水稻幼苗生长、脯氨酸、丙二醛（MDA）和抗氧化酶活性的变化。结果表明：随Cd胁迫浓度增加和胁迫时间延长,水稻幼苗生长明显受抑,株高和地上部干重增长、叶绿素含量明显下降,且秀水63降幅大于秀水09;处理3 d后,较高浓度Cd（≥50μmol/L）胁迫造成叶片MDA含量明显增加,随着胁迫时间的延长,高于10μmol/LCd胁迫对MDA含量有显著影响,特别是秀水63。叶片脯氨酸含量、SOD、POD活性随Cd胁迫浓度增加和胁迫时间延长呈增加的趋势,且秀水09的增加幅度高于秀水63,而CAT活性表现为先增加后降低,在较高浓度Cd胁迫下（≥25μmol/L）秀水63降幅较大。可见,较高的脯氨酸含量和较强抗氧化酶活性是秀水09耐镉性强于秀水63重要原因之一。

英文摘要：

Different responses of seedlings growth and physiological characteristics in different cadmium-tolerant rice cultivars（Xiushui 63 and Xiushui 09） were studied with a hydroponic experiment under different Cd concentration（0,1,5,10,25,50,100 μmol/L）.The results showed that the growth of rice seedlings was restrained significantly by the increase of Cd concentration and prolonged time.The inhibition rates of height,leaf dry weight and chlorophyll content in Xiushui 63 were greater that those in Xiushui 09.The content of MDA increased observably the stress of high concentration of Cd（≥50 μmol/L） for 3 days.With the prolonged time,Cd high than 10 μmol/L the content of MDA increased signficantly after Cd treatment for 9 days.The content of proline and activities of superoxide dismutase（SOD） and peroxidase（POD） increased under Cd stress.And they were more obvious in Xiushui 09 with the same concentration and the stress time.The activity of catalase（CAT） firstly increased and then decreased as the Cd concentration increased,and it####