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1

The role of polyploidy in moss evolution

100%
Przywara L., Kuta E.
Biological Bulletin of Poznań
|
2001
|
tom 38
|
nr 2
2

Pleurozium schreberi - on of the most variable bryophyte species

100%
Wachowiak M., Zielinski R.
Biological Bulletin of Poznań
|
2001
|
tom 38
|
nr 2
3

Signal exchange between cells during progamic phase in flowering plants

84%
Sniezko R.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2008
|
tom 50
|
nr 1
4

Somatic embryogenesis of the tree fern Cyathea delgadii: ploidy stability of embryo-derived sporophytes

84%
Tomiczak K., Pozoga M., Mikula A., Sliwinska E., Rybczynski J. J.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2014
|
tom 56
|
nr 1
5

Organization of club moss gametophytes and juvenile sporophyte populations in pine forests

84%
Rimgaile-Voicik R., Naujalis J. R., Voicikas A.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 4
Initial populations of club mosses were investigated in pine forests of southern Lithuania (ass. Cladonio-Pinetum and Vaccinio vitis-idaeae-Pinetum). Results show that populations of lycophyta gametophytes in some forest sites can be abundant (up to 500 individuals in a square meter). All juvenile populations were found in localities where recorded tree canopy cover was 30% or less. Localization of subterranean gametophyte populations was determined by juvenile club mosses. We mapped locations of all Lycopodium L. and Diphasiastrum Holub. juvenile sporophytes and gametophytes that occurred within three randomly selected and excavated 0.25 m² sample plots at four pine forest sites in different localities in southern Lithuania. The developmental stage of each individual was recorded. Eight out of twelve soil samples from four research localities contained subterranean gametophytes. In total 277 gametophytes and 124 juvenile sporophytes were recorded. The developmental stage and size of the gametophytes varied. Gametophytes were divided into six categories on the basis of external features. Spatial distribution of gametophytes and juvenile sporophytes were evaluated using a nearest neighbor analysis (NNA). Our results suggest that initial populations of gametophytes in pine forests are multi-aged and display a relatively stable degree of spatial aggregation. Greater aggregation occurred among juvenile sporophytes.
6

Apomixis in ferns. Alternation of generations without syngamy and meiosis

84%
Zenkteler E.
Acta Biologica Cracoviensia. Series Botanica et Zoologia. Supplement
|
1997
|
tom 39
|
nr 1
7
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Gametophyte and sporophyte of tree ferns in vitro culture

84%
Goller K., Rybczynski J. J.
Acta Societatis Botanicorum Poloniae
|
2007
|
tom 76
|
nr 3
Experiments had been carried out on gametophytes and very young fronds of sporophytes with application of Murashige and Skoog (1962) medium. The paper described the results of 15 years in vitro experiments on 16 species of tree ferns belonging to various genera: Blechnum, Cibotium, Cyathea and Dicksonia. Genus Cyathea was represented by: C. australis (R.Br.) Domin., C. capensis (L.f.) Sm., C. cooperi (F.Muell.) Domin, C. brownii Domin, C. dealbata (G.Forest) Sw., C. dregei Kunze, C. leichhardtiana (F.Muell.) Copel., C. robertsiana (F.Muell.) Domin., C. schanschin Mart., C. smithii Hook.f. and Cyathea sp. In case of genus Dicksonia only two species were introduced into our experiments: D. fibrosa Colenso and D. sellowiana Hook.. Taxa Blechnum was presented by B. brasiliense Desv. and Cibotium by C. glaucum (Sm.) Hook. and Arn. and C. schiedei Schltdl. and Cham.. The studied species presented various responses on culture conditions depending on the level of stage of development. Time required for spores germination differed between species and took from only a few to 16 weeks. Prothalium formations showed various types of growth presented by marginal meristems. For all investigated species long term gametophyte in vitro cultures was established. Mature gametophyte possessed functional antheridia and archegonia. Spontaneous fertilization helped to establish the culture of young sporophytes. For all species the ex vitro culture in greenhouse collection was established. Manipulation of sucrose content in the medium stimulated the multiplication of gametophytes, but its lack induced formation of gemmae. Apospory was observed when culture of very young fronds was extended for 6 months and new generation of gametophytes was developed. Finally, sporophytes of 12 species were obtained and they have been growing in our greenhouse.
8
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A new and fast method to obtain in vitro cultures of Huperzia selago (Huperziaceae) sporophytes, a club moss which is a source of huperzine A

67%
Szypula W. J., Mistrzak P., Olszowska O.
Acta Societatis Botanicorum Poloniae
|
2013
|
tom 82
|
nr 4
This study presents a protocol for a fast and effective in vitro axenic culture of Huperzia selago (Huperziaceae Rothm.) sporophytes, a club moss which is a source of huperzine A, an alkaloid of a considerable therapeutic potential extensively investigated for its uses as treatment for some neurodegenerative diseases. The proposed procedure allowed approximately tenfold shortening of the species developmental stages with the omission of the gametophyte stage while the sporophyte mass could be increased tenfold within a 6-month period. The cultures were established using vegetative propagules (bulbils) procured from sporophytes growing in the wild without degrading the habitats of this endangered plant species. Explants underwent surface and internal disinfection to eliminate the epiphytic and endophytic bacteria and fungi. In in vitro cultures, the optimum results were achieved using Moore (Mr) medium without growth regulators or supplemented with 0.015 mg/l IBA and 0.3 mg/l kinetin. These media ensured both viability of the propagules and their further development. The biomass growth index for H. selago sporophytes grown from propagules, determined at 3 months of culture (1 passage) on Mr medium with IBA and kinetin was 650%. At 6 months, the biomass growth index increased to 1114%. Vigorous growth of adventitious roots, especially on Mr medium with the addition of 0.25 mg/l NAA, and callus formation on shoot apices were observed. At 6 months of culture, some sporophytes obtained from the bulbils were used as the initiating material for shoot subcultures, which developed best on Mr medium with IBA and kinetin.
9
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Cytoembryology of infertile segregants of the hybrid Lupinus varius L. x L. digitatus Forsk

