Kenaf ( Hibiscus cannabinus) is characterized by rapid-growth, large-biomass, strong-resistance and wide-adaptability.Kenaf is expected to be applicable to treat widespread contamina-tion by heavy metal, not only for the remediation of soil pollution, but also for high economic benefits.In this study, a hydroponic experiment was conducted to investigate the physiological mechanism of kenaf in response to cadmium (Cd) stress with different concentrations (10, 50, 100, 150 and 200 μM) and different treatment time points (1, 2, 3, 4, 5 and 6 d).China Kenaf No.13 was treated with different concentrations of Cd.The results showed that the contents of MDA and AsA in the kenaf seedlings had positive correlations with stress time and Cd concentration which were compared with the control.The content of GSH increased with Cd stress at lower concentration, while first increased and then decreased with the treatment of 150 μM or 200 μM Cd.The activity of SOD and POD increased at beginning and then decreased at lower concentrations.With the treatment of 200 μM Cd, SOD and POD activity de-creased with the stress time increasing.POD activity showed the same phenomena as the treatment of 150μM Cd.Under the low concentration of Cd stress, the activity of antioxidant enzymes and the content of antioxidant substances were enhanced in plants aimed at improving their tolerance to Cd stress.In con-clusion, the changes of the AsA and GSH content and the antioxidant enzyme activity might play an im-portant physiological role to resist damage by Cd stress.%红麻具有生长迅速、生物量大、抗重金属能力强以及适应性广等特点，并且红麻不仅能够治理土壤污染，还可以获得较高的经济效益。本研究以中红麻13号为材料，采用水培技术，研究不同浓度镉胁迫（10、50、100、150和200μM）在不同处理时间（1、2、3、4、5和6天）下对红麻幼苗根系的膜质过氧化，非酶抗氧化物质含量及抗氧化酶活性的影响。结果表明红麻幼根丙二醛、AsA含量与胁迫时间和镉浓度呈现正相关。 GSH含量在较低镉浓度下随镉胁迫的时间延长呈上升趋势，而150μM和200μM镉处理下，GSH含量随时间的延长先增加后减少。 SOD和POD活性在较低浓度下都随镉胁迫时间的延长呈先增加后减少的趋势，而200μM镉处理下的SOD活性和在150μM与200μM镉处理下POD活性均随镉胁迫时间的延长呈减少趋势。在较低浓度镉胁迫下，植株通过提高体内的抗氧化保护酶的活性以及合成AsA和GSH等非酶抗氧化物质来抵御镉胁迫，在一定程度上缓解了镉胁迫的伤害。综上所述， AsA和GSH含量及抗氧化酶活性的变化可能是红麻抵御镉毒害与抗性的重要生理基础。
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