Survey of chromosome numbers in Rubus (Rosaceae:Rosoideae)

A literature survey was made of chromosome number counts for Rubus species. Numbers are presented for 387 species, representing about 40 percent of the total number, and including 11 of the 12 subgenera. The basic number is universally 7 and ploidy levels include 2x, 3x, 4x, 5x, 6x, 8x, 9x, 10x, 11x, 12x, 14x, and, questionably, 13x and 18x. In a few species, more than one chromosome number has been reported. Attempts were made to provide the currently accepted taxonomic designation for each species as well as the outdated synonyms used in original publications. The objective was to provide a summary of available information on chromosome numbers of Rubus species and to point out the gaps that need to be addressed.