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Intraspecific changes in genome size and chromosome number lead to divergence and species evolution. Heavy metals disturb the cell cycle and cause mutations. Areas contaminated by heavy metals (metalliferous sites) are places where microevolutionary processes accelerate; very often only a few generations are enough for a new genotype to arise. This study, which continues our long-term research on Viola tricolor (Violaceae), a species occurring on both metalliferous (Zn, Pb, Cd, Cu) and non-metalliferous soils in Western and Central Europe, is aimed at determining the influence of environments polluted with heavy metals on genome size and karyological variability. The genome size of V. tricolor ranged from 3.801 to 4.203 pg, but the differences between metallicolous and non-metallicolous populations were not statistically significant. Altered chromosome numbers were significantly more frequent in material from the polluted sites than from the non-polluted sites (43% versus 28%). Besides the standard chromosome number (2n = 26), aneuploid cells with lower (2n = 18–25) or higher (2n = 27, 28) chromosome numbers were found in plants from both types of site, but polyploid (2n = 42) cells were observed only in plants from the metalliferous locality. The lack of correlation between chromosome variability in root meristematic cells and genome size estimated from peduncle cells can be attributed to elimination of somatic mutations in generative meristem, producing chromosome-stable non-meristematic tissues in the peduncle.
Mineral forms in rhizosphere and bulk substrate were examined for selected plant species (Cardaminopsis arenosa, Calamagrostis epigeios, Deschampsia caespitosa, Festuca ovina, Silene vulgaris, Viola tricolor) growing spontaneously in the close vicinity of a tailings pond and in a zone of eolian transmission of waste particles. Samples of substrates and plant roots were taken from sites in the Bolesław orefield near Olkusz. The substrates together with plant roots were studied by scanning electron microscopy coupled with energy dispersive spectroscopy. Apart from quartz and carbonates, the most frequent mineral phases found were crystalline and amorphous Fe oxides, as well as primary Fe, Zn and Pb sulphides (marcasite, pyrite, sphalerite, galena). Hydrated Ca, Mg and Fe sulphates (gypsum, epsomite and melanterite) and other secondary minerals (smithsonite, cerussite, otavite, and Fe, K and Mg aluminosilicates) were found at larger concentrations in the rhizosphere than in bulk soil, suggesting that plant roots can change the mineral composition of the soil.
This study investigates the effect of high concentrations of Pb and Zn on biomass production and accumulation of both metals in zinc violets (Viola calaminaria and Viola guestphalica) and two species of violets indigenous to Poland (Viola lutea sudetica and Viola tricolor). The influence of the plants on soil pH also was assessed. The soil used in the experiments, containing 183 mg kg-1 Zn and 53.4 mg kg-1 Pb, was spiked with Zn and Pb at 1,000 mg/kg soil (Treatment 1) or Zn at 10,000 mg/kg and Pb at 1,000 mg/kg (Treatment 2). Zn concentrations were found to be higher in roots than in shoots in all investigated species. In zinc violets, Zn content in the soil correlated with Zn concentrations in plant tissue, both roots and above-ground parts. There was no such dependence among indigenous violets. Since all confirmed hyperaccumulators accumulate metals preferentially in shoots, with lower concentrations in roots, our results suggest that zinc violets should not be classified as Zn hyperaccumulators. V. l. sudetica occurs naturally on soils with low heavy metals content. Its roots accumulated the highest amount of Zn (6,498 mg/kg) observed in the current study with no toxic effects. Roots were able to change the soil pH, but the differences were not significant. V. l. sudetica and V. tricolor increased biomass significantly in Treatment 1 versus the control, but in Treatment 2 neither species differed in biomass from the control. In Viola guestphalica no influence of treatments on dry weight was observed. We suggest that zinc violets can be useful for phytorestoration of contaminated sites.
The qualitative and quantitative analysis of polycyclic aromatic hydrocarbons contamination in selected popular brands of fruit and herbal teas was performed using GC-MS method. Among all teas similar quality profiles of PAHs were observed. In all determined compounds 4 light PAHs (phenanthrene, anthracene, fluoranthene, pyrene) from the group of PAHs listed by EPA were predominant. From group of 15 PAHs, marked out for analysis by The UE Scientific Committee on Food, only benzo[a]anthracene, chrysene, 5-metylchrysene, benzo[b]fluoranthene and benzo[k]fluoranthene were stated, although, their levels were relatively low. Benzo[a]pyrene and the most carcinogenic PAHs, namely dibenzopyrenes, were not detected. Moreover, the GC-MS analysis revealed significant differences in contamination level of particular brands of teas among all fruit and herbal teas under investigation.
The main aim of the study was to evaluate the antioxidant activity and total polyphenols content in fifteen herbal plants, such as chamomile flower head, oak bark, St. John’s-wort herb, hawthorn flower, dog rose and elder fruits, lingonberry leaf, and many more. From the herbs both the water and methanolic extracts were prepared. The highest antioxidant activity and the highest polyphenols level were obtained for lingonberry leaves (1752.9 mg Trolox/g d.w. and 199.6 mg catechin/g d.w., respectively). The oak bark, St. John’s-wort herb, and flowers of hawthorn and elder were also a very valuable source of antioxidant compounds. It was demonstrated that, in contrary to water, methanol was more efficient solvent for extraction of antioxidant compounds from lingonberry leaf, lime flower, fruits of elder and doge rose, oak bark, flowers of hawthorn, St. John’s-wort herb and heartsease herb. Therapeutic activity of some examined herbs did not depend on antioxidant activity.
18
41%
Echa Leśne
|
1993
|
tom 18
|
nr 05
26
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