36th International Carrot Conference Abstract

Reassessment of practical species identifications of the USDA Daucus carota germplasm collection: Morphological data

David M. Spooner, Mark P. Widrlechner, Kathleen R. Reitsma, Debra E. Palmquist, Philipp W. Simon

Spooner and Simon - USDA Vegetable Crops Res Unit Madison WI
Widrlechner - Iowa State Univ, Ames IA
Reitsma - North Central Regional Plant Introduction Station Ames IA
Palmquist - USDA Midwest Area Office Peoria IL

The genus Daucus includes about 20 species. The most widespread and economically important species, Daucus carota L., occurs on almost every continent. Cultivated carrot, subsp. sativus, has been selected from wild populations that are extremely diverse, especially in the western Mediterranean. Obligate outcrossing and lack of sexual isolating mechanisms among recognized infraspecific taxa complicate the taxonomy and identification of the wild populations, resulting in widely different interpretations of the number of infraspecific taxa. The US Daucus germplasm collection at the North Central Regional Plant Introduction Station (NCRPIS) in Ames, Iowa conserves about 1370 accessions, with about 1200 of these being D. carota. The purpose of our study was to explore morphological support for eight recognized subspecies of D. carota held at NCRPIS. We measured 36 morphological characters from multiple individuals within each of 155 accessions of D. carota, and the morphologically similar species D. capillifolius, alongside other species for comparison, in an experimental field plot. Within D. carota, multivariate analyses were able to identify only two subspecies, but even these showed great overlap of individual characters. In combination with molecular data and field collections, our goal is to reassess the practical identification of germplasm collections of D. carota.

Last updated Thursday, 25-Jul-2013 11:54:50 CDT