Am. J. Bot. Cross-Journal Searching
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters 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 Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (3)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Eriksen, B.
Right arrow Articles by Fredrikson, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Eriksen, B.
Right arrow Articles by Fredrikson, M.
Agricola
Right arrow Articles by Eriksen, B.
Right arrow Articles by Fredrikson, M.
(American Journal of Botany. 2000;87:642-651.)
© 2000 Botanical Society of America, Inc.

Megagametophyte development in Potentilla nivea (Rosaceae) from northern Swedish Lapland1

Bente Eriksen2,0 and Margit Fredrikson0

0 Botanical Institute, Evolutionary Botany, University of Göteborg, Box 461, SE-405 30 Göteborg, Sweden

ABSTRACT

An investigation of the embryology of Potentilla nivea was carried out using a confocal laser scanning microscope. The crassinucellate nature of the ovule as well as the presence of a multicellular archesporium was confirmed. A "nucellar cap" builds up as the result of mitotic divisions in the parietal cell tissue and the nucellar epidermis. Earlier reports that several mature megagametophytes are present in each ovule was confirmed. The processes of megasporogenesis and megagametogenesis in Potentilla turned out to differ from descriptions in previous reports, and we propose a reinterpretation. Most importantly, the "archesporium" of previous authors is here considered to be parietal cells, whereas the "chalazal cells" are here interpreted as the archesporium. Meioses commonly occur, giving rise to tetrahedral tetrads. Cytologically unreduced megagametophytes arise from generative tissue (archesporial cells or megasporocytes) only and are diplosporous. Apospory does not occur. The megagametophyte is monosporic and five-nucleate; the three antipodal nuclei normally present in eight-nucleate megagametophytes are missing.

Key Words: apospory • crassinucellate • diplospory • embryology • five-nucleate megagametophytes • laser scanning microscopy • multicellular archesporium • Potentilla • Rosaceae • tetrahedral tetrads




This article has been cited by other articles:


Home page
 Am. J. Bot.Home page
K. T. Hansen, R. Elven, and C. Brochmann
Molecules and morphology in concert: tests of some hypotheses in arctic Potentilla (Rosaceae)
Am. J. Botany, October 1, 2000; 87(10): 1466 - 1479.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2000 by the Botanical Society of America, Inc.