Cadmium (Cd) pollution has attracted global concern. In the present study, the biochemical mechanisms underlying the amelioration of 24-epibrassinolide (eBL) and abscisic acid (ABA) on Cd tolerance of roots, stems, and leaves in mung bean seedlings were comparatively analyzed. Foliar application of eBL markedly ameliorated the growth of mung bean seedling exposed to 100 μM Cd. eBL alone had no significant effects on the activities of antioxidative enzymes and the contents of glutathione (GSH) and polyphenols in the three organs whereas significantly increased the root, stem, and leaf proline contents on average by 54.9%, 39.9%, and 94.4%, respectively, and leaf malondialdehyde (MDA) content on average by 69.0% compared with the controls. When the plants were exposed to Cd, eBL significantly reversed the Cd-increased root ascorbate peroxidase (APX) and superoxide dismutase (SOD) activities, root polyphenol, proline, and GSH levels, leaf chlorophyll contents, and MDA levels in the three organs. eBL significantly restored the Cd-decreased leaf catalase (CAT) activity and leaf polyphenol levels. These results indicated that eBL played roles in maintaining cellular redox homeostasis and evidently alleviated Cd-caused membrane lipid peroxidation via controlling the activity of antioxidative systems. eBL mediated the differential responses of cellular biochemical processes in the three organs to Cd exposure. Furthermore, a comparative analysis revealed that, under Cd stress, the effects of eBL on the biochemical processes were very similar to those of ABA, suggesting that ABA and eBL improve plant Cd tolerance via some common downstream pathways.

镉 (Cd) 污染已引起全球关注。本研究比较分析了24-表布拉斯内酯（eBL）和脱落酸（ABA）改善绿豆幼苗根、茎和叶对镉耐受性的生化机制。eBL 的叶面施用显着改善了暴露于 100 μM C​​d 的绿豆幼苗的生长。单独使用eBL对三个器官中抗氧化酶的活性和谷胱甘肽（GSH）和多酚的含量没有显着影响，而显着增加根、茎和叶脯氨酸含量平均54.9%、39.9%和94.4% , 和叶丙二醛 (MDA) 含量与对照相比平均增加了 69.0%。当植物暴露于 Cd 时，eBL 显着逆转了三个器官中 Cd 增加的根抗坏血酸过氧化物酶 (APX) 和超氧化物歧化酶 (SOD) 活性、根多酚、脯氨酸和 GSH 水平、叶叶绿素含量和 MDA 水平。eBL 显着恢复了 Cd 降低的叶过氧化氢酶 (CAT) 活性和叶多酚水平。这些结果表明，eBL 在维持细胞氧化还原稳态方面发挥作用，并通过控制抗氧化系统的活性明显减轻 Cd 引起的膜脂过氧化。eBL 介导了三个器官中细胞生化过程对 Cd 暴露的不同反应。此外，比较分析表明，在 Cd 胁迫下，eBL 对生化过程的影响与 ABA 非常相似，