• 中文
    • English
  • English 
    • 中文
    • English
  • Login
View Item 
  •   DSpace Home
  • 生命科学学院
  • 生命科学-已发表论文
  • View Item
  •   DSpace Home
  • 生命科学学院
  • 生命科学-已发表论文
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Low-molecular-weight organic acids exuded by Mangrove (Kandelia candel (L.) Druce) roots and their effect on cadmium species change in the rhizosphere

Thumbnail
Full Text
A novel ansamycin, naphthomycin K from Streptomyces sp..htm (413bytes)
Date
2007
Author
Lu Haoliang
卢豪良
Yan Chongling
严重玲
Liu Jingchun
刘景春
Collections
  • 生命科学-已发表论文 [5901]
Show full item record
Abstract
Cadmium (Cd) accumulation has been found in large areas of estuaries due to emissions from municipal waste incinerators, car exhausts, residues from metalliferous mining and the smelting industry, and the use of sludge or urban composts, pesticides and fertilizers. In these areas, mangroves have been observed to possess a tolerance to high levels of Cd and it is hypothesized that low-molecular-weight organic acids (LMWOAs) produced at the soil-root interface (rhizosphere) may play an important role in the availability of Cd to these plants. Changes in both LMWOAs and Cd bioavailability, directly or indirectly related to the Cd stress were studied in the laboratory. A rhizobox technique was used for 6 months under growth in air-conditioned greenhouse with natural illumination and the relative humidity of 85%, the temperature ranging from 26 to 32 degrees C, in increasing Cd concentration stress conditions (0, 5, 10, 20, 30, 40 and 50 ppm). Six-month-old Kandelia candel (L.) Druce seedlings which grown in the rhizoboxes were selected to examine their root exudates. The results showed that monocarboxylic acids (formic, acetic, lactic, butyric and propionic acids), and di- and tricarbonxylic acids (maleic, fumaric, citric and L-tartaric acids) were found in root exudates. Citric, lactic and acetic acids being dominant took up 76.85-97.87% of the total LMWOAs in root exudations. Fumaric acid was only found where mangroves were growing on 20 ppm Cd. Root exudates reduced pH by 0.2-0.5 pH units in the rhizosphere compare to the bulk soil. The proportion of exchangeable Cd and Cd bound to carbonate had a positive correlation to total LMWOAs in the rhizosphere soil. Root exudates induced changes in soil Cd species under control conditions, consisting of lower exchangeable Cd compared with increasing stress. Results indicate that the measurement of LMWOAs may be included as early biomarkers in a plant bioassay to assess the phytotoxicity of Cd-contaminated soils on mangrove plants. (C) 2007 Elsevier B.V. All rights reserved.
Citation
Environmental and Experimental Botany,Volume 61, Issue 2, November 2007, Pages 159-166
URI
http://dx.doi.org/doi:10.1016/j.envexpbot.2007.05.007
https://dspace.xmu.edu.cn/handle/2288/10502

copyright © 2002-2016  Duraspace  Theme by @mire  厦门大学图书馆  
About | Policies
 

 

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

LoginRegister

copyright © 2002-2016  Duraspace  Theme by @mire  厦门大学图书馆  
About | Policies