Karyotypic analysis of different populations of Carthamus tinctorius Linnaeus (Asteraceae)

Abstract. Somatic chromosomes of Carthamus tinctorius L. were analysed. A karyo-type formula for each studied population was formulated. Although all samples have 2n = 24, they could be differentiated by their karyotype formula and quantitative parame-ters of the karyotypes. The chromosomes were assorted into different categories on the basis of arms ratio following Levan et al. (1964). These were further subdivided into dif-ferent types, on the basis of total length of the chromosomes. Based on an evolutionary point of view, variation in total chromosome length without major changes in the karyo-type formula suggests that changes in the amounts of genomic DNA are proportional to the relative length of an each chromosome arm. All samples possessed symmetrical or slightly asymmetrical karyotype. The samples belonging to the same species were showing intra-specifi c or inter-specifi c chromosome polymorphism. This fi nding may provide useful information for Carthamus evolutionary, genetic, and breeding studies. Key words: Asteraceae, Carthamus, karyotype variation