Morphological,chorological and ecological plasticity of Cistus incanus in the southern Balkans

Abstract

Two subspecies of Cistus incanus L. occurring in the southern Balkans were studied: C. incanus L. ssp. incanus and C. incanus ssp. creticus (L.) Heywood. After studying the morphological differences, the communities dominated by these two subspecies were sampled according to the central European method. The localities of the relevés show the distribution pattern of the two subspecies. The typical subspecies can be found in the area of distribution of thermophilous deciduous forests of Carpinion orientalis, whereas the subspecies creticus grows in the area of the evergreen broad‐leaved forests of Quercetea ilicis. The communities were classified as Diantho–Cistetum incani Micevski et Matevski ex ?arni, Matevski et ?ilc ass. nova hoc loco and Calicotomo villosae–Cistetum cretici Oberdorfer 1954. Analyses of traits (life span, life form, proportion of certain families, bioindicator values and chorotypes) reveal that the harshest site conditions prevail within Diantho–Cistetum incani, which appears as an initial stage of the vegetation succession. Calicotome–Cistetum cretici is a subsequent stage of succession, since the extreme degradation of vegetation on these sites results in ephemeral communities dominated by Poa bulbosa assigned to Romulion.     

Realization of the project for Acipenser oxyrhynchus oxyrhynchus restoration in the basin of the Neman River

The results of the works on the international project for the Baltic sturgeon restoration in the basin of the Neman River are considered. The mutual goal of the project is the restoration of the Baltic sturgeon population in its whole former area in the Baltic Sea. Successful works on the restoration of the Baltic sturgeon population are conducted in the Oder and the Vistula basins. The stockings of the Neman River with the sturgeon fry were started from 2012 year. It is contemplated that the sturgeon stockings of the main rivers of the Baltic Sea will enable to restore local sturgeon populations in these river basins. Till the beginning of the XXI century it was supposed that the Atlantic sturgeon Acipenser sturio had inhabited the Baltic Sea, but numerous genetic analysis of the samples of the sturgeon bones from the archeological finds in the museums showed that the Baltic Sea had been inhabited with Acipenser oxyrhynchus and its population still inhabits several rivers in Canada. This discovery permitted to start the creation of the Baltic sturgeon broodstock. Sturgeon fry from the eggs imported from Canada were used for stocking at the first stage of the project. Later it is contemplated to use the fry from the broodstocks in Germany and Poland. Sturgeon fry hatched from Canadian eggs in Poland and reared in Lithuania was used for the Neman River stocking. The fry were tagged and released in the Neris and the Sventoji Rivers in the Neman River basin. The sturgeon migrated into the Curonian lagoon where the monitoring of the catches was fulfilled. The results of sturgeon catches monitoring are discussed.     

Anthocyanin contribution to chlorophyll meter readings and its correction

Leaf chlorophyll content is an important physiological parameter which can serve as an indicator of nutritional status, plant stress or senescence. Signals proportional to the chlorophyll content can be measured non-destructively with instruments detecting leaf transmittance (e.g., SPAD-502) or reflectance (e.g., showing normalized differential vegetation index, NDVI) in red and near infrared spectral regions. The measurements are based on the assumption that only chlorophylls absorb in the examined red regions. However, there is a question whether accumulation of other pigments (e.g., anthocyanins) could in some cases affect the chlorophyll meter readings. To answer this question, we cultivated tomato plants (Solanum lycopersicum L.) for a long time under low light conditions and then exposed them for several weeks (4 h a day) to high sunlight containing the UV-A spectral region. The senescent leaves of these plants evolved a high relative content of anthocyanins and visually revealed a distinct blue color. The SPAD and NDVI data were collected and the spectra of diffusive transmittance and reflectance of the leaves were measured using an integration sphere. The content of anthocyanins and chlorophylls was measured analytically. Our results show that SPAD and NDVI measurement can be significantly affected by the accumulated anthocyanins in the leaves with relatively high anthocyanin content. To describe theoretically this effect of anthocyanins, concepts of a specific absorbance and a leaf spectral polarity were developed. Corrective procedures of the chlorophyll meter readings for the anthocyanin contribution are suggested both for the transmittance and reflectance mode.     

Elucidating the evolution and diversity of Uroglena-like colonial flagellates (Chrysophyceae): polyphyletic origin of the morphotype

ABSTRACT

The Uroglena-like morphotype represents a prototype of a colonial naked chrysophyte, comprising plastid-bearing cells that are arranged as the surface monolayer of the spherical colony. So far, insufficient molecular characterization appears to be the most significant brake on the modern taxonomic revision of this ecologically and morphologically coherent group of organisms. The general aim of this work was to conduct a modern taxonomic revision of Uroglena-like flagellates by using combined molecular, morphological and ultrastructural methodology, complemented by exploring type localities of Uroglena volvox and Uroglenopsis americana in Europe and North America, respectively. On the basis of phylogenetic analysis of concatenated nuclear SSU rDNA and plastid rbcL sequences we show that Uroglena-like colonial flagellates form three genetically and morphologically distinct lineages within the Ochromonadales (Chrysophyceae), distinguished here as Uroglena, Uroglenopsis and Urostipulosphaera gen. nov. The taxonomic status of the other chrysophyte genera with spherical colonies is discussed in light of our findings.     

Evaluation of adamantane hydroxamates as botulinum neurotoxin inhibitors: Synthesis,crystallography, modeling,kinetic and cellular based studies

Botulinum neurotoxins (BoNTs) are the most lethal biotoxins known to mankind and are responsible for the neuroparalytic disease botulism. Current treatments for botulinum poisoning are all protein based and thus have a limited window of treatment opportunity. Inhibition of the BoNT light chain protease (LC) has emerged as a therapeutic strategy for the treatment of botulism as it may provide an effective post exposure remedy. Using a combination of crystallographic and modeling studies a series of hydroxamates derived from 1-adamantylacetohydroxamic acid (3a) were prepared. From this group of compounds, an improved potency of about 17-fold was observed for two derivatives. Detailed mechanistic studies on these structures revealed a competitive inhibition model, with a K_i = 27 nM, which makes these compounds some of the most potent small molecule, non-peptidic BoNT/A LC inhibitors reported to date.     

The effects of lactic acid bacteria inoculants and formic acid on the formation of biogenic amines in grass silages

Silages were prepared in six laboratory experiments from four direct-cut grassland swards and pure swards of perennial ryegrass and false oat with dry matter contents ranging between 180 and 325?g/kg. Grass was fermented at 22°C and silages were stored at the same temperature for 4 months. Untreated silages (negative control) and silages preserved with 3?g/kg of formic acid (positive control) were compared with silages inoculated with commercial strains of Lactobacillus plantarum, Lactobacillus buchneri and a mixed preparation Microsil. The inoculants were applied at a dose of 5.10⁶ CFU/g of grass. Seven biogenic amines were extracted from silages with perchloric acid and determined as N-benzamides by micellar electrokinetic capillary chromatography. Common chemical quality parameters of silages were also determined. Tyramine, cadaverine and putrescine were the amines occurring at the highest concentration. As compared to untreated silages, formic acid was most effective to suppress formation of the main amines. Also the inoculants often decreased amine contents significantly (P?相似文献