Am. J. Bot.
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 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 (8)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Merckx, V.
Right arrow Articles by Smets, E.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Merckx, V.
Right arrow Articles by Smets, E.
Agricola
Right arrow Articles by Merckx, V.
Right arrow Articles by Smets, E.
(American Journal of Botany. 2006;93:1684-1698.)
© 2006 Botanical Society of America, Inc.

Systematics and Phytogeography

Phylogeny and evolution of Burmanniaceae (Dioscoreales) based on nuclear and mitochondrial data1

Vincent Merckx5, Peter Schols, Hiltje Maas-van de Kamer, Paul Maas, Suzy Huysmans and Erik Smets

2Laboratory of Plant Systematics, K.U. Leuven, Kasteelpark Arenberg 31, BE-3001 Leuven, Belgium; 3National Herbarium of the Netherlands, Utrecht University Branch, Heidelberglaan 2, NL-3584 CS Utrecht, the Netherlands; and 4National Herbarium of the Netherlands, Leiden University Branch, P.O. Box 9514, NL-2300 RA Leiden, the Netherlands

ABSTRACT

The mycoheterotrophic Burmanniaceae are one of the three families currently recognized in the order Dioscoreales. Phylogenetic inference using nucleotide sequences of the nuclear 18S rDNA region and the mitochondrial nad1 b-c intron revealed two well-supported, major lineages within the family, corresponding to the two tribes recognized in the family: Burmannieae and Thismieae. All data supported a strong relationship between Thismieae and Tacca (Dioscoreaceae) making both Burmanniaceae and Dioscoreaceae polyphyletic. The three largest Burmanniaceae genera, Burmannia, Gymnosiphon, and Thismia, are paraphyletic. The splitting of Burmanniaceae into Burmannieae and Thismieae indicates two independent origins of mycoheterotrophy and correlated loss of chlorophyll in Dioscoreales. In the genus Burmannia, in which many species still contain chlorophyll, the achlorophyllous species are nested in between the autotrophic species, suggesting many independent changes from autotrophy to heterotrophy or vice versa. A Bayesian relative rates test on the 18S rDNA data showed considerable variation in substitution rates among Burmanniaceae. The substitution rates in all Thismieae and many Burmannieae are significantly faster than in Dioscoreaceae, but there seems to be no correlation between rate increases and the loss of photosynthesis.

Key Words: 18S rDNA • Burmanniaceae • Dioscoreales • molecular phylogeny • mycoheterotrophy • nad1 b-c intron • Thismiaceae




This article has been cited by other articles:


Home page
 Proc R Soc BHome page
V. Merckx and M. I Bidartondo
Breakdown and delayed cospeciation in the arbuscular mycorrhizal mutualism
Proc R Soc B, May 7, 2008; 275(1638): 1029 - 1035.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2006 by the Botanical Society of America, Inc.