Search Results (8)

The progressive degradation of natural habitats, driven by anthropogenic pressures and climate change, constitutes one of the most serious threats to biodiversity. Peatland ecosystems, along with the valuable plant species associated with them, are particularly vulnerable to these processes. Salix lapponum, a glacial relict species, is undergoing a drastic decline in both its range and population size across Poland and Europe. This emphasizes the need for the implementation of conservation measures, including species translocation, as well as the development of effective methods for monitoring plant condition following introduction. The aim of this study was to evaluate the usefulness of selected physiological indicators for the rapid and reliable assessment of plant condition in active conservation efforts. The experimental material consisted of S. lapponum plantlets derived from tissue culture, which were introduced into five experimental sites in eastern Poland, differing in habitat conditions. Over two growing seasons, chlorophyll fluorescence parameters (F₀, F_m, F_v/F_m), the content of photosynthetic pigments and anthocyanins, relative water content, guaiacol peroxidase activity, and the presence of reactive oxygen species were analyzed. The results revealed clear seasonal variability in most of the studied physiological parameters, as well as their differentiation across habitat conditions. The highest sensitivity to environmental changes was observed for indicators related to photosynthetic performance (F_v/F_m), tissue hydration status (RWC), and enzymatic activity. Declines in photosystem II efficiency at the beginning of the growing season, reflected in F_v/F_m values decreasing to 0.47–0.49 indicate transient stress conditions in plants. Simultaneously, variation in relative water content (52–90%) and peroxidase activity reflects differences in water availability and the intensity of environmental stress across habitats. The findings confirm that selected physiological indicators can serve as effective tools for the early monitoring of plant condition and for assessing the success of S. lapponum translocation. Full article

Species translocation is an increasingly used method in active plant conservation, but its high costs and risk of failure highlight the need for prior research to support its effectiveness. Salix lapponum plantlets obtained through micropropagation were subjected to two biological experiments under laboratory conditions. The plants were watered with aqueous solutions of NaCl (Experiment 1) and N-NO₃ (Experiment 2) for a period of four weeks. The experiments were designed to simulate processes occurring in the natural habitats of the species- increased substrate salinity and eutrophication. To determine the plant response to the presence of NaCl and N-NO₃ in the soil substrate, various morpho-physiological traits were examined, including selected growth parameters, relative water content (RWC), photosynthetic pigment content, selected chlorophyll fluorescence parameters, reactive oxygen species (ROS) accumulation, antioxidant enzyme activity, and anthocyanin content. The results showed that both tested factors acted as abiotic stressors. Exposure to NaCl solutions of various concentrations led to a significant deterioration in morpho-physiological parameters, whereas low concentrations of nitrate nitrogen stimulated the growth of S. lapponum. In response to stress, the plants activated defense mechanisms such as increased anthocyanin synthesis, elevated antioxidant enzyme activity, and maintenance of a high relative water content. Full article

The abiotic stresses to which plants are exposed, especially in times of climate change, can result in the disruption of natural plant physiological processes. Sudden atmospheric phenomena may increase the risk of failure in protecting rare and extinction-threatened plant species by translocation. This study aimed to determine the effect of extreme ambient temperatures on the condition and physiological response of Salix lapponum plantlets used for their reintroduction into the natural habitat. Salix lapponum plants obtained by micropropagation methods at different stages of growth under laboratory conditions were subjected to a biological experiment. Plants were exposed for 12 h to temperature extremes (0 °C and 30 °C), after which the values of selected markers of the biochemical response were determined, such as photosynthetic pigments and anthocyanin content, guaiacol peroxidase and catalase activity, the presence of ROS and the RWC value. The study showed that plants at early growth stages were sensitive to low-temperature stress. In contrast, older ones showed a stronger response to high temperature, marked by an increased anthocyanin content and guaiacol peroxidase activity. It was also found that a short exposure to temperature extremes did not change the photosynthetic pigment content or catalase activity. The results of the study may be an important indication for the optimization of plant acclimatization methods in the process of their active protection by species translocation. Full article

The climatic changes that took place in Europe during the Quaternary period influenced plant habitats as well as their species and vegetation composition. In this article, biogeographical studies on Hercynian mountain plants that include data for the Alps, Carpathians, and European lowlands are reviewed in order to discuss the phylogeographical structure and divergence of the Hercynian populations from those in other European mountain ranges, Scandinavia, and lowlands. The analyzed studies show specific phylogeographical relations between the Hercynian mountains, Alps, Scandinavia, Carpathians, and European lowlands. The results also indicate that the genetic patterns of plant populations in the Hercynian Mountains may differ significantly in terms of origin. The main migration routes of species to the Hercynian ranges began in the Alps or Carpathians. Some species, such as Rubus chamaemorus L., Salix lapponum L., and Salix herbacea L., are glacial relics that may have arrived and settled in the Hercynian Mountains during the Ice Age and that survived in isolated habitats. The Hercynian Mountains are composed of various smaller mountain ranges and are a crossroads of migration routes from different parts of Europe; thus, intensive hybridization has occurred between the plant populations therein, which is indicated by the presence of several divergent genetic lines. Full article

