INVESTIGADORES
CALVIÑO carolina Isabel
congresos y reuniones científicas
Título:
Phylogenetic relationships within Apiaceae subfamily Saniculoideae based on cpDNA trnQ-trnK 5’exon sequences.
Autor/es:
CALVIÑO, C. I., AND DOWNIE, S. R.
Lugar:
Chicago, Illinois, USA
Reunión:
Congreso; Botany and Plant Biology 2007; 2007
Institución organizadora:
American Society of Plant Taxonomists (ASPT) and Botanical Society of America (BSA)
Resumen:
Phylogenetic relationships within subfamily Saniculoideae were estimated using cpDNA trnQ-trnK 5’exon sequences to clarify the circumscription of the subfamily and to assess the monophyly of its constituent genera.  Ninety-one accessions of Apiaceae were examined, including the genera Steganotaenia, Polemanniopsis, and Lichtensteinia which have been traditionally treated in subfamily Apioideae but determined in recent studies to be more closely related to or included within subfamily Saniculoideae.  The trnQ-trnK  region includes two intergenic spacers heretofore underutilized in molecular systematic studies and the rps16 intron.  Analyses of these loci permitted an assessment of the relative utility of these noncoding regions (including the use of indel characters) for phylogenetic study at different hierarchical levels.  The region presents a large number of phylogenetically informative indels that, when analyzed by themselves, yield trees of great resolution and high levels of overall branch support.  When used with nucleotide substitution data, the inclusion of indels in phylogenetic analyses of both combined and partitioned data sets improves resolution of relationships, increases branch support values, and decreases levels of overall homoplasy.  Moreover, the region is useful at a variety of hierchical levels within Apiaceae, given the large number of parsimony informative characters obtained, as well as adequate levels of sequence divergence observed even among congeners.  Intergeneric relationships derived from MP, Bayesian, and ML analyses, as well as from MP analysis of indel data alone, are fully resolved, consistent with one another and well-supported.  We confirm the expansion of subfamily Saniculoideae to include Steganotaenia and Polemanniopsis (as a new tribe) but not Lichtensteinia.  The latter should be maintained within subfamily Apioideae.  Sister group to the new tribe is tribe Saniculeae, redefined to include the genera Actinolema, Alepidea, Arctopus, Astrantia, Eryngium, Petagnaea, and Sanicula.  With the synonymization of Hacquetia into Sanicula, all genera are monophyletic.