【摘要】 为探索深色有隔内生真菌（Dark septate endophytes,DSE）影响富集植物累积重金属镉的作用机制,通过土壤培养和盆栽试验,研究了接种DSE对土壤镉赋存形态和龙葵（Solanum nigrum）积累镉特性的影响。结果表明,接种DSE后土壤中交换态Cd和铁锰氧化态Cd含量显著降低,而碳酸盐结合态、有机结合态和残渣态Cd含量显著增加（P <0.05）;Cd²⁺胁迫下,DSE菌株NBC8-7能在龙葵根内良好定殖,增加了龙葵生物量;与未接种DSE处理相比,不同浓度Cd²⁺（5、10、15 mg/kg）处理下龙葵地上部Cd含量分别提高了37.26%、18.99%和22.54%,地下部Cd含量分别降低了5.19%、5.23%和2.82%;富集系数减小值在0.04～0.09范围内,转运系数增幅在0.18～1.14范围内。综上,接种DSE使土壤重金属Cd由活性较强形态向稳态转化;镉胁迫下,DSE与富集植物龙葵形成联合修复体系,显示了DSE对龙葵修复镉污染土壤的强化效应。更多还原

【Abstract】 To explore the mechanism of dark septate endophytes（DSE） affecting the accumulation of heavy metal cadmium（Cd）in accumulator plants, the paper mainly discussed the effects of DSE on cadmium（Cd）transformation in soil and the accumulation of heavy metal cadmium in Solanum nigrum by soil incubation and pot experiments. The results showed that the contents of the exchangeable fraction and Fe-Mn oxides fraction of Cd significantly decreased, while the contents of carbonates fraction, organic fraction and residual fraction of Cd significantly increased after DSE inoculation（P<0.05）. Under the stress of Cd²⁺, strain NBC8-7 colonized well in the roots of Solanum nigrum. Compared with the treatment without DSE inoculation, the Cd contents in aboveground of Solanum nigrum plants under different application rates of Cd²⁺ at 5 mg/kg, 10 mg/kg, and 15 mg/kg increased by 37.26%, 18.99% and 22.54%, respectively, however, the Cd contents in underground decreased by 5.19%, 5.23% and 2.82%, respectively. The bioaccumulation factor decreased in the range of 0.04-0.09, and the translocation factor increased by 0.18-1.14. In conclusion, the heavy metal Cd in soil was transformed from a highly active form to a stable state by DSE inoculation. Under the stress of cadmium, the combination of DSE and the heavy metal enrichment plant showed that DSE had a significant effect on the remediation of soils contaminated by cadmium.更多还原