XVI International Botanical Congess

The main goal of this research is to reconstruct the intrageneric phylogeny of Primula by using ITS sequences. The resulting phylogeny is used to evaluate proposed sectional classifications and to elucidate the sequence of evolutionary events that led to the current distribution of breeding systems and chromosome numbers in Primula. A pilot study of ITS sequence variation generated a phylogeny that confirmed the monophyly of sections Auricula, Crystallophlomis, and Aleuritia. Sections Armerina, Sikkimensis, and Crystallophlomis, with chromosome number 2n = 22, formed a well supported clade. The tree also supported the sister relationship between the homostylous P. eximia, widespread from Alaska to Siberia, and the heterostylous P. tschuktschorum, a Beringian endemic.