Karyotypic variability in some species of the genus Chondrilla (Asteraceae)

摘要

Karyotypic variability of plants was evaluated in 17 populations of six species of the genus Chondrilla ( C. ambigua Fisch. , C. brevirostris Fisch, et Mey., C. laticoronata Leonova , C. canescens Kar., Kir., C. juncea , C. pauciflora Ledeb.) in the Astrakhan, Voronezh and Saratov regions, the Republic of Kalmykia, and Western Kazakhstan. It is maintained that C. ambigua is a strict diploid (2n = 2x = 10) species, while its close relative - C. pauciflora - is a strict triploid (2n = 3x = 15) taxon. The research demonstrates that the plants of the apomictic taxa C. brevirostris , C. canescens , C. juncea and C. laticoronata are characterized by the genomic instability in the form of chromosome instability which results in these species’ mixed-ploidy populations.