Morphological variability and genetic diversity in Carex buxbaumii and Carex hartmaniorum (Cyperaceae) populations

Abstract

Background Carex buxbaumii and C. hartmaniorum are sister species of the clade Papilliferae within the monophyletic section Racemosae. An unambiguous identification of these species is relatively difficult due to the interspecific continuum of some morphological characters as well as the intraspecific variability. The study was aimed at determining the range of variability, both morphological and genetic, within and between these two closely related and similar species. Methods The sedges were collected during botanical expeditions to Armenia, Estonia, the Netherlands, and Poland. The morphological separation of the two species and their populations was tested using the Discriminant Function Analysis (DFA). The genetic variability of the 19 Carex populations was assessed in the presence of eight Inter Simple Sequence Repeat (ISSR) primers. Results Results of the study indicate a considerable genetic affinity between the two sedge species (mean Si = 0.619). However, the populations of C. hartmaniorum are, morphologically and genetically, more homogenous than the populations of C. buxbaumii. Compared to C. hartmaniorum, C. buxbaumii usually has wider leaf blades, a shorter inflorescence, a lower number of spikes which are shorter, but wider, and longer bracts and utricles. The AMOVA showed a larger variation between the populations of C. buxbaumii, representing 25.65% of the total variation in the taxon. Two populations of C. buxbaumii (from Poland and Estonia) are separated from the remaining populations, both genetically and morphologically; their individuals show shorter utricles and glumes, compared to the typical specimens of C. buxbaumii, and correspond with the morphology of putative infraspecific taxa described by Cajander (var. brevisquamosa and var. confusa). Conclusions The taxonomic status of the putative infraspecific taxa within C. buxbaumii requires further studies throughout the distribution range of C. buxbaumii, addressing habitats, morphology and genetics (including a chromosome count or a combination of different genetic methods), particularly as the variability in C. buxbaumii may be associated with the species’ polyploid origin.

Morphological variability of Carex buekii (Cyperaceae) as a function of soil conditions: a case study of the Central European populations

“…The type of land use (grazing, mowing) may affect plant morphology as well 46 . Sedges growing at sites with poorer light conditions employ a shade avoidance strategy and develop higher culms as an advantage in the relatively strong competition for light 47 . Abnormally developed spikes are frequently observed in dry areas, e.g.…”

Morphological and Genetic Diversity of Schoenoplectiella mucronata (L.) J. Jung & H. K. Choi (Ricefield Bulrush) in Rice

“…inflorescence number (per plant), fresh weight (g) and dry biomass (g) (Tayyar et al, 2003;Więcław et al, 2021). After harvesting, the plants were dried at 70°C for 3 days for dry biomass measurement.…”

“…The genetic similarity matrix is based on Euclidean distances. The Principal Component Analysis (PCA) is relatively objective and provides a reasonable indication of relationships, it was used to confirm the similarity of the grouping obtained with the UPGMA dendrogram (Więcław et al, 2021). The Table 3 illustrates the PC components obtained from the principal component analysis (PCA) results based on the morphological characteristics of S. mucronata populations.…”

Response Patterns of Fen Sedges to a Nutrient Gradient Indicate both Geographic Origin-Specific Genotypic Differences and Phenotypic Plasticity

“…Phenotypic plasticity might therefore be especially advantageous in heterogeneous habitats, such as peatlands. More generally, considerable phenotypic plasticity occurs in different Carex species (Więcław 2017;Więcław et al 2021Więcław et al , 2022, including alpine Carex species, i.e., in species which also live in rather heterogeneous habitats (Schmidt et al 2018). An advantage of increased biomass at higher nutrient levels, as observed in our study, could be higher ability to deal with competition, e.g., for light (Kotowski et al 2006).…”

“…Closely related Carex species -which supposedly have similar ecological niches -tend to not occur at the same sites, whereas sympatric Carex species often occupy well-distinguishable niches (Waterway et al 2016). At the same time, Carex populations of the same species, but from different geographic origins, show local adaptations, for example with regard to their growth and phosphate absorption rates and, more generally, with regard to their realized ecological niches, and can also exhibit morphological differences (Chapin and Chapin 1981;Chapin III and Oechel, 1983;Choler and Michalet 2002;Hájková et al 2008;Więcław et al 2021). While some studies about local adaptations of Carex species are thus available, we lack information about intra-specific adaptations of this fen-dominating genus to differences in nutrient availability.…”