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The content of various heavy metals (arsenic, cadmium, chromium, copper, iron, lead, mercury, nickel, manganese and zinc) in the moss species Rhodobryum ontariense (Kindb.) Kindb. and its tea are presented in this study. Pursuant to the use of this tea in traditional Chinese medicine for hypertension, the aim of this study was to examine its safety in regard to the metals. All heavy metals were determined by adequate EPA methods. The concentrations of all metals for daily intake in its tea were below the safety levels for human consumption. These results indicate the importance of manganese in R. ontariense tea traditionally used for hypertension and other heart disorders. [ABSTRACT FROM AUTHOR]

Although the second biggest terrestrial group of plants, bryophytes remain poorly known chemically compared to the angiosperms. In this article, the sugars of the moss Rhodobryum ontariense, an unstudied representative of the medicinally known genus, are reported. The chemical analysis revealed the usual plant sugar sucrose, and a new sugar, fructooligosaccharide 1-kestose, which is reported first not only for the genus Rhodobryum, but also for mosses. The trisaccharides have been scantily reported in bryophytes hitherto. This gives more significance to this study for further investigation of its role in the moss species. The health-promoting effect of 1-kestose is also briefly discussed. [ABSTRACT FROM PUBLISHER]

The use of in vitro techniques for conservation has been rising steadily since their inclusion in The Convention on Biological Diversity and The Global Strategy for Plant Conservation. Unfortunately, bryophytes are often overlooked in conservation initiatives, but they are important in a number of large-scale ecosystem processes, i.e. nutrient, water and carbon cycling. There is a long history of the use of tissue culture in cultivating bryophytes, and many species respond well to in vitro techniques. For 6 yr (2000-2006), The Royal Botanic Gardens, Kew and the UK statutory conservation agencies supported a project for the ex situ conservation of bryophytes. Living and cryopreserved collections of UK threatened species were successfully established and the cryopreserved collection continues to be maintained. Other in vitro conservation collections are maintained over Europe, at botanic gardens, museums and by individual university researchers, but there is no coherent European collection of bryophytes for conservation, or standardisation of techniques. A major issue for many in vitro collections is the maintenance of within species genetic diversity. Such diversity is considered to be important, as it is the basis by which populations of species can adapt to new conditions and evolve. We are proposing to establish a European network for in vitro conservation of bryophytes. We envisage that this will include living collections, cryopreserved collections and spore collections. Conservation of genetic diversity would be a priority and the collections would provide a valuable resource for conservation initiatives and support research into rare and threatened species. [ABSTRACT FROM AUTHOR]

Seed plant genera often exhibit intercontinental disjunctions where different species are found on different continents. Many morphologically circumscribed bryophyte species exhibit similar disjunctions. We used nucleotide sequences from the plastid and nuclear genomes to test hypotheses of phylogeography within representatives of the genus Metzgeria: Metzgeria furcata, Metzgeria conjugata, and Metzgeria myriopoda. The first two species have sexual and asexual populations, exhibit disjunctions between North America and Europe, and have been split into separate species, numerous subspecies or varieties. The third species occurs in eastern North America but is not reported from Europe. Phylogenetic analyses resolved three distinct lineages within the morphologically defined species, M. furcata: one in North America, and two in Europe. Similarly, three morphologically cryptic clades of M. conjugata were resolved by the molecular data: northern North America, Europe, and south-eastern North America. For both species, molecular divergence among taxa occurred in the absence of morphological change. In the case of M. myriopoda, all plants from eastern North America were both morphologically uniform and genetically homogeneous (although not identical). The present study provides significant insight into a plant group with complex taxonomy, and indicates that these liverwort taxa with wide distributions, extreme sex ratios, and continental disjunctions harbor cryptic lineages. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 745–756. [ABSTRACT FROM AUTHOR]

