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1
Terrestrial Antarctic ecosystems in the changing world: An overview
100%
Chwedorzewska K. J.
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nr 3
263-276
2
Content available Recent rapid climate changes in Antarctic and their influence on low diversity ecosystems
100%
Chwedorzewska K. J.
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nr 17
EN
The geographic position, astronomic factors (e.g. the Earth’s maximum distance from the Sun during winter), ice cover and altitude are the main factors affecting the climate of the Antarctic, which is the coldest place on Earth. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. Climate changes are occurring throughout Antarctica, affecting three major groups of environmental variables of considerable biological signifi cance: temperature, water, UV-B radiation. Low diversity ecosystems are expected to be more vulnerable to global changes than high diversity ecosystems.
3
Zmiany w populacji ptaków i ssaków płetwonogich Antarktyki Zachodniej
63%
Korczak-Abshire M. , Chwedorzewska K. J.
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2013
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tom 62
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nr 3
4
Content available Metody oceny zmian genetycznych wywołanych starzeniem się nasion przechowywanych w bankach genów
63%
Chwedorzewska K. J. , Puchalski J.
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nr 6
5
Genetic and epigenetic variation in a cosmopolitan grass Poa annua from Antarctic and Polish populations
63%
Chwedorzewska K. J. , Bednarek P. T.
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tom 33
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nr 1
6
Human impact upon the environment in the vicinity of Arctowski Station, King George Island, Antarctica
63%
Chwedorzewska K. J. , Korczak M.
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tom 31
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nr 1
45-60
7
Content available Morfologiczne, cytologiczne i biochemiczne aspekty długotrwałego przechowywania nasion typu "orthodox"
63%
Chwedorzewska K. J. , Puchalski J.
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nr 6
8
Stezenie nutrientow w wodzie zasilajacej wybrane stanowiska trawy Deschampsia antarctica [King George Island, Antarctica]
63%
Nedzarek A. , Chwedorzewska K. J.
Folia Universitatis Agriculturae Stetinensis. Agricultura
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2004
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tom 93
299-304
9
Preliminary genetic study on Deschampsia antarctica, and their related species from genus Deschampsia
63%
Chwedorzewska K. J. , Nedzarek A.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
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2005
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tom 72
10
Studies on changes in specific rye genome regions due to seed aging and regeneration
51%
Chwedorzewska K. J. , Bednarek P. T. , Puchalski J.
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nr 2A
EN
The aim of this study was to identify the genetic changes in rye seeds induced by natural aging during long-term storage and successive regeneration cycles under gene bank conditions. Genomic DNA from four rye samples (cv. Dańkowskie Złote), varying in their initial viability and having gone through one or three reproduction cycles, were analysed using specific PCR targeting of a secalin locus, and various repetitive fragments defined by the R173 sequence. A statistical analysis of the band frequencies for both secalin and R173.3 primer pairs revealed no changes in their frequencies. Similar data on R173.1 demonstrated significant changes between samples of different initial viability showing a lack of a band of the expected length (987 bp) in progeny originating from low viability seeds lots. These changes were inherited even after three regeneration cycles. Our results may indicate that long-term storage that leads to loss of viability also generates heritable changes in the preserved germplasm. However, it remains to be discovered where these changes occur and whether they are connected with coding or with non-coding DNA regions.
11
Plantations of Convallaria majalis L. as a threat to the natural stands of the species: genetic variability of the cultivated plants and natural populations
51%
Chwedorzewska K. J. , Kosinski I. , Galera H.
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nr Suppl.1
12
AFLP-profiling of long-term stored and regenerated rye genebank samples
51%
Chwedorzewska K. J. , Bednarek P. T. , Puchalski J. , Krajewski P.
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nr 2A
EN
The aim of these studies was to analyse the genetic changes induced by natural aging during long-term seed storage of rye. For this purpose, the AFLP (Amplified Fragment Length Polymorphism) technique was applied. In the experiment, DNA variation was demonstrated in seven-day-old seedlings of four seed samples of cv. Dankowskie Zlote, showing different levels of viability following long-term storage. Among the 362 AFLP fragments analysed, 73 had significantly different frequencies in at least one of the series. Principle Coordinate Analysis (PCA) based on molecular data revealed differences between the progenies of naturally aged seed samples with variable initial viability. It was clearly shown that materials with low viability differed in structure from highly viable ones, and that the population changes exhibited in the first case are preserved through regenerations. Although changes that were observed for initially viable samples were not so significant, they still occurred - probably as a result of genetic shift.
13
Analiza zmian genetycznych wywolanych dlugoterminowym przechowywaniem i regeneracja ziarniakow zyta /Secale cereale/ z wykorzystaniem techniki PCR-specyficznego.
51%
Chwedorzewska K. J. , Bednarek P. T. , Puchalski J.
Działalność Naukowa PAN. Wybrane Zagadnienia
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2002
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tom 13
106-108
14
The morphological variability of Convallaria majalis L. in natural and cultivated populations in three regions of Poland
51%
Kosinski I. , Galera H. , Chwedorzewska K. J.
