Intergeneric relationships within the subfamily Rosoideae (Rosaceae) with emphasis on Rubus L.

Abstract

The genus Rubus belongs to the Rose family, and is currently placed in the supertribe Rosodae, of the subfamily Rosoideae. Further systematic placement of Rubus has not yet been clarified, although several hypotheses have been suggested. Several studies show that different datasets based on chloroplast and ribosomal nuclear genes were incongruent with respect to the placement of Rubus. To investigate the relationships between Rubus and other genera within Rosoideae, phylogenies of the chloroplast gene matK, the nuclear ribosomal ITS gene and four single copy genes (GAPCP1, GBSSI-1, GBSSI-2 and SbeI) were inferred on specimens from the following tribes: Colurieae, Potentilleae, Roseae, Rubeae, Sanguisorbeae and Ulmarieae. Our ITS data results are congruent with previous chloroplast data, in which Colurieae is the sister to the rest of Rosodae including Rubus. However, according to low copy nuclear genes analyzed here, Rubeae and Colurieae form a clade separate from rest of Rosodae. This leads us to believe that the incongruence may be caused by incomplete lineage sorting.