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1

The tetraploidy of Purkinje cells in the cerebellum in reference to the problem of polyploidy

100%
Kowalska E., Marcinkowski T.
Folia Histochemica et Cytobiologica
|
1997
|
tom 35
|
nr 2
2

Comparative cytogenetic study of some grass genera of the subfamily Pooideae in Iran

75%
Sheidai M.
Polish Botanical Journal
|
2008
|
tom 53
|
nr 1
15-28
3

Low base numbers and dysploidy in annual Helichrysum Mill. [Asteraceae: Gnaphalieae]

75%
Galbany-Casals M., Susanna A., Briones J. M.
Acta Biologica Cracoviensia. Series Botanica
|
2009
|
tom 51
|
nr 2
107-114
We report one new base number for Helichrysum, x = 5, found in the South African species H. indicum (2n = 10), and additional evidence for the recently documented x = 4 found in several South African species: H. litorale (2n = 8), H. spiralepis (2n = 8) and H. zwartbergense (2n = 8). Dysploidy is shown as an additional evolutionary trend within the genus, apart from polyploidy which is most extensive and documented. The association of dysploidy processes with the acquisition of an annual life cycle and adaptation to aridity is discussed for these species and other plant groups
4

The role of polyploidy in moss evolution

75%
Przywara L., Kuta E.
Biological Bulletin of Poznań
|
2001
|
tom 38
|
nr 2
5
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Improving growth indices and productivity of phytochemical compounds in lemon balm (Melissa officinalis L.) through induced polyploidy

63%
Talei D., Fotokian M. H.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2020
|
tom 101
|
nr 3
6

The effect of the ploidy level and genetic background of Sphagnum denticulatum on its morphology and ecological requirements

63%
Melosik I.
Oceanological and Hydrobiological Studies
|
2009
|
tom 38
|
nr 4
153-164
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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.
8

Chromosomal mosaicism on amniotic interphase nuclei detected by multiprobe FISH

63%
Constantinou M., Zajac E., Kaluzewski B.
Journal of Applied Genetics
|
2003
|
tom 44
|
nr 4
9

Various DNA content in myotube nuclei during myotomal myogenesis in Hymenochirus boettgeri [Anura: Pipidae]

63%
Daczewska M., Saczko J.
Folia Biologica
|
2003
|
tom 51
|
nr 3-4
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Nuclear morphology, polyploidy, and chromatin elimination in tissue culture of Allium fistulosum L.

63%
Joachimiak A., Ilnicki T.
Acta Societatis Botanicorum Poloniae
|
2003
|
tom 72
|
nr 1
The morphology of cell nuclei in callus obtained from root-tip meristems of Allium fistulosum L. (Monocotyledoneae, Alliaceae) was analysed. The most interesting phenomena observed in long-term callus culture were the different mechanisms of cell polyploidization, enlargement of telomeric segments of heterochromatin, and extensive chromatin elimination, associated with instability of nuclei size and DNA content. Protruding heterochromatin "spikes" were observed on the surface of some di- and polyploid nuclei. The presence of these spikes was connected with the formation of small heterochromatic micronuclei frequently found in the cytoplasm. It is suggested that these micronuclei are produced by direct elimination of heterochromatin from the interphase nuclei. Polyploid cells accumulated with each successive cell collection. The ploidy level attained by highly polyploid cells was 15C-220C. The shape of the nuclei and heterochromatin distribution suggest that polyploid nuclei in A. fistulosum tissue culture are produced by endoreduplication and by restitution cycles.
11

Structure and genetic organization of the polyploid macronucleus of ciliates: a comparative review

63%
Raikov I. B.
Acta Protozoologica
|
1995
|
tom 34
|
nr 3
12

Molecular cytogenetic analysis of genome structure in Chenopodium album complex

63%
Kolano B., Siwinska D., Maluszynska J.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
|
2005
|
tom 72
13

Regeneration of diploid and tetraploid plants of Arabidopsis thaliana via callus

63%
Fras A., Maluszynska J.
Acta Biologica Cracoviensia. Series Botanica
|
2003
|
tom 45
|
nr 2
Different explants from diploid and tetraploid plants of Arabidopsis thaliana ecotype Wilna were cultured in vitro on the same medium in the same conditions. The mode and capacity for regeneration and the ploidy level of regenerants were examined in eight callus lines. The explant responses to in vitro conditions depended on the ploidy level of donor plants and on the type of explant. Callus derived from leaves of tetraploid plants showed the highest ability to regenerate. Histological investigation showed that plants regenerated mostly through organogenesis and occasionally through embryogenesis. Somatic embryos were observed more frequently in callus derived from tetraploid plants. Regenerated plants were diploids, triploids and tetraploids. The majority of regenerated plants from callus of diploid origin were diploid, but diploids were also observed quite frequently among regenerants from callus of tetraploid origin.
14

Genetics of the loach, Misgurnus anguillicaudatus: recent progress and perspective

63%
Arai K.
Folia Biologica
|
2003
|
tom 51
|
nr Suppl.
15
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Karyotype evolution of the established RES [Ren Embryonis Suis] cell line

63%
Dziekanowska D., Scheller S., Rokicka A., Legowik E.
Journal of Applied Genetics
|
1995
|
tom 36
|
nr 2
The present paper refers to the previously reported cytogenetic studies of a cell line derived from an embryonic pig kidney and deals with chromosome alterations suddenly and spontaneously occurring in this line as structural rearrangements and polyploidy. Successive stages of karyotype evolution, domination of abnormal karyotype and this population dynamics are described.
16
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Seed vigor, photosynthesis and early growth of saplings of different triploid Betula families