Restoring endangered plant species to their historical sites is not always possible due to constantly changing habitat conditions. The aim of this study was to test the effects of reintroduction of two relict willow species in eastern Poland. The experiment consisted of planting 48 individuals of Salix lapponum and S. myrtilloides, obtained by micropropagation, at each of the two selected sites and observing their survival after one year. At the same time, selected physicochemical and biocenotic factors of the environment were monitored. About 70% of S. lapponum individuals and 50% of S. myrtilloides plants survived the one-year period. This result can be considered satisfactory and confirms the effectiveness of this means of active protection. The results of measurements of selected abiotic factors of the environment and the observations and ecological analysis of the flora indicated that the habitat conditions of both historical sites have changed, resulting in accelerated succession of vegetation. However, complete habitat degradation did not occur, although the development of a multi-story structure of one of the phytocenoses intensified competition for light and other environmental resources, which narrowed the potential ecological niche of the reintroduced species. Full article

The local populations of relict plant taxa living near the limits of their geographical range are particularly vulnerable to extinction. For example, Salix lapponum is one of the rarest and most endangered glacial relicts in Western and Central Europe. In Poland, the number of its sites has dramatically decreased over the past few decades, prompting us to take conservation measures focused on saving endangered populations. During a field experiment aimed at the reconstruction of the downy willow population in the Knyszyn Forest (NE Poland), 730 individuals of the species were planted in four different natural sites. The seedlings were obtained by micropropagation from parts of vegetative individuals taken from the most abundant population of this species in eastern Poland (Lake Bikcze). The success of the reintroduction, measured by the number of individuals that survived 2–3 years in the wild and took up growth, was about 67%, however, with low flowering efficiency (7.5%). Additionally, monitoring showed significant differences in plant survival and growth rates under different habitat conditions prevailing at the site and with different cover from competing species, especially tall grasses. However, the restoration projects for relict shrub species should include periodic removal of competing plants and protection of plants from trampling and browsing by herbivorous mammals to increase reintroduction success. Full article

Anthropogenic habitat transformations involving changes in hydrologic conditions in the peatlands of eastern Poland contribute to the disappearance of sites of numerous relict plant species. The study aimed to verify whether sites chosen for the reintroduction of the endangered species Salix lapponum had been well selected by analyzing selected habitat parameters and determining whether changes in their values may in the long term have a significant impact on the functioning of new populations of the species. The results obtained at sites where the S. lapponum population was replenished with new individuals were analyzed in relation to data from one of the natural sites of the species. Hydrochemical characterization of the groundwater at the study sites confirmed that there was no significant influx of nutrients into the habitat or other hydrological disturbances due to human activity. The values obtained for the factors tested were within the limits of the specific preferences of the species. Changes in the values of some physical-chemical parameters of the water were due to the ecosystem’s internal metabolism, and the site with the highest hydrochemical stability was the one where S. lapponum occurred naturally. The species composition and structure of the phytocoenoses at all study sites were characteristic of natural sites of the species and showed no disturbances caused by human impact. The microbiological analyses indicated normal soil processes. The hydrochemical and biocoenotic stability of the habitat, including the microbiological balance of the soil, which was free of pathogenic fungi, should have a positive effect on the condition of the reintroduced plants. Full article

Salix lapponum L. is a boreal relict species, threatened with extinction in Poland. An 80% decrease in the number of its stands was confirmed in the last half-century, so that to prevent the loss of downy willow, attempts were made to reintroduce this species in natural habitats. Micropropagation was chosen as a first stage of its active conservation. S. lapponum shoots were collected and disinfected with NaOCl, AgNO₃, or HgCl₂ or with a two-step disinfection with NaOCl and then placed on MS medium with BA 1 mg·dm⁻³ and IBA 0.1 mg·dm⁻³. Regenerated shoots were cultivated with addition of BA, KIN, or 2iP, alone or in combination with auxins, to find the highest multiplication rate. Inter-simple sequence repeat (ISSR) analysis and flow cytometric analyses were conducted on in vitro regenerated plants to check their genetic stability. Disinfection was quite difficult and the use of HgCl₂ was the most efficient. The highest multiplication rate was obtained in presence of KIN at 0.5 mg·dm⁻³ + IAA at 0.5 mg·dm⁻³. The analysis confirmed the genome size stability, which is in agreement with the results obtained by ISSR, revealing no somaclonal variation in plantlets and therefore allowing the use of the obtained plants for reintroduction. Full article