Molecular Cytogenetics of Xeranthemum L. and Related Genera (Asteraceae, Cardueae)

Abstract

[EN] Seven representatives of the genera Amphoricarpus, Chardinia, Siebera, and Xeranthemum, all of them closely related as demonstraded by molecular phylogeny, have been studied from a cytogenetic perspective. Morphometrical karyotype parameters were calculated and idiograms obtained. Fluoro- chrome banding was performed with chromomycin A3 to iden- tify GC-rich regions in the chromosomes. Fluorescence in situ hy- bridization allowed us to locate the sites of 18S-5.8S-26S and 5S rDNA. Silver nitrate staining was used to count the number of nucleoli and to detect the active nucleolar organizing regions. Systematic and evolutionary issues are addressed in the light of these data.