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Polyphenolic Characterization, Antioxidant, Antihyaluronidase and Antimicrobial Activity of Young Leaves and Stem Extracts from Rubus caesius L.
Fruits are the main food part of the European dewberry (Rubus caesius L.), known as a source of polyphenols and antioxidants, while very little attention is paid to leaves and stems, especially young first-year stems. The purpose of this work was to analyze for the first time water and ethanol extracts obtained from young, freshly developed, leaves and stems of the European dewberry to determine their antioxidant and biological activity, whereas most of the papers describe biological properties of leaves collected during summer or autumn. As the phytochemical profile changes during the growing season, the quantitative and qualitative content of flavonoid glycosides and flavonoid aglycones was analyzed using reversed phase liquid chromatography/electrospray ionization triple quadrupole mass spectrometry (LC-ESI-MS/MS) with multiple reaction monitoring (MRM). The ability to inhibit hyaluronidase as well as antioxidant activity (2,2 diphenyl-1-picrylhydrazyl: DPPH and ferric antioxidant power: FRAP) were estimated. Extracts were also analyzed against Gram-positive and Gram-negative bacteria. The results of the qualitative phytochemical analysis indicated the presence of flavonoid aglycones and flavonoid glycosides, with the highest amount of tiliroside, hyperoside, isoquercetin, astragalin, rutin and catechin in ethanol extracts. DPPH and FRAP tests proved the high antioxidant activity of the extracts from leaves or stems and the antihyaluronidase assay revealed for the first time that water and ethanol extracts obtained from the stems exhibited the ability to inhibit hyaluronidase activity resulting in an IC50 of 55.24 ± 3.21 and 68.7 ± 1.61 ÎŒg/mL, respectively. The antimicrobial activity has never been analyzed for European dewberry and was the highest for Clostridium bifermentans and Clostridium sporogenesâanaerobic sporulation rods as well as Enterococcus faecalis for both water and ethanol extracts.
Salix Ăbrowiczii (Salicaceae) â a new nothospecies from northeastern Greece
A hybrid between Salix triandra and S. xanthicola, occurring in the Rhodope Mountains in northeastern Greece, is described as a new nothospecies. It differs from S. triandra by having distinctly hairy young stems and more deeply serrate-dentate leaf margins, and from S. xanthicola by a smooth, unstructured (without conicoids) wax layer on the lower side of the leaves and the presence of subsessile glands on the petioles.
Thuja Ăsoeegaardii (Cupressaceae) â a new name for an old hybrid
Thuja Ăsoeegaardii, a hybrid of Th. plicata Donn ex D.Don and Th. standishii (Gordon) CarriĂšre, is described as a new nothospecies from the KĂłrnik Arboretum, Poland, based on plants obtained in 1988 from the Botanical Garden in Gothenburg, Sweden. The hybrid was found for the first time at the HĂžrsholm Arboretum, Denmark, in 1938, among seedlings grown from seeds collected from Thuja standishii. Plants grown from rooted scions of this hybrid were planted in several places within the HĂžrsholm Arboretum. Soon, the hybrid plants were gifted to the Botanical Gardens in Copenhagen and Gothenburg as well to the Poulsenâs Plant Nursery in KvistgĂ„rd. In 1967 seedlings were sent from KvistgĂ„rd to the National ArÂboretum in Washington, where one of them developed into a particularly showy, lush and vigorous plant characterized by a dense, narrow, conical crown. The offspring obtained from rooted scions turned out to be very drought and wind-resistant, especially suitable for the formation of tall hedges and windbreak screens. This plant, now very widespread in cultivation, especially in the United States, goes by the name of Thuja âGreen Giantâ. In terms of morphology, many features of Th. Ăsoeegaardii are intermediate as compared to the parent species. From the Th. plicata, it differs by the following characteristics: leaves not or only weakly shining above, lateral leaves with inwardly curved (not straight) apices, the apical part of lower central leaves thickened and slightly bent from the stem (not appressed), glands on central leaves only weakly visÂible, central leaves of primary shoots acuminate (not long acuminate) and seed wings sparsely papillose in the upper part (only rarely smooth). From Th. standishii, it can be distinguished by the less glaucous upper leaf surface, the less protruding apical part of lower central leaves, at least faintly visible glands on central leaves, acuminate (not acute) central leaves of primary shoots and less distinctly papillose upper part of seed wings.
