Skip Navigation

This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
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 Similar articles in ISI Web of Science
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (5)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Ungar, I. A.
Right arrow Articles by Khan, M. A.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Ungar, I. A.
Right arrow Articles by Khan, M. A.
Agricola
Right arrow Articles by Ungar, I. A.
Right arrow Articles by Khan, M. A.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Annals of Botany 87: 233-239, 2001
© 2001 Annals of Botany Company

Effect of Bracteoles on Seed Germination and Dispersal of Two Species of Atriplex

Irwin A. Ungar+ and M. Ajmal Khan

Department of Environmental Plant Biology, Ohio University, Athens, Ohio 45701-2979, USA Department of Botany, University of Karachi, Karachi, Pakistan 75270

Received: 28 June 2000 ; Returned for revision: 7 September 2000 . Accepted: 13 October 2000

The influence of bracteoles on the germination response of a salt marsh annual, Atriplex prostrata, and a salt desert perennial, A. griffithii, was determined. Attached bracteoles did not inhibit germination of A. prostrata but completely inhibited germination of A. griffithii seeds. Germination of seeds ofA. griffithii was also somewhat inhibited in the presence of detached bracteoles. The osmotic potential of dissolved substances in water-saturated bracteoles was -4.8 ± 0.05 MPa for A. griffithii and -2.4 ± 0.15 MPa for A. prostrata. Ash content of bracteoles on a dry weight basis was 28.7 ± 0.37% for A. prostrata and 30.0 ± 0.29% for A. griffithii. The presence of relatively high concentrations of dissolved salts in bracteoles may explain the reduced germination of A. griffithii. Germination of seeds of the perennial A. griffithii may also be inhibited mechanically by the presence of persistent bracteoles, whereas the annual A. prostrata has ephemeral bracteoles that may serve to limit germination in the autumn but are not present during the normal spring germination period. Bracteoles could affect the dispersal of seeds by water since some fruiting structures of A. griffithii and A. prostrata are able to float in 1.0% NaCl solutions for 5 and >30 d, respectively, compared with a maximum of 4 and 3 d for seeds without bracteoles. Fruiting structures of A. prostrata floated for longer over a range of salinities than did those ofA. griffithii ; this may play a significant role in the dispersal of this salt marsh species. Copyright 2001 Annals of Botany Company

Atriplex, bracteoles, dispersal, flotation, germination, salinity, temperature


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




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.