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1

Disorders of programmed cell death in differentiating tracheids and anatomical abnormalities of Pinus sylvestris wood in polluted environment

100%
Rusin A., Tulik M.
Polish Journal of Natural Sciences. Supplement
|
2003
|
tom 01
2
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Content available

Leaf blade structure and the tolerance of Acer negundo L. (box elder) to the polluted environment

63%
Dineva S. B.
Dendrobiology
|
2005
|
tom 53
11-16
Polluted air is a stress factor that contributes to the decline of urban trees. Air pollution may cause short-term (acute) damage, which is immediately visible and long-term (chronic) damage, which can lead to gradual tree decline. Long-term damage may predispose trees to other disorders. The impact of technogenic factors on the leaf’s anatomical structure of Acer negundo L. (Box elder) was studied. The thickness of the upper cuticle is increased when compared to those from an ecologically pure area. A change in the rate of mesophyll tissue is due to the enlargement of the palisade parenchyma. The thickness of lower epidermal cells is decreased. All changes of the leaf blade structure are significant and are in direction of increasing the xerophyte characteristics of the leaves. Box elder is native to much of temperate North America. This is a tree of lowlands and wet hardwood forests. As such, we can assume that the registered changes are adaptive responses of the tree to the contaminated environment and that the tree can be considered to be relatively tolerant.
3

Measuring operating parameters of agricultural machines working in a highly polluted environment

63%
Wieczorek A. N.
Electronic Journal of Polish Agricultural Universities. Series Agricultural Engineering
|
2014
|
tom 17
|
nr 3
4
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Content available

Influence of a heavy-metal-polluted environment on Viola tricolor genome size and chromosome number

63%
Slomka A., Siwinska D., Wolny E., Kellner K., Kuta E.
Acta Biologica Cracoviensia. Series Botanica
|
2011
|
tom 53
|
nr 1
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.
5

Reproduction of Vicia cracca L. in the polluted environment of the Legnica-Glogow Copper Basin [Poland]

63%
Izmailow R.
Acta Biologica Cracoviensia. Series Botanica
|
2000
|
tom 42
|
nr 2
The effects of stress conditions in a polluted environment on the reproductive processes of plants were studied for two successive years. Vicia cracca is a component of the spontaneous green belt at the base of a copper processing post-flotation waste reservoir (Żelazny Most, Legnica-Głogów Copper Basin, Silesia, Poland). Plants from the site were compared with plants derived from seeds harvested from the contaminated site which grew in non-polluted soil on an experimental plot near Cracow. Almost all of the studied flowers showed degenerative tapetal processes in ~50% of the anthers, starting simultaneously in various stages of meiotic divisions in the pollen mother cells. At the tetrad stage nearly 50% of the anthers contained wholly degenerated tetrads. Disturbances in meiosis increased the amount of degenerated pollen grains. The proportion of potentially functional pollen grains was 47% in 1997 and 56% in 1998; in the control material the corresponding proportions were 87% and 84% (1998 and 1999). Various kinds of developmental disturbances and degenerative processes eliminated some of the ovules from the seed production. The percentages of ovules forming seeds was 56% and 59% in successive years (85% and 87% in the control). Most of the disturbances and degeneration can be attributed to the combined negative impacts of specific environmental factors.
6

Changing settlement patterns in North-East Estonia - a region of polluted environment and political conflicts

63%
Marksoo A., Roosaare J.
Geographia Polonica
|
1995
|
tom 64
7
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Effect of polluted environment on the female and male strobili bearing of European Scots pine provenances

63%
Chalupka W., Rozkowski R.
Dendrobiology
|
2000
|
tom 45
Studies on female and male strobili production as well as on pollen production and viability were performed at a polluted (Luboń) and a control (Kórnik) sites. Female strobili bearing per tree and total length of male strobili produced per tree were significantly higher in Luboń than in Kórnik and the stand density and tree crown exposition to sunlight were likely responsible for that result. Percentage of pollen germination was not affected by any variables studied. Neither provenance nor provenance x site interactions were found.
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