Polyploidy in wild blackberries (Rubus spp L.)

Number of chromosomes is important for evolutionary studies, phylogenetic, genetic and taxonomic improvement. Due the importance of chromosomes, this research was conducted in order to determine polyploidy on blackberries Rubus adenotrichos Schltdl, R. cymosus Rydb, R. humistratus Steud, R. palmeri Rydb, R. pringlei Rydby, R sapidus Schltdl; Tupi, Kiowa, Tupi x R. sapidus and Kiowa x R. sapidus . Chromosome counting was performed on somatic cells by crushing root tips. Chromosomes were observed and counted in metaphase for each one of specie, polyploidy was determined starting from 1x = 7. Morphological characteristics of each one of specie were based on qualitative descriptors of UPOV 2006. Blackberry showed variability in the number of chromosomal games: Rubus adenotrichos (2n = 2x = 14), R. cymosus (2n = 5x = 35), R. humistratus (2n = 2x = 14), R. palmeri (2n = 4x = 28), R. pringlei (2n = 3x = 21), R. sapidus (2n = 3x = 21); Tupi (2n = 2x = 21), Kiowa (2n = 2x = 28), Tupi x R. sapidus (2n = 2x = 21) and Kiowa x R. sapidus (2n = 2x = 28). Each one of the species presented particular characteristics that characterize them, however, it was not posible to determinate the morphological characteristics associate or define the poly-ploidy in the species analyzed.