Wyniki wyszukiwania

1

Controversy around apomixis

100%

Czapik R.

Acta Biologica Cracoviensia. Series Botanica

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2000

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tom 42

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nr 2

Three problems are discussed in the present article: the currently changing meaning and range of the term "apomixis," opinions on the normality of apomictic processes, and the relation between vegetative and apomictic reproduction. The differences in opinion on these matters reflect the authors’ subjective views, which cannot be avoided in dealing with complex phenomena that are difficult to manipulate experimentally. However, the increase in the number of synonyms that can be observed in the current literature is not useful in discussions and does not make statements easier to interpret. Thus, special attention should be paid to the precise use of terminology in discussions and articles on apomixis and related processes.

2

Niewykorzystane mozliwosci rozmnazania wegetatywnego roslin

75%

Czekalski M.

Prace Ogrodu Botanicznego Uniwersytetu Wrocławskiego

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1999

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tom 05

325-347

3

Controversy around apomixis

75%

Czapik R.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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1999

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tom 41

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nr 1

4

Reproduction of Primula veris L. plants in populations from natural localities

75%

Morozowska M.

Herba Polonica

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2004

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tom 50

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nr 3-4

The reproduction ability of Primula veris L. plants was described on the basis of six-year observations on permanent plots in populations from natural localities. Cowslip individuals in different life stages were mapped according to topographical distribution. The vegetative multiplication symptoms of the plants were also recorded. The mean survival rate of seedlings to the juvenile stage was similar in both populations, amounting to about 16.5%. The highest survival rate was found for juveniles (44.3-57.6%) and immature (31.4-48.6%) individuals, while the lowest number of individuals turned from the virginile into the generative stage (2.2-5.7%). The efficiency of the generative reproduction measured by the ratio of the number of generatively recruited flowering plants to the observed number of seedlings was 0.22-0.42%, depending on the population.

5

Morphological and genetical variability of Rubus hirtus [Waldst. and Kitt.] plants under partly open forest canopy

63%

Gazda A., Szwagrzyk J., Nybom H., Werlemark G.

Polish Journal of Ecology

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2007

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tom 55

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nr 1

Blackberries growing in forests regenerate mainly in a vegetative way; however, detailed studies have shown substantial variability in performance of Rubus individuals. The main problem is if the differences among plants are genetically based, or are due to site heterogeneity? This study was aimed at determining 1) how large are the differences in performance of individual plants and how persistent they are during consecutive years, 2) how much of that variability can be explained by the local environmental conditions, especially the intensity of competition among plants, and whether the performance of individual plants is related to their genetic characteristics. In a partially cut mature beech forest in Western Carpathians 35 randomly chosen individuals of Rubus hirtus (Waldst. & Kitt.) were tagged and measured each year for 9 years. Ten largest and ten smallest individuals were selected for genetic analysis. Mean size of individual plants differed between consecutive growing seasons, but the overall size ranking was quite consistent throughout the entire period of study. Analysis of environmental variables: relative light intensity and local abundance of potential competitors explained about 24% of the differences in individual plant performance. In the genetic analysis the five primers were applied to analyse all 20 samples. The five primers produced 10 polymorphic bands, showing a high variability. Only a few samples displayed identical band patterns, indicating either vegetative propagation or apomictic origin. Distribution of the results of Spearman’s rank correlation of plant size among genetically related individuals did not differ significantly from the distribution of rank correlation coefficients in the entire sample. In the analysed population genetical affinity did not seem to correlate with the performance of Rubus hirtus.

6

Bud banks of two dominant grass species and their roles in restoration succession series of a flooded meadow

51%

Li H., Yang Y., Zhao Y.

Polish Journal of Ecology

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2012

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tom 60

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nr 3

The primary goals of this study were to quantify the composition and size of bud banks and to evaluate the roles of bud banks of main dominant species Leymus chinensis (Trin.) Tzvel. and Carex duriuscula C.A. Mey. in population maintenance over a 2-year period. The four experimental plots were in early, early-mid, middle and late seral stages of a flooded restoration succession after they had approximately 12, 10, 8, and 6 months’ flood durations in the Songnen meadow, China. Five quadrats (each 0.25 ´ 0.25 m in area and 30 cm deep) were each sampled in four seral spots. The differences of L. chinensis and similarity of C. duriuscula in bud bank characteristics persisted in the studied seral stages from year to year. In each seral stage, rhizome buds comprised most of the L. chinensis bud banks in 2003; in 2004, juvenile tillers predominated. Rhizome buds consisted of the majority of C. duriuscula bud banks throughout the study period. The bud densities of L. chinensis and C. duriuscula experienced a significant linear increase with the increase of tiller density at different seral stages each year, but the slopes of these relationships in L. chinensis were higher than those in C. duriuscula. The total bud densities of C. duriuscula showed a significant linear decrease corresponding to the increase of those of L. chinensis from the early to the late seral stage in 2003 and 2004. Bud banks are vital for population maintenance and the number of bud banks is a good predictor of population dynamics.

