楝和梧桐对镉胁迫的生理响应及富集特性  

On Physiological Responses and Accumulation Characteristics of Melia azedarachand Firmiana Platanifolia under Stress of Cd^2+

作　　者：陈瑶[1] 李凌[1] 周强英 黄泽梅 CHEN Yao;LI Ling;ZHOU Qiang-ying;HUANG Ze-mei(School of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China)

机构地区：[1]西南大学园艺园林学院,重庆400715

出　　处：《西南师范大学学报（自然科学版）》2020年第9期66-70,共5页Journal of Southwest China Normal University(Natural Science Edition)

摘　　要：以楝(Melia azedarach)、梧桐(Firmiana platanifolia)为试验材料,采用盆栽试验的方式研究2个树种在不同浓度土壤镉胁迫(轻度1 mg/kg、中度10 mg/kg、重度50 mg/kg)下的耐性及富集能力.结果表明:重度镉胁迫下,楝和梧桐叶片和根系受到明显胁迫,且随时间延长而逐渐缓解.镉胁迫下,楝和梧桐生物量、总叶绿素呈先增后减的趋势,MDA增大,楝SOD活性升高,梧桐SOD活性显著降低.梧桐长期长势优于楝,表现出更强的耐性.楝对镉的累积情况为根系大于地上部,梧桐则表现为地上部大于根部.梧桐的单株镉富集量大于楝,表现出更强的镉富集能力,适用于重度镉污染土壤的植物提取或植物固定.综合来看,梧桐具备更强的土壤镉修复潜力.Taking Melia azedarach and Firmiana platanifolia as experimental materials,the growth physiological responses,absorption and accumulation characteristics of Cd of the two species under different Cd concentration(mild 1 mg/kg,moderate 10 mg/kg,severe 50 mg/kg)have been investigated by pot experiment.The results show that the leaves and roots of the two species showed obvious signs of persecution under severe Cd stress,which was spontaneous remission with time.The biomass,total chlorophyll of the two species first increased and then decreased under Cd^2+stress,with MDA content increasing,the SOD activity of Melia azedarachincreasing and the SOD activity of Firmiana platanifolia decreasing.Combined,Firmiana platanifolia was more tolerant in long term under Cd^2+stress.The Cd^2+accumulation was in an order of root>the overground parts in Melia azedarach and of the overground parts>root in Firmiana platanifolia.The Cd^2+average enrichment of single plants of Firmiana platanifolia was higher than that of Melia azedarach.The results show that Firmiana platanifolia has greater Cd^2+enrichment abilityand it is more suitabe for phytoextraction of heavy Cd contaminated soil.Taken together,Firmiana platanifolia has a greater potential for remediation of Cd contaminated soil than Melia azedarach.

关 键 词：楝 梧桐 镉 生理响应 富集特性 

分 类 号：S718.43[农业科学—林学]