Submitted to: Genetic Resources and Crop Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2006
Publication Date: 6/1/2007
Citation: Camadro, E.L., Cauhepe, M.A., Simon, P.W. 2007. Geographical Distribution of Wild Daucus Species in the Natural Grasslands of the Argentinian Pampas . Genetic Resources and Crop Evolution. 54(4):855-863. Interpretive Summary: The conservation of plant genetic resources is of fundamental importance for maintenance and enhancement of agricultural production. Genetic variability is essential for developing new cultivars to cope with adverse factors that are eroding the system, as well as to introduce desirable culinary, nutritional and processing traits, among others. Without genetic variability, the progress from selection is nil, and there is a constant need for a regular introduction of new genetic variation into breeding programs. Carrot is the major vegetable umbellifer cultivated worldwide, and there are three wild related species found in the American continent. In this study we evaluated newly collected wild D. pusillus and wild carrot from the pampas grasslands of two Argentinian provinces. We observed wide variation in both species and distinct differences between them, even though they were growing in the same geographic areas. This research is of interest to carrot breeders and researchers, plant taxonomists, and conservation biologists.
Technical Abstract: For Argentina, three wild carrot species have been described: Daucus montanus Umb. & Bonpl. ex Schult., D. montevidensis Link ex Sprengel and D. pusillus Michx. There is a discrepancy among authors about the distinctive morphological traits of the last two species; thus, it is difficult to ascertain if they belong to different taxons or are actually synonymous. Based on the bibliography and in the search of a paradigmatic site, four collection trips were carried out in 2004 and 2005 in Buenos Aires and Southern Entre Ríos provinces. Populations were sampled at 30 sites, and the macro- and microenvironments and accompanying flora were described. Morphological observations and chromosome counts were carried out in 10 plants/population. Three phenotypes were distinguished: one in 18 populations, with 2n=2x=18, and two in the remaining 12, with 2n=2x=22 and aneusomaty (2n=2x=20, 22). Populations of the first phenotype were assigned to wild D. carota and the rest, tentatively, to D. pusillus (D. montevidensis?), till further evaluations are carried out in test sites to confirm or refute this tentative conclusion.