Taxonomic individuality of Leonurus cardiaca and Leonurus quinquelobatus in view of morphological and molecular studies

The main goal of this study was to determine the number and taxonomic rank of taxa belonging to the complex Leonurus cardiaca agg. in Poland. Based on statistical analysis of selected features, two morphological forms of this plant were distinguished. In order to determine their genetic polymorphism and the relationships between them, the nuclear, mitochondrial and chloroplast genomes were analysed with the use of RAPD and PCR–RFLP markers. 39 RAPD primers produced a total of 234 nuclear DNA fragments, of which 128 were polymorphic and distributed almost equally between two forms. It was found that 87 % of the compared pairs of RAPD profiles differ from each other. Five chloroplast and two mitochondrial primer pairs were used to amplify non-coding regions of organelle genomes. Restriction analysis revealed uniformity of mtDNA and occurrence of two cpDNA haplotypes, corresponding to naked and hairy forms of L. cardiaca agg. The obtained results justifies the recognition of these forms as separate species L. cardiaca s. s. L. and L. quinquelobatus Gilib., respectively. The distribution of both species in Poland is given in the paper

Materials to the flora of dandelions (Taraxacum – Asteraceae) in Błażowa (SE Poland)

The paper includes a list of localities of 35 Taraxacum species found in Błażowa town. The species belongs to 3 sections: Borea, Palustria, and Ruderalia. The record of the new species to the Polish flora – Taraxacum clarum Kirschner, Štěpánek et Trávníček – is given. Data were collected from 2011 to 2014

Insights into developmental processes in anthers, ovaries, and ovules of Taraxacum belorussicum (Asteraceae-Cichorioideae) using DIC optics

This study represents the first report on the embryological characteristics of triploid male-sterile dandelion Taraxacum belorussicum (section Palustria) from Poland. While this taxon is considered to be a male-sterile species, we found that the investigated individuals produced pollen. Irregular tetrads, triads and diads with microspores of unequal size were observed in the pollen loculi as a result of disturbed meiotic division, while anthers’ tapetum did not show structural disorders. Possible reasons for the plasticity in the expression of male sterility, as well as the role of pollen in apomicts, are discussed. Flowers of the examined individuals contained well-developed nectaries. The course of embryological processes in the ovules indicated an apomictic mode of reproduction in T. belorussicum. We observed meiotic diplospory of the Taraxacum type, in which first meiotic division starts but results in nuclear restitution, while undisturbed second meiotic division gives rise to a dyad of unreduced megaspores (diplodyad). After three mitotic divisions of the chalazal megaspore, a seven-celled unreduced female gametophyte developed. The features of ovule anatomy and characteristics of a mature female gametophyte corresponded to these described in sexually reproducing dandelions

Distribution of Taraxacum microspecies along soil property gradients in salt and brackish meadows on the Polish Baltic coast

The vegetation of protected salt meadows along the Baltic coast is fairly well known; however, dandelions have been so far treated as a collective species. The aim of our study was to examine the microspecies diversity of the genus Taraxacum in Polish salt and brackish coastal meadows and to analyse soil property preferences of the dandelion microspecies identified. In addition, we analysed the relations between soil properties and vegetation patterns in dandelion-supporting coastal meadows (by canonical correspondence analysis). The salt and brackish meadows along the Polish Baltic coast we visited were found to support a total of 27 dandelion microspecies representing 5 sections. Analysis of vegetation patterns showed all the soil parameters (C:N ratio, organic matter content, pH, concentration of Mg, P, K, electrolytic conductivity of the saturated soil extract ECe) to explain 32.07% of the total variance in the species data. The maximum abundance of most dandelion microspecies was associated with the highest soil fertility, moderate pH values and organic matter content, and with the lowest magnesium content and soil salinity. The exceptions were T. latissimum, T. stenoglossum, T. pulchrifolium and T. lucidum the occurrence of which was related to the lowest soil fertility and the highest salinity. In addition, several microspecies (T. leptodon, T. gentile, T. haematicum, T. fusciflorum and T. balticum) were observed at moderate C:N ratios and ECe. Four other microspecies (T. infestum, T. cordatum, T. hamatum, T. sertatum) occurred at the lowest pH and organic matter content. The information obtained increases the still insufficient body of knowledge on ecological spectra of individual dandelion microspecies, hence their potential indicator properties

Chromosome numbers in 10 Taraxacum species from Poland

Somatic chromosome numbers are given for the following Taraxacum species: T. pieninicum, 2n=16; T. dentatum, 2n=24; T. fascinans, 2n=24; T. mendax, 2n=40; T. subalpinum, 2n=24; T. telmatophilum, 2n=24; T. cyanolepis, 2n=24; T. fulgidum, 2n=24; T. gentile, 2n=24; and T. undulatum, 2n=24. Chromosome numbers from Poland are published for the first time for T. dentatum, T. fascinans, T. mendax, T. subalpinum, T. telmatophilum, T. cyanolepis, T. fulgidum, T. gentile and T. undulatum