67%
Kazimierska E. M., Kazimierski T.
Journal of Applied Genetics
|
1995
|
tom 36
|
nr 3
In F₂, F₃ and F₄ generations of one hybrid line of Lupinus varius × L. digitatus, segregation into infertile and fertile plants in the ratio 3:1 was observed. Cytoembryological analyses showed that sterility was caused by irregularities in megasporocyte formation, in megasporogenesis and megagametogenesis. The following abnormalities lead to female sterility: no megasporogenic cells separated in nucelluses; in other nucelluses with megaspore mother cells, these cells underwent vacuolation and died before reduction division. In the megaspore mother cells, in which probably meiosis occurs, the megasporocyte division is irregular; a restitution nucleus is frequently formed after reduction division and such megasporocyte develops into an embryo sac. In 8-nucleate embryo sacs a change in the nucellus polarization was observed, while in rarely encountered embryo sacs the embryo cells underwent vacuolation and then died. Female sterility in the studied segregants is determined genetically, whereas sterilization of reproduction cells is a developing process throughout the period of sporocyte and female gametophyte formation.
10

On the phenology of Anthoceros agrestis [Anthocerotae, Anthocerotaceae], with special reference to Central Europe

67%
Bisang I.
Fragmenta Floristica et Geobotanica
|
1995
|
tom 40
|
nr 1
11

Homo- and heterophasis in the in vitro reproduction of Phyllitis scolopendrium [L.] Newm.

67%
Zenkteler E. K.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1993
|
tom 41
|
nr 3
12
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Equisetum telmateia Ehrh. morphotypes related to anthropogenic habitats

67%
Wrobel D.
Acta Societatis Botanicorum Poloniae
|
2003
|
tom 72
|
nr 2
The Giant Horsetail (Equisetum telmateia) is the only representative of Equisetum genus included in the list of strictly protected species. In Central and Western Europe the species is found in communities belonging to alliances: Alno-Padion and Calthion. With progressing destruction of these biotopes, one can observe the phenomenon of this species moving to the habitats extremely anthropogenic in character. Frequent and intensive observations of this phenomenon were conducted in the Jasło - Krosno Dale area in southern Poland in three anthropogenic localities. In these localities three interesting, irregular Equisetum telmateia morphotypes were found: fo. serotinum subfo. proliferum, fo. spiralis and a morphotype with branched shoot. The phenomenon of morphological plasticity of sporophytes is thought to be connected with the action of genes, which regulate the identity of developing plant organs and their distribution. These genes perform a superior part in relation to the system of growth regulators.
13

Micropropagation of Polypodium vulgare L. by rhizome explants

67%
Zenkteler E. K.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1995
|
tom 43
|
nr 2
14

Sporophytic lethality in lowland populations of Osmunda regalis L.in Poland

67%
Zenkteler E.
Acta Biologica Cracoviensia. Series Botanica
|
1999
|
tom 41
The genetic load of three lowland populations of Osmunda regalis was studied. The presence of deleterious mutations was reflected in disturbances in gametophyte development sequences and in the course of gametogenesis and fertilization. In sporophyte generation, sporophytic lethals were expressed in the zygotic, embryonic, postembryonic or juvenile stages, causing lethality of homozygous individuals originating from selfing. Heterozygous individuals were symptomless carriers of this genetic load.
15

Influence of site conditions on the diversity of endophytic fungi of fir clubmoss Huperzia selago (L.) Bernh. ex. Schrank et Mart

59%
Budziszewska J., Szypula W.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 4
The aim of the study was to assess the influence of environmental conditions on the composition of endophytic assemblages associated with fir clubmoss, Huperzia selago (L.) Bernh. ex Schrank et Mart. This clubmoss is a cosmopolitan species widely spread in Eurasia and North America, and its gametophytes and sporophytes are colonised by endophytic fungi. Plants for this study were collected in October 2004 and between April and October 2007 from seven European sites, differing in altitude, average annual precipitation, temperature and plant community. Endophytes were isolated on PDA medium (4% potato-dextrose agar) and identified through morphological observations. Different ecological indices were calculated for each site like colonization factor, Fisher’s alpha, Shannon’s diversity, Morista-Horn and Jaccard’s indices. Our results prove that altitude positively correlates with species diversity (Fisher’s alpha) and species richness (number of species). Moreover, the similarity assessed from Jaccard’s (0.66 for Larici-Piceetum sites) and Morista-Horn indices (0.77 for Juncetea trifidi sites) suggest the influence of plant community on fungal endophyte composition.
16

A comparative analysis of the reproductive biology of two populations of Pteris cretica

59%
Zenkteler E., Lijuan J.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
1999
|
tom 41
|
nr 1
17

Karyology of bryophytes

59%
Przywara L., Kuta E.
Polish Botanical Studies
|
1995
|
tom 09
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