Search Results (4)

Unique vertical column structures were constructed for the greening of a structure at the Botanical Garden of Vilnius University, in which a plant cover was formed using the turf rolls of semi-natural meadows that were wrapped on 197 columns, with each column consisting of three equal segments. By evaluating the species composition and the abundance of vegetation in the segments of the columns, we studied how this natural cover changes and what its survival potential is. During the five years of observation, 97 plant species were determined in total. Over time, the initial plant species of fertile soils were mostly replaced by ruderal, nitrophilous, and pioneer plants. Out of the 58 original species, 18 disappeared, while 39 new ones emerged. In the vegetation cover on the north exposition of the building, the original species composition declined faster. The most persistent species were ruderal short-lived Conyza canadensis, Melilotus albus, and Urtica dioica, and long-lived Elytrigia repens. As for vegetation classes, the initial plant communities of the Molinio-Arrhenatheretea elatioris vegetation class were partially replaced by the plant communities of the Koelerio-Corynephoretea canescentis and Artemisietea vulgaris classes; however, unformed plant communities finally became prevalent. All directions, including the north, east, south and west, were equally dominated by semi-shade- and semi-light-loving plant species, together with a less abundant representation of light-loving species. Meanwhile, an unexpected establishment of the light-loving annual Arabidopsis arenosa was observed on the least illuminated north exposition. Likewise, the perennial Festuca pratensis, which is particularly resistant to wintering, emerged and spread on all expositions. The vegetation in the vertical columns was dynamic, and the initial plant species significantly diminished in the five years; however, as new species took place, the columns remained sufficiently covered with a green carpet of plants. This study reveals the benefits of using semi-natural meadow turfs in vertical greening of buildings in the harsh climate of a 5b hardiness zone, which is accompanied by distressing climatic fluctuations during the vegetation season. Full article

Arabidopsis arenosa is a good candidate for phytoremediation due to its high tolerance to Zn and Cd as well as its accumulation ability. However, its small size and low biomass are the largest obstacles to applying it on a broad scale. The aim was to obtain polyploid specimens, which tend to have higher biomass to increase the accumulation and translocation capacity of heavy metals in this metal-tolerant plant. Doubled polyploids (octaploids) were obtained via indirect organogenesis on a ½ MS medium supplemented with 1 mg L⁻¹ TDZ, followed by rooting on the same medium without growth regulators. Callus tissue of a high endopolyploidy level (the (Ʃ>2C)/2C ratio over 2.5) obtained on seedling fragments on ½ MS supplemented with 2 mg L⁻¹ 2,4-D + 2 mg L⁻¹ BAP served as a source material. Among the regenerants successfully obtained (without using antimitotic agents), over half, regardless of the stage of regenerant development, were octaploid (54–78%; 2C DNA = 1.642 pg). Octaploids were not affected by ploidy or in vitro culture conditions; they were fully fertile, produced normal pollen (~97% of viability), and set seeds capable of germinating (78%). Their cell and organ size was affected by genome doubling resulting in longer stomata, bigger pollen grains, and flowers with a larger area and width in comparison with tetraploid regenerants and initial plants. The promising results of measurements of morpho-anatomical, physiological, and reproductive parameters indicate that, in the future, after passing tolerance tests, the obtained polyploids could be used in phytoremediation of metal-contaminated areas. Full article

Functional and structural adjustments of plants in response to environmental factors, including those occurring in alpine habitats, can result in transient acclimation, plastic phenotypic adjustments and/or heritable adaptation. To unravel repeatedly selected traits with potential adaptive advantage, we studied parallel (ecotypic) and non-parallel (regional) differentiation in leaf traits in alpine and foothill ecotypes of Arabidopsis arenosa. Leaves of plants from eight alpine and eight foothill populations, representing three independent alpine colonization events in different mountain ranges, were investigated by microscopy techniques after reciprocal transplantation. Most traits clearly differed between the foothill and the alpine ecotype, with plastic adjustments to the local environment. In alpine populations, leaves were thicker, with altered proportions of palisade and spongy parenchyma, and had fewer trichomes, and chloroplasts contained large starch grains with less stacked grana thylakoids compared to foothill populations. Geographical origin had no impact on most traits except for trichome and stomatal density on abaxial leaf surfaces. The strong parallel, heritable ecotypic differentiation in various leaf traits and the absence of regional effects suggests that most of the observed leaf traits are adaptive. These trait shifts may reflect general trends in the adaptation of leaf anatomy associated with the colonization of alpine habitats. Full article

The following review article collects information on the plant species Arabidopsis arenosa. Thus far, A. arenosa has been known as a model species for autotetraploidy studies because, apart from diploid individuals, there are also tetraploid populations, which is a unique feature of this Arabidopsis species. In addition, A arenosa has often been reported in heavy metal-contaminated sites, where it occurs together with a closely related species A. halleri, a model plant hyperaccumulator of Cd and Zn. Recent studies have shown that several populations of A. arenosa also exhibit Cd and Zn hyperaccumulation. However, it is assumed that the mechanism of hyperaccumulation differs between these two Arabidopsis species. Nevertheless, this phenomenon is still not fully understood, and thorough research is needed. In this paper, we summarize the current state of knowledge regarding research on A. arenosa. Full article