51%
Mu H., Jiang J., Li H., Liu G.
Dendrobiology
|
2012
|
tom 68
Breeding scientists have given extensive attention to triploids in trees because of their importance to forestry. Consequently, creating and breeding triploids of good quality has become one of purposes of tree breeding. We chose two autotetraploids (Betula platyphylla, named Q10 and Q65) as female parents and eight hybrid diploids (B. platyphylla × B. pendula, named F1 – F8) as male parents to obtain progenies through controllable pollination, resulting in triploid progenies. Germination rate and germination energy of triploid seeds of Q65 were significantly higher (P < 0.01) than in triploid seed s of Q10. Triploid families with Q65 as female parent had a large quantity of saplings, whereas triploid families with Q10 as female parent had a small quantity of saplings. Triploid families with Q65 as female parent were generally superior in base diameter and height to base diameter ratio when compared to a diploid family. Q65×F3 was preliminarily recognized as the superior family. These results demonstrate that the female parent has a major influence on triploid progenies, although the male parent also has a small influence. The results provided a reference to build seed orchards of triploid birch trees, choose tetraploids as female parents and forecast triploid families of good quality.
17

Genetic constitution of parthenogenetic form of Polydrusus inustus [Coleoptera: Curculionidae] - hints of hybrid origin and recombinations

51%
Kajtoch L., Lachowska-Cierlik D.
Folia Biologica
|
2009
|
tom 57
|
nr 3-4
149-156
18

Karyotype, morphology, and reproduction ability of the Prussian carp, Carassius gibelio (Actinopterygii: Cypriniformes: Cyprinidae) from unisexual and bisexual populations in Poland

51%
Boron A., Szlachciak J., Juchno D., Grabowska A., Jagusztyn B., Porycka K.
Acta Ichthyologica et Piscatoria
|
2011
|
tom 41
|
nr 1
Background. The majority of the European populations of the Prussian carp, Carassius gibelio, consist predominantly of females reproducing by gynogenesis but include a small portion of males. Mechanisms for the occurrence of males in natural populations and their functions are still unclear. The aims of this study were to show the ploidy level by karyotype, some taxonomic characteristics by analysis of morphology, and the reproductive potential by histology of gonads of Prussian carp individuals of a certain age from two types of naturally existing unisexual triploid and a diploid-polyploid populations. Materials and methods. In total 31 specimens from three different populations inhabiting the Vistula River basin, the Baltic Sea watershed, have been analyzed. Kidneys were used to prepare chromosome slides using standard procedures. Air-dried slides were stained with Giemsa solution. For each fish, 23 metric characteristics of the body were measured. Selected meristic characteristics (external and internal) were determined. The gonads were fixed in buffered formalin or in Bouin’s solution; histological sections were stained with haematoxylin and eosin (HE). The developmental stages of germ cells and gonads were determined according to Rinchard and Kestemont and Billard. Results. All individuals of two populations were triploid females with high chromosomal variability from 150 to 160 chromosomes (and microchromosomes). Among individuals of the third population, males and females of 2n = 100 and one triploid male 3n = 160 (151–162) chromosomes were detected. The individuals from analyzed populations differed in the number of: branched rays in the dorsal fin, lateral line scales, serration in dorsal D and anal A fin rays, and vertebrae. Gonad histology of the ovaries indicated the females were mature at the age of 3. Testes morphology of diploids and one triploid male indicated their reproductive abilities. Conclusion. The results of the study confirmed the tendency to increase the number of males in C. gibelio populations. In several or some populations apart from diploid males a small number of fertile triploid males occur. High chromosomal variability within the females from unisexual populations may be influenced by their different mode of origin. The future research should be focused on karyological identification of other C. gibelio populations to explain the origin of triploid males and their role in reproduction.
19

Karyological investigations of selected angiosperms from Georgia and Azerbaijan

51%
Weiss-Schneeweiss H., Schneeweiss G. M.
Acta Biologica Cracoviensia. Series Botanica
|
2003
|
tom 45
|
nr 2
Chromosome numbers of eleven angiosperm species, five dicots and six monocots from Georgia and Azerbaijan are reported. The chromosome number of Cruciata coronata (Rubiaceae) is provided for the first time (2n = 22). Additionally, karyotypes are presented for five species, those of Danae racemosa (Ruscaceae), Paris incompleta (Trilliaceae), and Ruscus hyrcanus (Ruscaceae) for the first time. The new data are compared with previous karyological information, and both are discussed in a biosystematic context.
20

Holokinetic chromosomes of Luzula luzuloides [Juncaceae] in callus culture

51%
Madej A., Kuta E.
Acta Biologica Cracoviensia. Series Botanica
|
2001
|
tom 43
A long-term callus culture from Luzula luzuloides leaf meristem subcultured for over one year was examined cytologically. In the control material most of the mitotic cells (95.97%) represented diploid level and standard chromosomes in terms of length (2n = 12AL). Aneuploidy occurred with low frequency (4.03%), with somatic chromosome numbers 2n = 13, 14 resulting from partial agmatoploidy. Karyotype analysis of control material showed differences in chromosome length ranging from 4.94 µm to 3.19 µm in prometaphase, 3.54 µm to 2.54 µm in mid metaphase, and 2.81 µm to 1.88 µm in late metaphase. Callus cells exhibited a wide range of chromosome number variation (2n = 7-48), although a high percentage of cells (61.39%) represented the standard karyotype (2n = 12AL). Variability in chromosome number and karyotype structure was a consequence of chromosome fission (partial and total agmatoploidy), chromosome fusion (partial symploidy) as well as aneusomaty and polyploidy. There was no evident correlation between the frequency of structural and numerical chromosome variation and the duration of callus culture. The cells with modified karyotype appeared in particular collections.
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