A comparison between Carex arenaria L. and Carex ligerica GAY - sedges from the Arenariae group based on leaf characteristics

The purpose of the study was to compare two taxonomically close species of sedges - <i>Carex arenaria</i> and <i>Carex ligerica</i>. The analysis was based on 6 characters of leaves. The populations studied were grown for the period of at least one year under the same conditions in a greenhouse. The results of statistical analysis indicate a distinctive character of each of the studied populations. Furthermore, the results show a higher interpopulational differentiation among <i>C. ligerica</i> populations.

Differentiation between Carex arenaria L. populations at the eastern range margin based on female and male glumes variation

480 spikes from 16 populations of <em>Carex arenaria</em> L. planted in an experimental garden were collected and analysed for 4 female and 4 male glumes each. The characteristic of the interpopulational differentiation on the area of Poland was based on multivariate analysis, Student t-test and the coefficients of variation. The separateness of three populations from the isolated inland stations - 3(Góra), 11 (Tuczno), 15 (Poznań) and individual character of - 2 (Wisełka), 6 (Sobieszewo) from the coast and 9 (Ołobok) from Lower Silesia is shown. The lowest level of variation and in consequence a particular usefulness for taxonomic considerations have two characters - a and a' (length of female and male glumes). The obtained pattern of interpopulational differentiation may be caused by various factors - migration routes on the Polish territory; selection pressures associated with different ecological conditions present in fixed dunes along the Baltic Sea coast and in isolated inland stations, occupied by <em>C. arenaria</em>; reduction of an extensive primary populations to markedly smaller isolated subpopulations.

Variability characteristics and comparison of Carex arenaria L. and Carex ligerica Gay populations based on rhizome characters

The studies included 9 populations of <i>Carex arenaria</i> L. and 7 populations of <i>Carex ligerica</i> Gay, compared with each other on grounds of variability analysis, related to rhizome characters. The sedges reach in the area of Poland their eastern range limits, with isolated populations spread along the range margins. The studied plants were placed in a greenhouse in homogenous conditions,which made possible an analysis of genetic variability in the populations. The obtained results point to the absence of gene flow between the studied species and, thus, to their clearly distinct character. Genetic drift was postulated as one of the causes of the obtained variability pattern.