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1
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Phyllotactic pattern formation in early stages of cactus ontogeny

100%
Gola E. M.
Acta Societatis Botanicorum Poloniae
|
2006
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tom 75
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nr 4
271-279
Representatives of the family Cactaceae are characterized by a wide range of phyllotaxis. To assess the origin of this diversity, early stages of phyllotactic pattern formation were examined in seedlings. The analysis of the sequence of areole initiation revealed intertribal differences. In seedlings from the Trichocereeae (Gymnocalycium, Rebutia) and Notocacteae (Parodia) tribes, two opposite cotyledonal areoles developed as the first elements of a pattern. Usually, next pair of areoles was initiated perpendicularly to cotyledonal areoles, starting the decussate pattern. This pattern was subsequently transformed into bijugate or into simple spiral phyllotaxis. In seedlings from the Cacteae tribe (Mammillaria and Thelocactus), cotyledonal areoles were never observed and the first areoles always appeared in the space between cotyledons. It was either areole pair (mainly in Mammillaria), starting a decussate pattern, or a single areole (mainly in Thelocactus) quickly followed by areoles spirally arranged, usually in accordance with the main Fibonacci phyllotaxis. Differences in the initial stages of pattern formation do not fully explain the phyllotaxis diversity in mature cacti. Only two, the most common phyllotactic patterns occurred in the early development of studied seedlings, i.e. the main Fibonacci and the decussate pattern. Discrepancy in the range of phyllotactic spectra in seedlings and in mature plants suggests that phyllotaxis diversity emerges during further plant growth. Initial phyllotactic transformations, occurring already in the very early stages, indicate great plasticity of cactus growth and seem to support the hypothesis of the ontogenetic increase of phyllotaxis diversity due to transformations.
2

Towards understanding morphogenetic mechanisms in early land plants

100%
Gola E. M.
Biological Letters
|
2005
|
tom 42
|
nr 2 Spec.Vol.
3

Morphogenesis at the shoot apex of Huperzia Bernh.

88%
Gola E. M.
Acta Societatis Botanicorum Poloniae
|
2010
|
tom 79
|
nr Suppl.1
4
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Vascular structure contributes to shoot sectoriality in Selaginella kraussiana

63%
Gola E. M., Jernstedt J. A.
Acta Societatis Botanicorum Poloniae
|
2016
|
tom 85
|
nr 3
Selaginella species are characterized by regular anisotomous dichotomous divisions of the shoot apical meristem, giving rise to two new axes (branches) which differ in size. A vital process is the formation of vascular connections, which enables continuous communication and consequent functional and developmental integration of a plant during branching. Here, we present the sequence of developmental changes in the vascular system of Selaginella kraussiana related to dichotomous branching. Stem vasculature in Selaginella kraussiana consists of two meristeles which change in arrangement during shoot development. Using dye tracers, we documented developmental functional isolation of meristeles associated with the specific structure of the stelar system, which results in a spatiotemporal sectoriality of the shoot. We discuss sectoriality in terms of possible significance for shoot development.
5
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Diversity of phyllotaxis in land plants in reference to the shoot apical meristem structure

63%
Gola E. M., Banasiak A.
Acta Societatis Botanicorum Poloniae
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2016
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tom 85
|
nr 4
Regularity and periodicity in the arrangements of organs in all groups of land plants raise questions about the mechanisms underlying phyllotactic pattern formation. The initiation of the lateral organs (leaves, flowers, etc.), and thus, their spatio-temporal positioning, occurs in the shoot apical meristem (SAM) and is related to the structure and organogenic activity of the meristem. In this review, we present some aspects of the diversity and stability of phyllotactic patterns in the major lineages of land plants, from bryophytes to angiosperms, in which SAM structures differ significantly. In addition, we discuss some of the possible mechanisms involved in the formation of the recurring arrangement of the lateral organs.
6
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Morphological variability of Helleborines. I. Diagnostic significance of morphological features in Epipactis helleborine (L.) Crantz, Epipactis atrorubens (Hoffm.) Besser and their hybrid, Epipactis x schmalhausenii Richt. (Orchidaceae, Neottieae)

