1
artículo
Publicado 2014
Enlace
Enlace
•Premise of the study: We explored the utility of multiple nuclear orthologs for the taxonomic resolution of wild and cultivated carrot, Daucus species. •Methods: We studied the phylogeny of 92 accessions of 13 species and two subspecies of Daucus and 15 accessions of related genera (107 accessions total) with DNA sequences of 94 nuclear orthologs. Reiterative analyses examined data of both alleles using ambiguity codes or a single allele with the highest coverage, trimmed vs. untrimmed homopolymers; pure exonic vs. pure intronic data; the use of all 94 markers vs. a reduced subset of markers; and analysis of a concatenated data set vs. a coalescent (species tree) approach. •Key results: Our maximum parsimony and maximum likelihood trees were highly resolved, with 100% bootstrap support for most of the external and many of the internal clades. They resolved multiple accessions of m...
2
artículo
Publicado 2018
Enlace
Enlace
•Premise of the Study: osible ies boundaries of wild and cultivated potatoes are controversial, with osible the taxonomic problems in the cultivated potato clade. We here provide the first in‐depth phylogenetic study of the cultivated potato clade to explore osible causes of these problems. •Methods: We examined 131 diploid accessions, using 12 nuclear orthologs, producing an aligned data set of 14,072 DNA characters, 2171 of which are parsimony‐informative. We analyzed the data to produce phylogenies and perform concordance analysis and goodness‐of‐fit tests. •Key Results: There is good phylogenetic structure in clades traditionally referred to as clade 1+2 (North and Central American diploid potatoes exclusive of Solanum verrucosum), clade 3, and a newly discovered basal clade, but drastically reduced phylogenetic structure in clade 4, the cultivated potato clade. The res...
3
artículo
Publicado 2016
Enlace
Enlace
In a previous study using 94 nuclear orthologs, we reported the species status of the Daucus guttatus complex to be unresolved, partitioned into three clades. In the present study, a subset of ten of these 94 orthologs was used to infer the phylogeny of the D. guttatus complex and related species. A near parallel set of accessions, planted in a common garden, was used for morphological analyses. The molecular trees are highly resolved for most of the clades, grouping accessions of the D. guttatus complex into four clades. Bayesian concordance analysis and a coalescent approach gave slightly different topologies. Morphological data likewise support four taxa in the complex. Moreover, herbarium research from a companion study informs nomenclature for taxa of the complex. We identify these four clades as D. bicolor, D. conchitae, D. guttatus, and D. setulosus; internested in or among these ...
4
artículo
Publicado 2019
Enlace
Enlace
Daucus has traditionally been estimated to comprise 21–25 species, but a recent study expanded the genus to c. 40 species. The present study uses ten nuclear orthologues to examine 125 accessions, including 40 collections of 11 species (D. annuus, D. arcanus, D. decipiens, D. durieua, D. edulis, D. gracilis, D. minusculus, D. montanus, D. pumilus, D. setifolius and D. tenuissimus) newly examined with nuclear orthologues. As in previous nuclear orthologue studies, Daucus resolves into two well-defined clades, and groups different accessions of species together. Maximum likelihood and maximum parsimony analyses provide concordant results, but SVD quartets reveals many areas of disagreement of species within these two major clades. With maximum likelihood and maximum parsimony analyses Daucus montanus (hexaploid) is resolved as an allopolyploid between D. pusillus (diploid) and D. glochid...