Effect of Carrot Gene Pool
In the present work, carrot accessions originating from various world regions were compared. In particular, the experiment comprised 14 accessions from Europe, 16 from Asia (including five from Japan), four from USA and one from Ethiopia. The classification of carrot accession to either Western or Eastern gene pool, done previously by Baranski et al. [24], was based on the polymorphism of DNA simple sequence repeat loci. For accessions with no molecular assessment available, additional criteria were set to classify them to one of these two types. As orange and white root color are characteristic for Western carrot type, the presence of other color and Asian origin was chosen as criteria to include an accession to Eastern type. Thus Western and Eastern carrot types were finally represented by 17 and 18 accessions, respectively (Online Resource 1). It should be stressed that the lack of clear delimitation between Eastern and Western types depending on the country of carrot origin or root color is the result of an intensive and long lasting breeding in which
materials of various origins were crossed. For example, European materials were used to obtain cultivars in Japan while Japanese cultivars were used as parental populations
in American breeding programs.