7

Patterns of genetic diversity in populations of Filipendula ulmaria (L.) at different stages of succession on a meadow abandoned for 30 years

51%

Falinska K., Lembicz M., Jarmolowski A., Borkowska L.

Polish Journal of Ecology

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2010

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tom 58

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nr 1

Genetic diversity and spatial variation of two populations of Filipendula ulmaria (L.) were analysed at the initial stage (macroforbs) and the late succession stage (forest community) during a 30-year succession on the abandoned meadows in Białowieża National Park. The study demonstrated a high level of genetic diversity in both populations (D = 0.86 and D = 0.79 in the population at the initial and late succession stage, respectively). Significant genetic differentiation was observed at the cross-population level (FST = 0.008, P <0.001). Among 303 ramets in the population at the initial stage 261 genotypes were detected, of which 24 were clonal, and the remaining (237) were unique (91%). In the population at the late succession stage 92 genotypes were detected among 116 ramets of which 10 were clonal, and 82 unique (89%). The results did not confirm a hypothesis that the low level of the population’s genetic diversity should be expected at the late succession stage. Additionally, the study demonstrates that the prolonged clonal spreading does not always result in genetic monotony of a population. It has been demonstrated that the high level of genetic diversity in the population of clonal species F. ulmaria could be the result of temporal changes in life history traits of long-lived genets. The formation of gaps caused by the disintegration of senile genets and the permanent recruitment of seedlings over 30 years of population development reinforce the appearance of new genets. This process was reflected in both populations by the domination of unique genets and spatial pattern of genotypic diversity.

8

Genetic variation of the haploid moss Pleurozium schreberi [Musci, Hylocomiaceae] from Poland

51%

Wachowiak-Zielinska M., Zielinski R.

Fragmenta Floristica et Geobotanica

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1995

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tom 40

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nr 1

9

Structure, dynamics and population biology of Dentaria glandulosa [Cruciferae]. III. Effectiveness of generative and vegetative reproduction

51%

Tumidajowicz D.

Polish Botanical Studies

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1995

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tom 10

10

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The effect of dominant species on numbers and age structure of Iris sibirica L. population on blue moor-grass meadow in Southern Poland

51%

Kostrakiewicz K.

Acta Societatis Botanicorum Poloniae

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2007

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tom 76

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nr 2

Two populations of Iris sibirica, a clonal species protected by law in Poland, occurring in patches of Molinietum caeruleae, of similar floristic composition although with different dominant species, were studied. In the Stanisławice locality, species with a high competitive potential prevailed, contrary to the Opatkowice locality, where the species of low competitive potential dominated. It was established that vegetative propagation ensures the continued presence of populations in both localities, although the proximity of plants with high competitive potential limits the vegetative propagation of ramet clusters of Iris sibirica. Despite the high level of seed production, the recruitment of seedlings in both patches is possible only in artificially created gaps. The field observations support the conclusion that creating gaps allowing for germination of seeds and development of seedlings, as well as eliminating expansive neighbours allowing proliferation of ramet clusters of Iris sibirica, is an affective way of protecting populations of this species.

11

Polymorphism of sexual and somatic embryos as an evidence of their resemblance

51%

Batygina T. B., Zakharova A. A.

Bulletin of the Polish Academy of Sciences. Biological Sciences

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1997

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tom 45

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nr 2-4

Ograniczanie wyników

Controversy around apomixis

Niewykorzystane mozliwosci rozmnazania wegetatywnego roslin

Controversy around apomixis

Reproduction of Primula veris L. plants in populations from natural localities

Morphological and genetical variability of Rubus hirtus [Waldst. and Kitt.] plants under partly open forest canopy

Bud banks of two dominant grass species and their roles in restoration succession series of a flooded meadow

Patterns of genetic diversity in populations of Filipendula ulmaria (L.) at different stages of succession on a meadow abandoned for 30 years

Genetic variation of the haploid moss Pleurozium schreberi [Musci, Hylocomiaceae] from Poland

Structure, dynamics and population biology of Dentaria glandulosa [Cruciferae]. III. Effectiveness of generative and vegetative reproduction

The effect of dominant species on numbers and age structure of Iris sibirica L. population on blue moor-grass meadow in Southern Poland

Polymorphism of sexual and somatic embryos as an evidence of their resemblance