Towards resolving the systematics ofCerastiumsubsectionCerastium(Caryophyllaceae): a cytogenetic approach

Abstract

Analyses of mitotic chromosome numbers and nuclear DNA content were performed for 39 populations of 17 perennial Cerastium taxa from south-eastern Europe. The DNA content ranged from 2C = 2.43 to 8.78 pg, revealing four ploidy levels corresponding to 4x (2n = 36), 8x, 12x and 16x. High-polyploid cytotypes with a greater range of ploidy (up to 2n = 144) occur mostly in the central mountainous parts of the Balkan Peninsula. The chromosome number was determined for the first time for C. dinaricum (2n = 36 + 1B), C. decalvans subsp. orbelicum (2n = 36), C. decalvans subsp. glutinosum (2n = 36), C. neoscardicum (2n = 144), C. malyi subsp. serpentini (2n = 144) and C. moesiacum s.s. (2n = 144). New chromosome counts were recorded for C. arvense subsp. strictum (2n = 108), C. banaticum subsp. kosaninii (2n = 36) and C. grandiflorum (2n = 36). For the first time, flow cytometry was used to estimate C values for six species (15 taxonomic entities). The intraspecific variation quotient of C values is high, ranging from 1.003 in C. malyi to 1.306 in C. decalvans subsp. decalvans. The variation in chromosome size among both tetra-and octoploid members of Cerastium is much more prominent than in most other angiosperm polyploid series. Significant genome downsizing after polyploidization was observed in some investigated taxa. Differences in ploidy levels and monoploid genome size values confirm the taxonomic status of C. decalvans subsp. glutinosum and C. decalvans subsp. leontopodium. The results obtained indicate a possible close relationship between C. banaticum and C. grandiflorum, but not C. arvense.

Diversification of Luzula sect. Luzula (Juncaceae) on the Balkan Peninsula – a cytogenetic approach

“…Frajman and Oxelman 2007;Stefanović et al 2008;Frajman and Schneeweiss 2009;Kučera et al 2010;Surina et al 2011;Lakušić et al 2013;Kutnjak et al 2014;Rešetnik et al 2014;Surina et al 2014) as well as cytogenetic studies (e.g. Bogunić et al 2003Bogunić et al , 2011aSiljak-Yakovlev et al 2005, 2010Muratović et al 2010;Sánchez-Jiménez et al 2012;Niketić et al 2013) shows complex diversification patterns in this area.…”

Patterns of cytotype distribution and genome size variation in the genusSesleria Scop. (Poaceae)

“…In spite of its enormous diversity, the Balkan Peninsula has only recently become the focus of studies exploring the evolution of its biota employing molecular and cytogenetic methods (e.g. Frajman & Oxelman, ; Frajman, Eggens & Oxelman, ; Frajman & Schneeweiss, ; Siljak‐Yakovlev et al ., ; Kuzmanović et al ., ; Lakušić et al ., ; Niketić et al ., ; Pustahija et al ., ; Coppi et al ., ; Kutnjak et al ., ; Surina et al ., ).…”

Long neglected diversity in the Accursed Mountains of northern Albania: Cerastium hekuravense is genetically and morphologically divergent from C. dinaricum

“…The AFLP data are inconclusive regarding the relationships of C. dinaricum and C. hekuravense with other tetraploid Cerastium species from the Alps and the Balkans (Niketić et al 2013). It is clear that they do not belong to the C. latifolium aggregate, in which they were included in the past (Jávorka 1921;Niketić 2007).…”

“…Additionally, we included all other species (Online Resource 1) classified within the C. latifolium aggregate (Niketić 2007)-C. carinthiacum (two populations), C. latifolium (two populations) and C. uniflorum Clairv. (one population), as well as the species distributed on the Balkan Peninsula, which include tetraploid populations (Niketić et al 2013 …”

“…Seeds (0.1)1.4-1.9(2.0) mm long and (0.5)1.1-1.6(1.8) mm wide, (0.2)1.0-1.5(1.6) times longer than wide. 2n = 36 + 1 (Niketić et al 2013). Habitat: Usually northerly exposed humid screes and rock crevices mostly in summit areas; the habitat in Slovenia, where it grows on the bottom of a karstic doline with temperature and vegetation inversion, is an exception.…”