球果蔊菜脯氨酸的积累及与Cd耐性的关系

采用盆栽方法,以风花菜(Rorippa islandica)为对照植物,研究Cd超积累植物球果蔊菜Rorippa globosa (Turcz.) Thell.]脯氨酸的积累、丙二醛含量、生物量及叶绿素含量的变化,及其与Cd生物积累的关系.结果显示,Cd处理能明显促进2种植物体内脯氨酸的积累,当土壤中Cd浓度≤25μg/g时,球果蔊菜叶片脯氨酸的积累效应尤为显著;此时叶片生物量、叶绿素及丙二醛含量与对照相比均无显著差异,表明其叶片脯氨酸的积累在一定程度上可缓解Cd胁迫造成的氧化损伤.相关分析表明,球果蔊菜根系脯氨酸可指示球果蔊菜根系中Cd的积累.

Cadmium tolerance and proline accumulation in Rorippa globosa (Turcz.) Thell

Changes in the biomass, contents of malondialdehyde (MDA), chlorophyll and free proline in the Cd-hyperaccumulator Rorippa globosa (Turcz.) Thell., in particular, the relationships of free proline with Cd accumulation were investigated using pot-culture experiments and compared with a closely related species Rorippa islandica. Application of Cd significantly increased the content of free proline in both R. globosa and R. islandica. There was a significant increase in the level of free proline in leaves of R. globosa treated with 10 and 25μg/g Cd. Moreover, there were no change in biomass of R. globosa leaves, the level of MDA and the content of chlorophyll compared with the control. It could be thus suggested that free proline might play an important role against oxidative stress caused by Cd. The results of the correlation analysis indicated that free proline in roots of R. globosa and in whole tissues of R. islandica might act as the indication of Cd hyperaccumulation.