Crossidium laxefilamentosum Frey & Kürschner is shown to be a distinct taxon that is easily distinguished from the related C. crassinerve. Discovery of two plants of C. laxefilamentosum with sporophytes has permitted the description of the capsule and spore characters for the first time. This species is recorded as new to Europe and to North Africa. The known range of this desert species is now expanded from South-West Asia to North Africa, to the steep loess cliffs along the River Danube, and to the dry S. E. coast of the Iberian Peninsula. Among these regions five localities are reported from northern Serbia, three from central Hungary, S. of the 47° line of latitude, one from Romania, 20 from Spain and six localities have been found in Tunisia. The distribution of C. laxefilamentosum suggests that it had a circum-Tethyan origin. [ABSTRACT FROM AUTHOR]

Two moss species, Bryum argenteum Hedw. and Atrichum undulatum (Hedw.) P. Beauv., were treated with different phytohormones in order to investigate their morphogenesis. In vitro cultures of these two moss species were established from sterilized spores. The apical shoots of untreated gametophytes grown in vitro were used to investigate the influence of different growth substances on secondary protonema and on growth and multiplication of the gametophyte. The two moss species react differently to the growth regulators applied. [ABSTRACT FROM AUTHOR]

In vitro cultures of five moss species were established on hormone-flee MS medium, or on MS medium supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid and kinetin. In vitro culture of Eurhynchium praelongum (Hedw.) B., S. & G., has been initiated from the apical shoots of the gametophytes, and the cultures of Aloina aloides (K.F.Schultz) Kindb. Brachythecium velutinum (Hedw.) B., S. & G., Ceratodon purpureus (Hedw.) Brid. and Grimmia pulvinata (Hedw.) Sm. were initiated from the spores of immature sporophytes. In secondary protonema culture of Eurhynchium praelongum, spontaneous regeneration occurred successfully. Protonema cultures of Aloina aloides, Brachythecium velutinum and Ceratodon purpureus reversed to caulonema culture where bud formation occurred. Grimmia pulvinata cultures remained at the protonema stage. [ABSTRACT FROM AUTHOR]

Bryophytes are widely used to monitor air quality. Due to the lack of a cuticle, their cells can be compared to the roots of crop plants. This study aimed to test a hypothetical relation between metal tolerance and cell shape in biomonitoring mosses (Hypnum cupressiforme, Pleurozium schreberi, Pseudoscleropodium purum) and metal sensitive species (Physcomitrium patens, Plagiomnium affine). The tolerance experiments were conducted on leafy gametophytes exposed to solutions of ZnSO4, ZnCl2, and FeSO4 in graded concentrations of 1 M to 10−8 M. Plasmolysis in D-mannitol (0.8 M) was used as a viability measure. The selected species differed significantly in lamina cell shape, cell wall thickness, and metal tolerance. In those tested mosses, the lamina cell shape correlated significantly with the heavy metal tolerance, and we found differences for ZnSO4 and ZnCl2. Biomonitoring species with long and thin cells proved more tolerant than species with isodiametric cells. For the latter, "death zones" at intermediate metal concentrations were found upon exposure to ZnSO4. Species with a greater tolerance towards FeSO4 and ZnSO4 had thicker cell walls than less tolerant species. Hence, cell shape as a protoplast-to-wall ratio, in combination with cell wall thickness, could be a good marker for metal tolerance. [ABSTRACT FROM AUTHOR]

A limited number of mosses has ever been studied regarding antioxidant activity among which only a few are European species. As a part of our ongoing screening of new promising bryophyte resources of natural antioxidants, a relevant biological activity investigation was conducted on the mossBryum moravicumPodp. (Bryaceae) collected in Germany. The antioxidant activity of an aqueous extract of the species was evaluatedin vitroby analysing its ABTS [2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] cation scavenging activity and total phenolic content. The study led to the detection of a moderate antioxidant activity: 1 mg of the extract was equivalent to 84.56 ± 7.93 µg of ascorbic acid. The total phenolic content in 1 mg of the extract was equivalent to 356.44 ± 9.56 µg of ferulic acid used as a standard. These results have indicated for the first time potential importance ofB. moravicumin searching for novel antioxidant agents. [ABSTRACT FROM PUBLISHER]