The evolutionary heritage and ecological uniqueness of Scots pine in the Caucasus ecoregion is at risk of climate changes
AbstractScots pine is one of the most widely occurring pines, but future projections suggest a large reduction in its range, mostly at the southern European limits. A significant part of its range is located in the Caucasus, a global hot-spot of diversity. Pine forests are an important reservoir of biodiversity and endemism in this region. We explored demographic and biogeographical processes that shaped the genetic diversity of Scots pine in the Caucasus ecoregion and its probable future distribution under different climate scenarios. We found that the high genetic variability of the Caucasian populations mirrors a complex glacial and postglacial history that had a unique evolutionary trajectory compared to the main range in Europe. Scots pine currently grows under a broad spectrum of climatic conditions in the Caucasus, which implies high adaptive potential in the past. However, the current genetic resources of Scots pine are under high pressure from climate change. From our predictions, over 90% of the current distribution of Scots pine may be lost in this century. By threatening the stability of the forest ecosystems, this would dramatically affect the biodiversity of the Caucasus hot-spot.
Morphological differences in populations of Jacobaea erucifolia: Genetic differentiation, phenotypic plasticity or ecotypes?
Accurate taxonomic classification is essential for effective conservation strategies, especially for rare and endangered species. Traditionally based on morphology, such classifications may be challenged by recent advances in molecular tools that reveal hidden genetic structure or lack thereof. Jacobaea erucifolia is a declining species in Poland, primarily threatened by habitat loss, fragmentation, and competition with invasive species. Although two subspeciesâerucifolia and tenuifoliaâhave been identified in Poland based on leaf morphology and ecological preferences, the taxonomic status of these forms remains unclear. This study aimed to evaluate the genetic variation within ten Polish populations of J. erucifolia and assess whether the observed morphological differences correspond to genetic divergence. Based on morphology, four populations were classified as subsp. erucifolia and six as subsp. tenuifolia. Reference populations of confirmed subspecies tenuifolia were included from Slovakia, Hungary, and the Netherlands. Genetic analyses were conducted using amplified fragment length polymorphisms (AFLPs), chloroplast DNA restriction fragments (RFLP), cpDNA, and nuclear internal transcribed spacer (ITS) ribosomal DNA sequences. The results revealed a high level of admixture and no significant genetic differentiation among Polish populations, regardless of their initial morphological classification. All Polish populations formed a single genetic group, distinct from foreign tenuifolia samples, although no diagnostic genetic markers were identified to separate these two groups (subspecies) of J. erucifolia definitively. Moreover, sequence data showed no differences among all analyzed individuals, further challenging the validity of subspecies differentiation. These findings suggest that the morphological variation observed within Polish populations likely reflects phenotypic plasticity rather than subspecies-level divergence. Consequently, subspecies tenuifolia does not appear to occur in Poland, and observed differences between Polish populations and those from neighboring countries may represent ecotypic variation. Our study underscores the necessity of integrating genetic and morphological data when resolving taxonomic ambiguities, especially in the context of conservation planning. Future research involving broader geographic sampling and deeper analysis of hybridization patterns will help clarify the evolutionary history and and population dynamics of J. erucifolia.
Revisiting the taxonomy of Populus lasiocarpa Ă P. wilsonii hybrids
Although hybrids between Populus lasiocarpa and P. wilsonii have been known for many years, they have not been given a valid nothospecies name. Resolving the classification issue of these bigleaf poplars is now even more necessary because they are known not only from cultivation, but recent evidence confirms their spontaneous occurrence in Hubei Province, China (Zhang, unpublished information). The two species were first artificially crossed in 1956 in Poland and again independently in 1974 in Sweden. Initially, this taxon was described as P. Ăwilsocarpa (Bartkowiak & BugaĆa, 1978). However, this name was invalid due to the lack of Latin diagnosis (which was required at that time) and lack of type designation. In 1996, Böcker and Koltzenburg proposed the name P. Ăkornicensis for this hybrid, but it too was invalid for similar reasons and lack of description. In our work, we revisited these poplars and validated the name proposed by Böcker and Koltzenburg by providing a description and type designation. Considering the overall appearance of these hybrid poplars (silhouette, branching pattern), they bear a closer resemblance to P. wilsonii. Other analyzed morphological features are mostly intermediate compared to the parent species, but overall, they lean slightly more towards P. lasiocarpa. We highlight the main diagnostic characteristics that distinguish these species.