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2009
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tom 57
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nr 3
473-482
EN
Introducing indigenous plants into cultivation and breeding programs in order to obtain new taxa can create the undesirable effects and pose a real threat to natural populations. The main problem of our study was to assess whether the phenotypic characters might allow distinguishing cultivated Convallaria majalis from plants occurring in natural habitats. The range of phenotype variability of Convallaria majalis L. shoots from forests and gardens growing in different edaphic factors was studied in 2005–2006 in north (Gdańsk), central (Warsaw) and south (Cracow) regions of Poland. Ten or eleven forest locations and the same number of garden locations were designated in each region. The soil at the forest sites was poorer in phosphorus and calcium and more acidic than at the garden sites from which the cultivated plants were obtained. Thirty flowering shoots were collected from each study site. The numbers as well as size of flowers, size of racemes and leaves were investigated. The following hypotheses were formulated: (a) due to conscious and unconscious selection, cultivated plants should have more numerous and larger flowers and a longer inflorescence (these characters are most significant for the ornamental appearance of the plant) than plants growing in forests; (b) cultivated plants exhibit less phenotype variability than do natural populations. The forest plants from all the three regions together had, in comparison with garden plants, significantly shorter racemes with fewer flowers, a narrower and shorter perianth, and a longer lower leaf with a narrower and longer leaf blade. In the forest plants raceme length exhibited the highest variability while the lowest was noted in perianth length. More morphological differences were noted between the forest and garden plants than among those from the three different regions. The results obtained indicate that the level of variability in the studied characters was similar in forest and cultivated plants. A high level of variability in some morphological characters of lily of the valley probably stems from the high phenotype plasticity of this plant and the diversified biotope conditions in which it occurs. The significant differences between forest and garden plants could have been related to differences in habitat conditions.
15
High anatomical and low genetic diversity in Deschampsia antarctica Desv. from King George Island, the Antarctic
51%
Chwedorzewska K. J. , Gielwanowska I. , Szczuka E. , Bochenek A.
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2008
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tom 29
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nr 4
377-386
16
Content available Molecular variation of Antarctic grass Deschampsia antarctica Desv. from King George Island [Antarctica]
51%
Chwedorzewska K. J. , Bednarek P. T. , Puchalski J.
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tom 73
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nr 1
EN
Deschampsia antarctica Desv. plants collected on King George Islands (Antarctica) at two localities that differ in topographic and nutrition conditions exhibited morphological variation that differentiated plants of both locations. The molecular variation characteristic to individuals of both sites was tested using AFLP approach in order to verify whether morphological variation characteristic to the plants resulted from environmental factors or possibly from differences at the DNA level. Four primer pair combinations were used to generate 339 AFLP fragments, 132 of which were polymorphic and allowed evaluation of genetic relationships among D. antarctica individuals. Chi-square test revealed that only 12 signals were discriminative for the plants from both locations. Cluster analysis conducted on these AFLP fragments demonstrated that plants from the location rich in biogenes were more polymorphic than those from poor one. Our data suggest that the phenotypic variation specific to plants of both locations seem to be the result of adaptation to the environmental conditions like soil and moisture rather than reflect genetic differences.
17
Polarne ekosystemy lądowe w kontekście zmian klimatycznych
45%
Olech M. , Wegrzyn M. , Lisowska M. , Chwedorzewska K. J. , Slaby A.
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2013
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tom 62
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nr 3
18
Alien invertebrates transported accidentally to the Polish Antarctic Station in cargo and on fresh foods
45%
Chwedorzewska K. J. , Korczak-Abshire M. , Olech M. , Litynska-Zajac M. , Augustyniuk-Kram A.
Polish Polar Research
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2013
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tom 34
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nr 1
19
An analysis of fungal propagules transported to the Henryk Arctowski Antarctic Station
45%
Augustyniuk-Kram A. , Chwedorzewska K. J. , Korczak-Abshire M. , Olech M. , Litynska-Zajac M.
Polish Polar Research
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2013
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tom 34
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nr 3
20
Studies on genetic changes in rye samples [Secale cereale L.] maintained in a seed bank
45%
Chwedorzewska K. J. , Bednarek P. T. , Lewandowska R. , Krajewski P. , Puchalski J.
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nr 3
EN
The aim of this study was to identify genetic changes in rye seeds induced by natural ageing during long-term storage and consecutive regeneration cycles under gene bank conditions. Genomic DNA from four rye samples varying in their initial viability after one and three cycles of reproduction was analyzed by AFLP (amplified fragment length polymorphism) fingerprinting. Seven EcoRI/MseI primer combinations defined 663 fragments, and seven PstI/MseI primer combinations defined 551 fragments. The variation in the frequency of the seventy-four EcoRI/MseI bands was statistically significant between samples. These changes could be attributed to genetic changes occurring during storage and regeneration. However, the PstI/MseI fragments appeared to be uninfluenced by seed ageing, regeneration and propagation. A combined Principle Coordinate Analysis revealed differences between samples with different initial viability. We showed that materials with low initial viability differ in their response from highly viable ones, and that the changes exhibited in the former case are preserved through regeneration cycles.
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