【摘要】 为了给镉（Cd）污染土壤修复提供具有景观效果的植物材料，该试验采用盆栽方法，研究土壤中不同质量分数(0、200、500 mg·kg^-1)外源镉添加对大花百子莲（Agapanthus praecox ssp. orientalis‘Big Blue’）耐受性和富集特性的影响。结果表明：随着镉质量分数升高，大花百子莲叶片和根部的生物量有所下降，镉质量分数为200 mg·kg^-1时，与对照相比，叶片生物量下降不显著，而根部生物量显著下降。与对照相比，叶片的过氧化氢酶、过氧化物酶、超氧化物歧化酶活性及丙二醛、可溶性蛋白、脯氨酸含量在镉质量分数为500 mg?kg^-1时显著提高，根部相应的指标在镉质量分数为200 mg·kg^-1时显著提高；叶片和根部的可溶性糖含量在镉质量分数为500 mg·kg^-1时显著提高。上述结果说明：大花百子莲对重金属镉有一定的耐受性，根部较叶片对镉胁迫更敏感。500 mg·kg^-1镉胁迫下，叶绿素a、叶绿素b、叶绿素a+b含量、叶绿素a/b、类胡萝卜素含量显著低于对照；除胞间CO₂摩尔分数外，蒸腾速率、光合速率、气孔导度显著低于对照；除非光化学淬灭系数（NPQ）外，最大光化学效率（F_v/F_m）、PSⅡ潜在活性（F_v/F_o）、实际光化学效率（ΦPSⅡ）、光化学淬灭系数（q_P）有所减少，显著低于对照。镉胁迫下，大花百子莲叶片和根部的富集系数小于1，转运系数大于1，不完全符合镉超积累植物标准，但对镉具有很强的富集作用。综上，大花百子莲在镉质量分数低于200 mg·kg^-1时，能通过自身调节来维持正常生长，对镉胁迫具有一定耐受性和富集性，可以作为具有景观效果的植物修复材料，并且大花百子莲叶片和根部的生物量及镉含量4个指标可以作为衡量镉胁迫耐受性的重要指标。更多还原

【Abstract】 To provide plant remediation materials with landscape properties for cadmium（Cd） contaminated soil, the experiment used a potted method to study the effects of different concentrations of exogenous cadmium(0, 200, 500 mg·kg^-1) on the tolerance and enrichment characteristics of Agapanthus praecox ssp. orientalis ‘Big Blue’.The results showed that with the increase of cadmium stress concentration, the biomass of leaves and roots decreased, and when the cadmium concentration was 200 mg·kg^-1, the leaf biomass didn’t decrease significantly compared with the control, while the root biomass decreased significantly compared with the control. The activities of catalase（CAT）, peroxidase（POD）, and superoxide dismutase（SOD） and contents of malondialdehyde（MDA）, soluble protein, proline in leaves significantly increased compared with the control at cadmium concentration of 500 mg·kg^-1, and the corresponding indexes in roots significantly increased at cadmium concentration of 200 mg·kg^-1 compared with the control. The soluble sugar content of leaves and roots significantly increased at a concentration of 500 mg·kg^-1 compared with the control. The results indicated that Agapanthus praecox ssp. orientalis‘ Big Blue’had a certain tolerance to heavy metal cadmium, and the biomass decreased, the malondialdehyde contents increased, and the antioxidant enzyme activities and osmotic regulator contents increased to alleviate the toxicity of cadmium to Agapanthus praecox ssp.orientalis ‘Big Blue’ under high cadmium stress, and the roots were more sensitive to cadmium than the leaves.Chla, Chlb, Chla+b, Chla/b, and carotenoid content showed a downward trend, and the above five indicators were significantly lower than the control when the cadmium concentration was 500 mg·kg^-1. Except for intercellular CO₂ concentration, transpiration rate, photosynthetic rate, and stomatal conductance significantly decreased compared to the control at cadmium concentration of 500 mg·kg^-1. Except for non-photochemical quenching coefficient（NPQ）, the maximum photochemistry efficiency（F_v/F_m）, PSⅡ potential activity（F_v/F_o）, the actual photochemical quantum efficiency（ΦPS Ⅱ ）, photochemical quenching coefficient（q_P） were reduced at the cadmium concentration of 500 mg·kg^-1, which were significantly lower than those of the control. The enrichment coefficients of the leaves and roots of Agapanthus praecox ssp. orientalis‘ Big Blue’ were both less than 1, and the transport coefficients were both greater than 1. Although it didn’t fully meet the standards for cadmium hyperaccumulation plants, it had a strong enrichment effect on cadmium. Overall, it can be used as a plant remediation material with landscape effects,and the biomass and cadmium content of leaves and roots can be used as important indicators of the ability of the tolerance of Agapanthus praecox ssp. orientalis ‘Big Blue’ to cadmium stress.更多还原