Unique expression of a sporophytic character on the gametophytes of notholaenid ferns (Pteridaceae).

Loading...
Thumbnail Image

Date

2012-06

Journal Title

Journal ISSN

Volume Title

Repository Usage Stats

55
views
19
downloads

Citation Stats

Abstract

PREMISE OF THE STUDY: Not all ferns grow in moist, shaded habitats; some lineages thrive in exposed, seasonally dry environments. Notholaenids are a clade of xeric-adapted ferns commonly characterized by the presence of a waxy exudate, called farina, on the undersides of their leaves. Although some other lineages of cheilanthoid ferns also have farinose sporophytes, previous studies suggested that notholaenids are unique in also producing farina on their gametophytes. For this reason, consistent farina expression across life cycle phases has been proposed as a potential synapomorphy for the genus Notholaena. Recent phylogenetic studies have shown two species with nonfarinose sporophytes to be nested within Notholaena, with a third nonfarinose species well supported as sister to all other notholaenids. This finding raises the question: are the gametophytes of these three species farinose like those of their close relatives, or are they glabrous, consistent with their sporophytes? METHODS: We sowed spores of a diversity of cheilanthoid ferns onto culture media to observe and document whether their gametophytes produced farina. To place these species within a phylogenetic context, we extracted genomic DNA, then amplified and sequenced three plastid loci. The aligned data were analyzed using maximum likelihood to generate a phylogenetic tree. KEY RESULTS: Here we show that notholaenids lacking sporophytic farina also lack farina in the gametophytic phase, and notholaenids with sporophytic farina always display gametophytic farina (with a single exception). Outgroup taxa never displayed gametophytic farina, regardless of whether they displayed farina on their sporophytes. CONCLUSIONS: Notholaenids are unique among ferns in consistently expressing farina across both phases of the life cycle.

Department

Description

Provenance

Citation

Published Version (Please cite this version)

10.3732/ajb.1200049

Publication Info

Johnson, Anne K, Carl J Rothfels, Michael D Windham and Kathleen M Pryer (2012). Unique expression of a sporophytic character on the gametophytes of notholaenid ferns (Pteridaceae). American journal of botany, 99(6). pp. 1118–1124. 10.3732/ajb.1200049 Retrieved from https://hdl.handle.net/10161/21786.

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.

Scholars@Duke

Pryer

Kathleen M. Pryer

Professor of Biology

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.