Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow E-letters: Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by SEEL, W. E.
Right arrow Articles by LEE, J. A.
Right arrow Search for Related Content
PubMed
Right arrow Articles by SEEL, W. E.
Right arrow Articles by LEE, J. A.
Agricola
Right arrow Articles by SEEL, W. E.
Right arrow Articles by LEE, J. A.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© 1992 Oxford University Press

RESEARCH-ARTICLE

Effects of Desiccation on some Activated Oxygen Processing Enzymes and Anti-Oxidants in Mosses

W. E. SEEL1,, G. A. F. HENDRY2 and J. A. LEE1

1Department of Environmental Biology, The University Manchester M13 9PL, UK
2NERC Unit of Comparative Plant Ecology, Department of Animal and Plant Sciences, University of Sheffield Sheffield S102TN, UK

To whom correspondence should be addressed

The possibility that desiccation tolerance in mosses may be dependent on an ability to process species of activated oxygen was investigated using the tolerant sand-dune moss Tortula ruraliformis (Besch.) Grout and the sensitive minerotrophic flush species Dicranella palustris (Dicks.) ex. E. F. Warb (D. squarrosa (Starke) Schp.). Mosses were desiccated in low and high irradiance and responses of these plants compared to those of dark-desiccated and hydrated control plants. Both desiccated and undesiccated plants of T. ruraliformis had a higher superoxide dismutase (SOD) activity than D. palustris, but had similar, or lower activities of the chloroplastic H2O2-processing enzymes peroxidase and ascorbate peroxidase. In T. ruraliformis, desiccation in both light and dark led to a significant increase in SOD activity, but did not consistently stimulate the activities of peroxidase and ascorbate peroxidase. In D. palustris, desiccation in combination with irradiance led to a decrease in peroxidase activity, but had little affect on the activities of other activated oxygen-processing enzymes. Catalase, an extra-chloroplastic enzyme, was up to 7-fold more active in hydrated T. ruraliformis than in D. palustris, but desiccation resulted in significant decreases in the activity of this enzyme in both species. Regardless of irradiance level, there was a depletion of the anti-oxidant ascorbic acid in both species when desiccated. Only in T. ruraliformis was there a synthesis of {gamma}-tocopherol, and maintenance of {alpha}-tocopherol and glutathione concentrations when desiccated in the light. Activities of the anti-oxidant recycling enzymes, dehydroascorbate reductase and glutathione reductase, were not significantly increased by desiccation in either moss. The idea is advanced that the role of activated oxygen-processing enzymes involved in the removal of chloroplastic hydrogen peroxide may be less important than that of anti-oxidants in the determination of desiccation tolerance.

Key words: Activated oxygen, anti-oxidants, desiccation, superoxide dismutase, mosses


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 J Exp BotHome page
M. C.F. Proctor and N. Smirnoff
Rapid recovery of photosystems on rewetting desiccation-tolerant mosses: chlorophyll fluorescence and inhibitor experiments
J. Exp. Bot., October 1, 2000; 51(351): 1695 - 1704.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.