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Phylogeny of the Coneflowers and Relatives (Heliantheae: Asteraceae) Based on Nuclear rDNA Internal Transcribed Spacer (ITS) Sequences and Chlorplast DNA Restriction Site Data
TLDR
Results of parsimony analysis of the rDNA dataset uphold the hypothesis from an earlier cpDNA restriction site study that Echinacea is not closely related to the other three genera of coneflowers and suggest that bioprospectors might usefully search among taxa of Zinniinae for bioactive substances similar to the immune stimulants of E Chinacea. Expand
PHYLOGENY OF SUBFAMILY EPIDENDROIDEAE (ORCHIDACEAE) INFERRED FROM NDHF CHLOROPLAST GENE SEQUENCES
TLDR
Trees from both parsimony and maximum likelihood methods suggest that subfamily Epidendroideae is monophyletic, with Listera (Neottieae) as sister, and multiple deletions and frameshifts suggest that ndhF may be a pseudogene, in at least some orchid taxa. Expand
Phylogenetic evaluation of Xylothamia, Gundlachia, and related genera (Asteraceae, Astereae) based on ETS and ITS nrDNA sequence data.
TLDR
The present 3' ETS and ITS nrDNA gene phylogenies yielded the unexpected result that Xylothamia is polyphyletic, which means species within its circumscription are placed into two well-supported evolutionary lineages with other genera of Astereae. Expand
Antimycobacterial crude plant extracts from South, Central, and North America.
TLDR
Two-hundred and thirty crude organic extracts from 118 plant species distributed among 10 families were evaluated for anti-mycobacterial activity and the most active plant species (100% inhibition) were Borrichia frutescens, Solidago arguta, and Inula helenium against M. tuberculosis and M. avium. Expand
Floral initiation and early development in Erigeron philadelphicus (Asteraceae)
TLDR
A comparative study of inflorescence and floral ontogeny of members of the Asteraceae is under way, and results from Erigeron philadelphicus are presented. Expand
Sesquiterpene lactones from Calea leptocephala
Abstract Chemical analysis of Calea megacephala yielded two new sesquiterpene lactones. The new compounds represent a heliangolide, desacylisovalerylheliangine, and the ternifolin derivativeExpand
Germacranolides, calbertolides A, B and C, from Calea berteriana
Abstract The isolation and structure elucidation of two germacranolides, calbertolides A and B, and a heliangolide, calbertolide C, from Calea berteriana are reported. The structures of the newExpand
A phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)
TLDR
This cladistic analysis suggests that Pleurothallis is not a natural genus and, perhaps may be divided into several discrete genera. Expand
Phylogenetics and taxonomy of the New World leafy spurges, Euphorbia section Tithymalus (Euphorbiaceae)
TLDR
The results indicate that the New World species of section Tithymalus form a clade that is sister to the widespread, weedy E. peplus, and that the annual habit probably evolved in the ancestor of E.′peplus and the NewWorld clade, with a subsequent reversal to the perennial habit. Expand
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