WATSON, LINDA E.1*, HANAA EL-SHAZLY1,2, HANAN SAYED-AHMED3, MICHAEL A. VINCENT1, and ABDELFATTAH BADR1,3. 1Department of Botany, Miami University, Oxford, Ohio, 45056 USA; 2Ains Shams University, Department of Biological and Geological Sciences, Cairo, Egypt; 3Department of Botany, Tanta University, Tanta, Egypt. - Molecular Phylogeny of Old World Trifolium (Fabaceae).
Phylogenies of Trifolium species were constructed using
nucleotide sequence data of the internal transcribed spacers (ITS) of
nuclear ribosomal DNA and chloroplast DNA restriction site data from
PCR-amplified genes and genic regions (rbcL, trnK, and
rpoC1-C2). Biogeography, morphological evolution, and the
existing classification for Trifolium were examined. The genus
Trifolium is strongly supported as monophyletic, however, only
one small section (Chronosemium) is monophyletic, although the
data are in conflict regarding its placement. The two largest sections
of the genus, Sections Lotoidea and Trifolium, are not
supported as monophyletic, as currently circumscribed. Section
Chronosemium is embedded within Section Trifolium and
many members of Section Lotoidea form a basal grade within the
genus. This basal position of Section Lotoidea supports
previously-proposed hypotheses concerning plesiomorphic morphological
characters and a Mediterranean-Mideast biogeographic origin of the
genus.
Key words: Fabaceae, phylogeny, Trifolium