Karyotype analyses of some Tanacetum L. (Asteraceae) taxa

The genus Tanacetum placed in the tribe Anthemideae in the family Asteraceae commonly distributed in temperate zone involving Asia, Europe and North America. It contains more than 150 taxa over the World. The genus is represented by 60 taxa including species, subspecies and varietes in Turkey. In this study, karyotype analysis was carried aut on the following taxa; T. albipannosum Hub.-Mor. & Grierson, T. aucheranum (D C.) Schultz Bip., T. parthenium (L.) Schultz Bip., T. argyrophyllum var. argyrophyllum (C. Koch) Tvzel.Materials used in this study were collected from Trabzon and Gümüşhane cities between the years 2005 ? 2009 in June. The collected species were distinguished from morphological characters and dried through herbarium tecniques. Meristematic root tips and achenes belonging to each taxa were obtained from natural habitats. The achenes were germinated at room temperature. Roots tips were stained in aceto-orcein and permanent slides were prepared. Chromosomes number, complement, measurement, arm ratios and centromere position of each taxa were determined from permanent slides.Consequently, all taxa investigated were found to be diploid taxa with 2n=18 chromosomes. Although investigated species had same chromosome number, there were some differences in chromosome morphologies. Karyotype of the taxa were observed in median, submedian and subterminal choromosomes according to centromer location.