Location: Vegetable Crops Research
Title: Extended studies of interspecific relationships of Daucus (Apiaceae) using DNA sequences from ten nuclear orthologsAuthor
Spooner, David | |
Simon, Philipp | |
Ruess, Holly | |
GEOFFRIAU, EMMANUEL - Institute Research Horticulture Seeds | |
ALLENDER, CHARLOTTE - University Of Warwick | |
MARTINEZ FLORES, FERNANDO - Universidad De Alicante |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 8/21/2018 Publication Date: 8/24/2018 Citation: Spooner, D.M., Simon, P.W., Ruess, H.M., Geoffriau, E., Allender, C., Martinez Flores, F. 2018. Extended studies of interspecific relationships of Daucus (Apiaceae) using DNA sequences from ten nuclear orthologs. 39th International Carrot Conference. Madison, Wisconsin. August 21-24, 2018. Interpretive Summary: Technical Abstract: The latest comprehensive taxonomic monograph of Daucus by Sáenz (1981) recognized 21 species; Rubatzky et al. (1999) later estimated 25 species. Recent molecular studies using a variety of plastid and nuclear DNA sequences, however, have been drastically changing our understanding of the ingroup and outgroup relationships of Daucus (e.g., Spalik and Downie, 2007, J. Biogeogr. 34: 2039-2054; Banasiak et al., 2016, Taxon 65: 563-585; Spooner et al., 2017, Amer. J. Bot. 104: 296-312). Banasiak et al. (2016) used DNA sequences from nuclear ribosomal ITS and the three plastid markers (rps16 intron, rpoC1 intron, and rpoB-trnC intergenic spacer) to redefine and expand the genus Daucus to include the following genera and species into its synonymy: Agrocharis Hochst. (4 species), Melanoselinum Hoffm. (1 species), Monizia Lowe (1 species), Pachyctenium Maire & Pamp. (1 species), Pseudorlaya (Murb.) Murb. (2 species), Rouya Coincy (1 species), Tornabenea Parl. (6 species), Athamanta dellacellae E.A.Durand & Barratte, and Cryptotaenia elegans Webb ex Bolle. They made the relevant nomenclatural transfers into Daucus, expanding the genus to contain over 50 species. Arbizu et al. (2014) identified 94 nuclear orthologs in Daucus, constructed a phylogeny, and determined 10 of them to provide essentially the same phylogeny as all 94, paving the way for additional nuclear ortholog studies in carrot. These 10 nuclear orthologs were then successfully used in a focused study of the species boundaries of the D. guttatus complex (Arbizu et al. 2016, Syst. Bot. 41:479-492), which, in concert with data from type specimens (Martínez Flores et al., 2016, Syst. Bot. 41:464-478) determined the species boundaries and proper nomenclature of the species in this group. The focus of the present study is to further expand these studies by adding taxa from areas not examined with these ten nuclear orthologs before; obtained from (1) the Agrocampus Ouest – IRHS, France, (2) the Warwick Crop Centre, England, and (3) an expedition in Spain in 2016. These include D. arcanus, D. durieua, D. gracilis, D. montanus, D. setifolius, Melanoselinum decipiens, Monizia edulis, Pseudorlaya miniscula, Tornabena annua, and T. tenuissima. Relative to prior studies using these markers, D. arcanus is sister to D. pusillus, D. durieua to D. guttatus, D. gracilis, Tornabena annua, and T. tenuissima (along with D. sahariensis) sister to D. carota, Melanoselinum decipiens and Monizia edulis sister to each other and these to a clade containing Pseudorlaya miniscula, P. pumila, and other species containing 2n = 18 chromosomes, D. setifolius to D. crinitus, and D. montanus (a hexaploid) as a possible allopolyploid between D. pusillus and D. glochidiatus. |