中文摘要：

采用水培法,研究了不同质量浓度（10、20、40、60、80、100mg/L）的稀土镨（Pr）对Cd胁迫下水稻根系生理特性的影响,结果表明,在50μmol/LCd胁迫下,水稻根系干重、根系活力、SOD、APX和CAT活性明显降低,与对照相比,分别下降了31.6%、46.1%、23.3%、57.6%、40.1%,POD活性、质膜透性、膜脂过氧化产物MDA和脯氨酸含量显著增加,分别为对照的1.61、2.05、1.82、1.63倍.10～80mg/L的Pr处理对Cd胁迫下水稻根系生长有不同程度的缓解效应,可减轻Cd对根系的伤害,Pr缓解Cd胁迫的作用与提高根系活力、增加脯氨酸含量、降低MDA含量和细胞膜透性、维持SOD、APX和CAT活性有关.Pr处理的最适质量浓度为40mg/L,但100mg/L的Pr处理反而加重Cd胁迫.

英文摘要：

To investigate the alleviated effects of Cd stress on rice roots with Pr treatment,solution culture experiments were conducted to study the effects of different Pr levels （10,20,40,60,80,100 mg/L） on root physiological characteristics of rice （Oryza sativa L.） under Cd stress.The results showed that Cd stress had significant inhibitory effects on root growth.Under Cd stress,the root dry mass,root activities,SOD,APX and CAT activities decreased by 31.6%,46.1%,23.3%,57.6% and 40.1%.However,POD activities,electrolytic leakage,MDA and proline content were significantly higher than those of control,which were 1.61,2.05,1.82,1.63 times respectively.With the treatment of 10～80 mg/L Pr,root growth was reconditioned to different degrees and the damage of Cd toxicity reduced.It proved,by the experiment,that Pr can improve root activities and proline content,reduce cell membrane permeability and MDA content,and keep the activities of SOD,APX and CAT of rice root.By contrast,the optimum concentration of Pr was 40 mg/L.However,under the treatment of 100 mg/L Pr,the toxic effect of C was aggravated.