Location: Vegetable Crops Research
Title: Subspecies variation of Daucus carota (Apiaceae) using genotyping-by-sequencingAuthor
Spooner, David | |
MAARTINEZ FLORES, FERNANDO - Universidad De Alicante | |
Simon, Philipp | |
Ruess, Holly | |
REITSMA, KATHLEEN - Iowa State University | |
GEOFFRIAU, EMMANUEL - Institute Research Horticulture Seeds | |
ALLENDER, CHARLOTTE - University Of Warwick | |
MEZGHANI, NAJLA - National Bank Of Genes |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 8/21/2018 Publication Date: 8/24/2018 Citation: Spooner, D.M., Maartinez Flores, F., Simon, P.W., Ruess, H.M., Reitsma, K., Geoffriau, E., Allender, C., Mezghani, N. 2018. Subspecies variation of Daucus carota (Apiaceae) using genotyping-by-sequencing. 39th International Carrot Conference. August 21-24, 2018. Madison, Wisconsin. p. 16. Interpretive Summary: Technical Abstract: Daucus carota is widely distributed worldwide. Its taxonomy is complex with quite variant interpretations of the number of infraspecific taxa, with the greatest problems in the D. carota complex, here defined to include all taxa with 2n = 18 chromosomes. We here principally focus on a distinctive phenotypic group of the “gummifer” types, consisting of plants with a relatively short stature, thick, broad leaf segments, and usually flat or convex fruiting umbels, distributed in the coastal regions of the central and western Mediterranean. We analyze 297 accessions, including 109 accessions of critical germplasm from areas not examined before, obtained from genebanks in England, France, and an expedition in Spain, including the Mediterranean and Atlantic coasts, and Balearic Islands, where much subspecies variation occurs. Genotyping-by-sequencing (GBS) identified 29,041 filtered SNPs. Maximum Likelihood and Structure analysis identified four or five taxonomically and geographically associated groups/clades. Most notably, the gummifer morphotypes co-occur with members of subspecies carota and subsp. maximus in four of these groups (Western Europe, Southern Europe and Balearic Islands, Iberian Peninsula and Morocco, Tunisia), suggesting parallel evolution of the former in maritime environments. The 18-chromosome species D. gracilis (N Africa) and Tornabenea annua and T. tenuissima (Cape Verde) fall firmly within the D. carota clade, forcing a reconsideration of their possible classification as subspecies of D. carota. |