The leaf epidermis of 36 taxa (species, subspecies, varieties and cultivars) of the genus Ficus (subgenera Ficus, Synoecia, Sycomorus, Pharmacosycea and Urostigma) was observed under LM and SEM. Characteristics of the epidermis are of particular taxonomic as well as phylogenetic interest because they differ conspicuously between species. The differences are especially prominent in the size and shape of epidermal cells, the shape of cell walls, peristomatal cuticular rim, the distribution and position of stomata, lithocysts, hydathodes, trichomes, and the types of wax, cuticle and trichomes. Results of this study provided data on new qualitative and quantitative traits of the leaf epidermis in the selected taxa, and confirmed the classification suggested by Berg (1989)

Veronico-Mimuletum guttati, a poorly known association of species-rich helophyte beds communities was characterizedbased on 21 phytosociological relevés. Its new 14 localities in Pomerania and floristic differentiation in Central Europe are presented. New subassociations of the Veronico-Mimuletum guttati cardaminetosum amarae have been distinguished on the basis of differing floristic composition. It is further differentiated into two syntaxa: spring variant noted in spring areas and typical variant noted in banks of rivers, ditches and water-logged meadows.

The aim of this study was to compare the antibacterial effects of several essential oils derived from plants belonging to family Pinaceae and subfamily Abietoideae (cedar oil, fir oils derived from Silver fir Abies alba Mill. and Siberian fir Abies sibirica L., respectively) against some Gram-positive and Gramnegative bacteria. The Kirby-Bauer disk diffusion test for measuring zone diameters of bacterial growth inhibition was used. The fir oil derived from Silver fir Abies alba showed considerably more profound activity than the cedar oil and fir oil derived from Siberian fir Abies sibirica. Maximum antibacterial activity was shown by essential oil of silver fir oil against Escherichia coli, methicillin-sensitive Staphylococcus aureus (MSSA), and Pseudomonas aeruginosa. Silver fir essential oil was found to be active against K. pneumoniae while Siberian fir essential oil showed the mild activity of clear inhibition zone against P. aeruginosa and methicillin-sensitive Staphylococcus aureus. Silver fir essential oil has the highest antibacterial potential from all tested essential oils and could be a promising candidate concerning possible applicability in the prevention of bacterial growth. Moreover, essential oils may play an important role in the discovery of new drugs for the treatment of a wide range of pathogenic microorganisms in the near future. This study provides insight into the in vitro antibacterial activity of a wide variety of essential oils derived from many different plant genera against pathogenic bacteria. The data contributes to the ongoing scientific investigation regarding the application of essential oils as natural antibacterial agents.

No abstract

Pollen grains of 9 species of the genus Plantago (Plantaginaceae), including 8 taxa native to Poland, were observed under a light microscope and a scanning electron microscope. Descriptions of grain sculpture are illustrated only SEM micrographs. The studied pollen grains were medium-sized or small, spherical or prolate spheroidal. Their sculpture was always verrucate with granulation. In the studied taxa, internal apertures had the form of pores. Their number ranged from (4)5-9(14). The pores were scattered on the surface of pollen grains. Identification features of individual taxa include: presence or absence of an annulus around each pore, annulus structure, ornamentation of the pollen grain and operculum, type of aperture membrane, number of internal pores, and pore diameter. We suggest that two new pollen grain types, characteristic of P. intermedia and P. arenaria, should be distinguished, and that P. alpina should be assigned to the P. coronopus type