Phylogeny and Phytogeography of Eupatorium (Eupatorieae, Asteraceae): Insights from Sequence Data of the nrDNA ITS Regions and cpDNA RFLP

Abstract

The relationships of eastern North American-eastern Asian-European disjuncts in the genus Eupatorium were examined by sequencing the internal transcribed spacers (ITS) of nuclear ribosomal DNA and restriction site analysis of chloroplast DNA. Molecular data provided strong evidence that (1) this genus originated in North America, (2) the genus diverged into three morphological species groups, €utm&ium, T-aganthes and Uncasia in North America, and (3) one of the North American Uncasia lineages migrated into temperate Europe and eastern Asia over the Bering land bridge. The estimated divergence times support a late Miocene to early Pliocene migration from North America to Eurasia via the Bering land bridge. A European species was sister to all of the eastern Asian species examined. The disjunct distribution pattern of the genus Eupatorium is incongruent with the classical Arcto-Tertiary geoflora concept.

Sesquiterpenoids Isolated from Eupatorium glehnii. Isolation of Guaiaglehnin A, Structure Revision of Hiyodorilactone B, and Genetic Comparison

“…All three samples were identical in the case of ITS1 and ITS2. The results were different from those of Ito et al 34) in that one C was inserted in the ribosomal 18S subunit region and four bases (T192C, C197T, C203T, C207T) were different in the ITS2 region. These data indicate that there is no diversity in the base sequences of the three samples of E. glehnii, but that there is diversity in the chemical constituents.…”

Tropical and Temperate: Evolutionary History of Páramo Flora

“…Moreover, biogeographic events are spatially and temporally scale-dependent, and similar general patterns may represent different individual histories (Ito et al, 2000;Comes & Kadereit, 2003). A distinction must be made between arrivals in the Andes before and after suitable alpine habitats were available.…”

“…Introduced taxa are excluded. Data extracted from Hedberg (1957); van Royen (1980-83); Luteyn (1999); , with an unpublished update for the Afroalpine flora (Hedberg & Hedberg, unpublished) conflict with processes (Hedberg, 1965;Cleef, 1979;Ito et al, 2000;Sklenář & Balslev, 2007). The majority of species of Halenia, for instance, occur in páramos of the northern Andes (Allen, 1933;Luteyn, 1999), but a molecular phylogeny of the genus shows that high species richness of Halenia in the Andes resulted from rapid speciation following repeated immigrations from Central America .…”

Compositae

“…The results of the studies by Schmidt and Schilling (2000) and those of Ito et al (2000b) are in conflict as to the re-recognition of Eupatoriadelphus. Schmidt and Schilling (2000) favour a distinct Eupatoriadelphus (= the 'Eutrochium group') whereas Ito et al (2000b) imply that Eupatorium s.s. can be divided into three 'morphological species groups', one of which is the 'Eutrochium group'.…”