【摘要】 为探究地肤对酸性土壤中重金属镉(Cd)污染的抗性和敏感性，分别在初始土壤pH值6.1(T处理组)、pH值5.0(TS处理组)条件下，设置不同浓度Cd(1.253、1.553、2.153、2.753、4.253和10.253 mg/kg)胁迫盆栽控制试验，研究了2种pH值和不同Cd浓度处理对地肤生理生化指标的影响。结果表明：(1)Cd胁迫对地肤根总长度、总表面积、总体积、平均直径及根尖数影响均不明显，其中1.253～2.753 mg/kg Cd胁迫下的地肤根、茎及全株生物量变化较小，对土壤镉的耐受性较强，且能较好地适应偏酸性土壤环境；T处理组地肤根系生长发育整体上优于TS处理组。(2)土壤镉含量对地肤光合作用的抑制性不明显，但土壤pH值降低会提高地肤叶片光合色素含量。(3)地肤根部SOD、POD活性、MDA含量整体上高于茎部，相同Cd浓度处理下，土壤pH值升高会提高地肤根茎SOD活性，降低MDA含量。地肤的抗氧化酶系统在防御土壤镉污染胁迫方面起到显著保护作用。更多还原

【Abstract】 This study aims to investigate the tolerance and sensitivity of Kochia scoparia (L.) Schrad.to cadmium (Cd) contamination in acid soil.Pot experiments were designed with different Cd concentrations (1.253,1.553,2.153,2.753,4.253,and 10.253 mg/kg)under initial pH 6.1 (T group) and pH 5.0 (TS group) to evaluate the effects of different pH values and Cd concentrations on the physiological and biochemical parameters of K.scoparia.The experiments yielded the following results.(1) Cd stress had insignificant effects on the root length,root surface area,root volume,average root diameter,and root tip number of K.scoparia.The plants exposed to 1.253～2.753 mg/kg Cd showcased mild changes in the root biomass,stem biomass,and whole plant biomass,demonstrating strong tolerance to Cd stress and adaptation to acid soil.The root growth in the T group was better than that in the TS group.(2) Soil Cd stress had slight inhibitory effect on the photosynthesis of K.scoparia,while the decrease in soil pH increased the photosynthetic pigments in the leaves.(3) The root of K.scoparia had higher activities of superoxide dismutase (SOD) and peroxidase (POD) and higher content of malonaldehyde (MDA) than the stem.Under the same Cd concentration,the increase in soil pH enhanced SOD activity and reduced MDA content in the root and stem.The antioxidases of K.scoparia played a significant role in protecting the plant from soil Cd stress.更多还原