摘要
【目的】研究镉污染对香樟幼苗生理生化特性的影响,揭示光合作用等生理特性对香樟镉胁迫的响应机制,探讨香樟的镉耐性及其用于污染修复的潜力与可行性,为镉污染的土壤修复提供数据积累和初步科学依据。【方法】选取1年生香樟为试验材料,采用盆栽试验,设置4个处理,即镉污染浓度分别为0(CK)、1(Cd1)、10(Cd2)和30 mg·kg-1(Cd3),每个处理设5个重复,分别于第0、15、30和60天采样,分析测定不同浓度镉污染条件下香樟叶片光合作用参数以及叶绿素、脯氨酸、可溶性糖、可溶性蛋白、超氧化物歧化酶、过氧化物酶和丙二醛含量。【结果】处理0~15天内,不同浓度镉胁迫下香樟叶片的净光合速率(Pn)无显著变化,培养30天和60天后不同浓度镉处理的Pn均低于对照,且以高浓度Cd3对Pn影响最大,较CK降低约22.33%。不同浓度镉处理下香樟叶绿素含量均降低,降低程度与镉浓度有关。不同浓度镉处理的香樟叶片脯氨酸、可溶性糖和可溶性蛋白含量均增加,Cd3的最高。处理30天和60天后,中高浓度镉处理的超氧化物歧化酶活性显著高于CK和低浓度镉处理;过氧化物酶活性随着镉污染时间及浓度增加而上升;Cd2和Cd3的丙二醛增加显著。【结论】香樟的光合作用参数、渗透调节物质及抗氧化酶等生理生化特性指标与镉浓度和培养时间密切相关,不同浓度镉处理的香樟光合生理特征反映出其具有一定的耐镉性,具备修复重金属污染土壤的潜在价值。
【Objective】In this study,the effect of different concentrations of cadmium pollution on physiological and biochemical characteristics of Cinnamomum camphora seedlings was investigated,which aims to reveal the response mechanism of photosynthetic and other physiological characteristics of C.camphora under cadmium stress,so as to provide data accumulation and scientific basis for the remediation of contaminated soil.【Method】In this study,an indoor pot experiment was conducted with one-year-old C.camphora seedlings that were subjected to 4 treatments of different contents of cadmium in contaminated soil,including 0 mg·kg-1(CK),1 mg·kg-1(Cd1),10 mg·kg-1(Cd2)and 30 mg·kg-1(Cd3),and each treatment had 5 replicates.Samples were collected and analyzed on days 0,15,30,and 60.The photosynthetic characteristics parameters,the contents of chlorophyll,proline,soluble sugar,soluble protein,malondialdehyde(MDA),and the activities of superoxide dismutase(SOD)and peroxidase(POD)of C.camphora seedlings were tested to explore the tolerance of C.camphora to cadmium and its potential and feasibility for phytoremediation.【Result】The net photosynthetic rate(Pn)of C.camphora leaves did not change significantly under different concentrations of cadmium pollution in 0-15 days.Pn of the seedlings treated with contaminated soil for 30 days and 60 days was lower than that of the control,and Pn of seedlings treated with high Cd2+concentration(Cd3)was the lowest with an average deceases of approximate 22.33%compared with that of the control.In addition,the content of chlorophyll in C.camphora under different concentrations of cadmium contaminated soils decreased,and chlorophyll in medium and high concentrations of cadmium(Cd2 and Cd3)significantly reduced.The content of proline(Pro),soluble sugar and soluble protein in C.camphora leaves was increased by cadmium pollution of different concentrations,and the content was the highest under high concentration Cd2+stress(Cd3).After 30 days and 60 days,the activity of SOD in medium and high concentration cadmium treatment(Cd2 and Cd3)was significantly higher than that in the control as well as low concentration cadmium stress.During the whole treatment period,POD activity increased with the pollution time and the cadmium concentration.However,the medium and high concentration cadmium stress had a significant effect on the increase of MDA content.【Conclusion】The results suggest physiological and biochemical indexes of C.camphora,such as the photosynthesis parameters,osmotic adjustment substances and antioxidant protective enzymes,are closely related to stress time and pollution concentration.But,C.camphora seedlings grow well under different concentrations of cadmium stress,reflecting that C.camphora has strong cadmium tolerance and thus has potential value for remediation of heavy metal contaminated soil.
作者
周际海
程坤
郜茹茹
段洪浪
濮海燕
金志农
Zhou Jihai;Cheng Kun;Gao Ruru;Duan Honglang;Pu Haiyan;Jin Zhinong(Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology, Nanchang Institute of Technology, Nanchang 330099;Anhui Provincial Key Laboratory for the Conservation and Utilization of Important Biological Resources,College of Life Sciences,Anhui Normal University,Wuhu 241000)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2020年第6期193-201,共9页
Scientia Silvae Sinicae
基金
江西省教育厅科学技术研究项目重点项目(GJJ180921)
江西省重点研发计划重点项目(20171ACH80016)
国家自然科学基金项目(41661065,31760167)
2019江西省研究生创新专项资金项目(YC2019-S433)。
关键词
香樟
镉污染
光合
生理生化
Cinnamomum camphora
cadmium stress
photosynthesis
physiological and biochemical characteristics