XVI International Botanical Congess

Prunus L. (Rosaceae) consists of approximately 200 species and has a controversial taxonomic history. Sequences of the internal transcribed spacer region of nuclear ribosomal DNA were employed to construct the phylogeny of Prunus and Prunoideae. Prunoideae is paraphyletic with Exochoda of the Spiraeoideae nested within. The genus Maddenia of the Prunoideae is nested in Prunus. None of the traditionally recognized subgenera of Prunus is monophyletic. Taxa of the subgenera Lauracerasus and Padus are basal within Prunus. Subgenera Amygdalus and Prunus form a monophyletic group. Evergreen leaves evolved at least twice within Prunus.