63%
Jakubska-Busse A., Gola E. M.
Acta Societatis Botanicorum Poloniae
|
2010
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tom 79
|
nr 3
The comparative analysis of leaf morphology was performed in E. helleborine (L.) Crantz, E.atrorubens (Hoffm.) Besser, and their interspecific hybrid, Epipactis ×schmalhausenii Richt. The aim of this research was to find out features that would be useful in the taxonomy of the genus Epipactis, and particulary their taxa of hybrid origin. In course of the studies special attention was paid to leaf morphology, mostly to their margins, presence of papillae, their shape and size, and to leaf structure. The thickness of the leaf blades manifested by number of spongy mesophyll cell layers, size of vascular bundles and the level of leaf sclerification were compared in the hybrid and both parental species. In E. helleborine and E. atrorubens the analyzed features were highly variable, especially in the former species, which is characterized by wide phenotypic plasticity. Morphological and anatomical features in E. ×schmalhausenii showed a transitional character to the parental species. Our results suggest that a single feature can not be of taxonomic value, but the combination of different traits has to be considered when distinguishing parental and hybrid taxa.
7
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It is worth checking old data – validation of Asplenium onopteris L. presence in the most northeastern sites in Europe (Sudetes, SW Poland)

51%
Szczesniak E., Gola E. M., Jedrzejczyk I.
Acta Societatis Botanicorum Poloniae
|
2017
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tom 86
|
nr 4
In Poland, isolated serpentine rocks are exclusive habitats of some Asplenium species, reaching here their north or northeastern border range. One of them was Asplenium onopteris, a diploid European species native to Mediterranean and Atlantic areas. Since the nineteenth century, Polish out-of-range sites of A. onopteris have been quoted in literature without critical verification. Thus, to verify occurrence of this species in Poland, we analyzed the nuclear DNA content and micromorphological features as well as critically reviewed the literature data. We proved that all individuals from Polish populations resembling A. onopteris were tetraploids and should be classified as A. adiantum-nigrum. In addition, we validated a taxon silesiacum reported as co-occurring with A. onopteris. The proposed diagnostic features are insufficient to indisputably delimit this taxon, and distinguishing it as a separate unit is not justified. Analyses of the DNA content revealed also the presence of a triploid A. ×centovallense, a new hybrid for Polish flora.
8

Changes in accumulation of heteroplasmic mitochondrial DNA and frequency of recombination via short repeats during plant lifetime in Phaseolus vulgaris

51%
Woloszynska M., Gola E. M., Piechota J.
Acta Biochimica Polonica
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2012
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tom 59
|
nr 4
 Recombination via short repeats in plant mitochondrial genomes results in sublimons - DNA molecules with a copy number much lower compared to the main mitochondrial genome. Coexistence of stoichiometrically different mitotypes, called heteroplasmy, plays an important evolutionary role, since sublimons occasionally replace the main genome resulting in a new plant phenotype. It is not clear, how frequency of recombination and sublimon production is regulated and how it is related to changes in the quantity of the main genome and sublimons. We analyzed the accumulation of two recombining main genome sequences and two resulting sublimons in apical meristems, undifferentiated tissues and leaves of different age of Phaseolus vulgaris. Copy numbers of the main genome sequences varied greatly depending on tissue type and organ age while accumulation of sublimons remained much more stable. Although the overall accumulation of plant mtDNA decreased with the leaf age, the quantity of sublimons increased relative to the main genome indicating a higher frequency of recombination via the short 314 bp repeat. Recombination was symmetrical in young developing leaves while in senescent tissues it shifted towards asymmetric events resulting in overrepresentation of one product. We propose that during plant lifetime replication and recombination frequencies change oppositely sustaining heteroplasmic compositions of the genome, which are favorable for inheritance and maintenance of complex plant mtDNA.
9
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Lykopodiofity Polski Lycopodiales, Selaginellales, Isoëtales

51%
Szczesniak E., Gola E. M., Zenkteler E.
Monographiae Botanicae
|
2023
|
tom 110
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