Phylogeny of Rubus (Rosaceae) based on nuclear ribosomal DNA internal transcribed spacer region sequences

We used nuclear ribosomal DNA internal transcribed spacer region (ITS 1 - 5 .8S - ITS 2; ITS) sequences to generate the first phylogeny of Rubus based on a large, molecular data set. We sampled 57 taxa including 20 species of subgenus Rubus (blackberries), one to seven species from each of the remain ing 11 subgenera, and the monotypic and closely related Dalibarda. In Rubus , ITS sequences are most informative among subgenera, and variability is lo w between closely related species. Parsimony analysis indicates that Rubus plus Dalibarda form a strongly supported clade, and D. repens may nest with in Rubus. Of the subgenera with more than one species sampled, only subgenu s Orobatus appears monophyletic. Three large clades are strongly supported: one contains all sampled species of nine of the 12 subgenera; another incl udes extreme Southern Hemisphere species of subgenera Comaropsis, Dalibarda , and Lampobatus; and a third clade consists of subgenus Rubus plus R. alpi nus of subgenus Lampobatus. Rubus ursinus appears to be a hybrid between a close relative of R. macraei (subgenus Idaeobatus, raspberries) and an unid entified subgenus Rubus species. ITS sequences are generally consistent wit h biogeography and ploidy, but traditionally important morphological charac ters, such as stem armature and leaf type, appear to have limited phylogene tic value in Rubus.