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Is Viola tricolor L. from calamine waste heaps in the vicinity of Olkusz (Southern Poland) a metal-tolerant taxon?

100%

Kellner K. , Kuta E.

2005

tom 47

nr 1

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

70%

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.

Pollen heteromorphism in wild and ornamental pansies (Sect. Melanium, Violaceae)

61%

Slomka A. , Kuta E. , Pilarska M. , Kellner K. , Kawalec P. , Bohdanowicz J.

Acta Biologica Cracoviensia. Series Botanica. Supplement

2008

tom 50

nr 1

Was reduced pollen viability in Viola tricolor L. the result of heavy metal pollution or rather the tests applied?

61%

Slomka A. , Kawalec P. , Kellner K. , Jedrzejczyk-Korycinska M. , Rostanski A. , Kuta E.

Acta Biologica Cracoviensia. Series Botanica

2010

tom 52

nr 1

123-127

We used different tests to assess the effect of high soil concentrations of heavy metals on pollen viability in plants from metallicolous (MET) and nonmetallicolous (NONMET) populations. The frequency of viable pollen depended on the test applied: MET plants showed no significant reduction of pollen viability by acetocarmine, Alexander, MTT and X-Gal dye testing, but a drastic reduction of pollen viability in MET flowers (MET 56% vs 72% NONMET) by the FDA test. There was no correlation between pollen viability estimated in histochemical tests and pollen germination in vitro or in vivo. We discuss the terminology used to describe pollen viability as determined by histochemical tests.

Spin and lattice dynamics of La2/3Ca1/3MnO3 doped with 1% 119Sn

51%

Przewoźnik J. , Żukrowski J. , Chmist J. , Japa E. , Kołodziejczyk A. , Krop K. , Kellner K. , Gritzner G.

2004

tom Vol. 49,suppl.3

37-42

1 at.% 119Sn doped La0.67Ca0.33MnO3 compound was studied by Mössbauer spectroscopy, magnetization, AC susceptibility and resistivity measurements. Huge separation (66 K) of the transition temperatures from the ferromagnetic (FM) to paramagnetic (PM) state (TC) and from metallic to insulating state (TM-I) clearly shows that transition from FM metallic to PM insulator phase goes via FM insulator phase. The Mn lattice dynamics was studied by the relative changes of Lamb-Mössbauer factor f as a function of temperature. In the Debye approximation from the calculated ln(f/f0) values of the characteristic Debye temperatures (čD) were estimated for the FM (368(10) K) and PM (391(6) K) phases. No anomaly of -ln(f/f0) at TM-I and its rather spurious increase around TC was found. The 119Sn isotope as a local diamagnetic probe samples the transferred hyperfine field (Bhf) from its neighbour Mn magnetic moments and witnesses the dynamics of the Mn moments. Theoretical curve based on the molecular field theory was fitted to the experimental values of Bm hf ax and the value of the ordering temperature (TC * H 280 K) of Mn moments inside the large FM domains was estimated. It is much higher than the TC (172 K) obtained from magnetization measurement. The coexistence of FM and PM phases, which is evident from the shape of our 119Sn Mössbauer spectra, was confirmed for temperatures T e 150 K and indicates the inhomogeneous character of the magnetic transition.