The antimicrobial activity of aqueous and ethanolic extracts of 11 Bryophyta species and 9 Marchantiophyta species collected in Latvia was tested against Staphylococcus aureus, Escherichia coli and Bacillus cereus. The extract of Lophocolea heterophylla inhibited the growth of B. cereus, but none of the tested extracts inhibited the growth of E. coli. 70% of bryophyte species demonstrated certain activity in relation to S. aureus. In general, 73% of ethanolic extracts and 39% of aqueous extracts exhibited antibacterial activity against S. aureus. The highest degree of antibacterial activity against S. aureus was shown by the ethanolic extract of Dicranum scoparium and aqueous extracts of Atrichum undulatum and Rhytidiadelphus squarrosus. The bactericidal action was not ascertained. For the first time antimicrobial activity has been proved for three moss species-Eurhynchium angustirete, Rhytidiadelphus squarrosus and Rhodobryum roseum, and for two liverwort species Frullania dilatata and Lophocolea heterophylla. Qualitative and quantitative differences of plant extracts were evaluated by FT-IR spectra.

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The aim of the study was to analyse if the measurement of fast fluorescence induction kinetics in bryophyte samples in field conditions could be used for characterizing the photochemistry of photosynthesis in bryophytes. Bryophyte samples were collected in five different habitats of the boreo-nemoral zone growing on various substrates. Twenty-four species were epigeic, six epilithic, ten epiphytic, three epixylic, and six semi-aquatic or aquatic. Extremely high variation was found for fluorescence parameters between bryophyte samples. Performance Index showed the highest variability, reaching 160% in the case of epiphytic bryophytes. There were statistically significant differences for mean values of FJF,", RC/ABS, and FJFQ between epigeic and epiphytic bryophyte samples as well as between epiphytic and semi-aquatic & aquatic samples. For Perfonnance Index, a significant difference was observed only between epiphytic and epigeic bryophytes. It was concluded that bryophytes display a low intensity of the photochemistry of photosynthesis even in relatively wet habitats. In general, measurement of fast fluorescence induction kinetics in field conditions could be a rapid and efficient tool to obtain quantitative data useful for ecophysiological studies.

The aim of the present study was to determine a relationship between physiological traits and functional types of bryophytes from five boreonemoral habitats with a particular emphasis on discriminative ability of these traits. Sampling of 25 species was performed four times during one season. Water content, chlorophyll a fluorescence and photosynthetic pigment concentration were measured in field and water-equilibrated samples. Principal component analysis indicated the existence of an inverse relationship between concentration of pigments and water content. Linear discriminant analysis showed that relatively high mean predicted posterior probabilities of correct classification of functional types by physiological traits were found for water conducting system, followed by substrate and habitat, but it was highly variable and type-specific for life form and relatively less variable for life strategy. Field water content had the highest average discriminative importance among physiological traits, followed by chlorophyll fluorescence indices field Fv/Fm, equilibrated PI, equilibrated RC/ABS, and field RC/ABS. Photosynthetic pigment concentrations had relatively less average importance for classification of functional types.