Hybrid zones in the European Alps impact the phylogeography of alpine vicariant willow species (Salix L.).
IntroductionIn the European Alps, Pleistocene climate oscillations resulted in geographical range expansions and restrictions of species. Postglacial recolonizations often result in secondary contact hybridization of vicariant species, thereby creating hybrid zones with patterns of introgression. Here, we compare the genetic structure of two secondary contact hybrid zones between two vicariant willow species pairs occurring in the European Alpine System. Supplemented by morphological and ecological data, we try to understand the factors shaping the hybrid zones and their influence on geographical range filling patterns.MethodsRAD sequencing and morphometric data were used to characterize biogeographical history, genetic diversity and the hybrid zone of each species pair. Vegetation relevés and species distribution models provided ecological context and support.Key resultsResults suggest that recolonization of the Alps happened from peripheral glacial refugia, resulting in broad secondary contact zones in the Eastern Alps in both species pairs. Both hybrid zones show introgression, but differ in symmetry and intensity of gene flow, in the type of introgressed loci, and in the geographical range. Habitat preferences and species distribution models do not indicate ecological barriers to recolonization.ConclusionsHybrid zones do not only affect the genetic structure of species by gene flow and introgression, but also appear to impact the biogeographical patterns of species.
No wonder, it is a hybrid. Natural hybridization between Jacobaea vulgaris and J. erucifolia revealed by molecular marker systems and its potential ecological impact
AbstractProgressive changes in the environment are related to modifications of the habitat. Introducing exotic species, and interbreeding between species can lead to processes that in the case of rare species or small populations threatens their integrity. Given the declining trends of many populations due to increased hybridization, early recognition of hybrids becomes important in conservation management. Natural hybridization is prevalent in Jacobaea. There are many naturally occurring interspecific hybrids in this genus, including those between Jacobaea vulgaris and its relatives. Although Jacobaea erucifolia and J.âvulgaris often coâoccur and are considered closely related, apart from the few reports of German botanists on the existence of such hybrids, there is no information on research confirming hybridization between them. Morphologically intermediate individuals, found in the sympatric distributions of J.âvulgaris and J.âerucifolia, were hypothesized to be their hybrids. Two molecular marker systems (nuclear and chloroplast DNA markers) were employed to test this hypothesis and characterize putative hybrids. Nuclear and chloroplast DNA sequencing results and taxonâspecific amplified fragment length polymorphism (AFLP) fragment distribution analysis confirmed the hybrid nature of all 25 putative hybrids. The AFLP patterns of most hybrids demonstrated a closer relationship to J.âerucifolia, suggesting frequent backcrossing. Moreover, they showed that several individuals previously described as pure were probably also of hybrid origin, backcrosses to J.âerucifolia and J.âvulgaris. This study provides the first molecular confirmation that natural hybrids between J.âvulgaris and J.âerucifolia occur in Poland. Hybridization appeared to be bidirectional but asymmetrical with J.âvulgaris as the usual maternal parent.
Niche expansion of polyploid cytotypes shaped the phylogeographical history of the i Salix retusa complex in the European Alpine System
Abstract Background and Aims Alpine plants exhibit diverse postglacial recolonization patterns following the last glacial periods. Polyploidization may have impacted these dynamics by introducing ecological and physiological novelties that facilitate adaptation to changing environments. However, consistent trends in the recolonization, niche optima and dynamics of polyploids and their related diploids remain elusive. In this study, we investigate the biogeographical history of the Salix retusa polyploid complex in the European Alpine System. By comparing genetic patterns and their climatic and edaphic niche optima, we explore how polyploidization shaped speciesâ geographical distributions by influencing their ecological adaptation. Methods RAD sequencing was used to reconstruct the biogeographical history and genetic structure of two related willow species. High-resolution edaphic and climatic data were used to compare the niche optima, breadth and dynamics between the species. Key Results The distribution of the polyploid species overlaps with more peripheral refugial areas, which correlates with its broader geographical range in the European Alpine System. However, genetic analyses suggest more potential peripheral glacial refugia within the Alps for the diploid. Our findings indicate niche conservatism within the S. retusa complex, with the polyploid species having a broader niche but the diploid being adapted to a more extreme niche. Conclusions In our study species, polyploidy is associated with a higher genetic diversity and geographical structure, which might be due to a broader ecological niche and distribution. However, it did not appear to facilitate adaptation or confer a survival advantage during the last glaciation.