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Viola uliginosa is an endangered species throughout its range in Central Europe. Based on an unusual combination of morphological characters, including a reported lack of cleistogamous ( CL) flowers, it was previously placed in the monotypic subsection Repentes, section Viola. Available individual phylogenetic analyses identify V. uliginosa as a lineage deeply embedded in section Viola, but hitherto its exact position was unknown. Here we confirm the occurrence of cleistogamy in V. uliginosa. Unlike other species of section Viola, V. uliginosa produced both chasmogamous and CL flowers at the same time, not at different times of the year (seasonal cleistogamy). The two flower types differed conspicuously in morphology and microstructure, especially in size and shape of the pistil and stamens as confirmed by scanning electron microscopy. Secondly, we resolved the phylogenetic position of V. uliginosa as a lineage deeply embedded in subsection Rostratae by means of a multigene multispecies coalescent analysis using * BEAST. In this analysis, V. mirabilis and V. uliginosa were successive sisters to the rest of subsection Rostratae and, because allopolyploids exist between V. mirabilis and the last one, subsection Rostratae needs to comprise all these taxa to be monophyletic. The evolution of key morphological traits is briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract. The plants growing in the natural environment are exposed to the influence of adverse factors which can cause metabolic disturbances, inhibition of growth, damage tissues and organs. The particular threats to plants are heavy metals, especially cadmium which inhibits plant growth and development. The aim of this study was to determine the influence of cadmium nitrate at concentrations of 0.01, 0.05 and 0.1 mM on seed germination, plants length, fresh and dry weight and the water content in Lupinus luteus L. and L. angustifolius L. The cadmium which is present in soil causes inhibition of seed germination, changes in root and hypocotyl length, value of fresh to dry weight ratio and the water content in plants organs. [ABSTRACT FROM AUTHOR]

The article discusses the usefulness of morphological characters in determination of intra- and interspecific diversity of violets or violaceae. It analyzes the intra- and interpopulation differentiation in Viola tricolor L. To determine the differences influenced by environmental conditions, the morphological and anatomical features in metallicolous and non-metallicolous populations are examined.

The article discusses studies on the embryological characters of the angiosperms belonging to the family Violaceae. It notes that despite differences in morphology, microstructure and molecular structure within the genus, several Viola L. species exhibit uniformity in ovule characters, female gametophyte, embryo and development of endosperm. Abnormalities in female gametophytes of the examined species are attributed to pollution from heavy metals and from hybridization.