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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Phenotypic plasticity of European beech (Fagus sylvatica L.) stomatal features under water deficit assessed in provenance trial

100%
Stojnic S., Orlovic S., Trudic B., Zivkovic U., von Wuehlisch G., Miljkovic D.
Dendrobiology
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2015
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tom 73
The results of research into leaf stomatal variability of five European beech provenances originating from Austria, Bosnia and Hercegovina, Germany, Romania and Serbia are presented in this paper. Aim of the study was to investigate how stomatal traits of provenances originating from different environments change in response to drought stress and to assess the phenotypic plasticity of the stomatal features investigated. The study was conducted during two different years, characterized by contrasting weather conditions (2010 and 2011). Two-way ANOVA revealed that provenances differ significantly in terms of stomatal density (SD), width of stomatal aperture (Wb), potential conductance index (PCI) and relative stomatal pore surface (RSPS), during both seasons. In a dry year (2011) all provenances significantly increased stomatal density by between 16.1% (Hasbruch – DE) and 21.9% (Cer – SRB). Guard cell length (LA) was not statistically different among provenances in either year (2010 and 2011), even though LA decreased in the dry year (2011) in all provenances. Reaction norms were steep in most of the parameters suggesting the possibility of a plastic response of provenances toward changes in soil water regime, influenced by the prevailing weather each year. Phenotypic plasticity indices were the highest in regards of SD, PCI and RSPS, indicating that these traits would be good candidates for improvement in breeding programs aimed at selection of drought resistant.
2

Phenotypic plasticity within Daphnia longispina complex: differences between parental and hybrid clones

100%
Pijanowska J., Bernatowicz P., Fronk J.
Polish Journal of Ecology
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2007
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tom 55
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nr 4
The mechanism that enables the coexistence of apparently very similar species is fundamental in understanding the diversity of natural communities. The ranges of reactions of the three Daphnia clones in the presence of toxic compounds and fish kairomones were studied in laboratory. The ranges were based on differences in body length, spine length and fecundity (number of eggs in a brood chamber) during first three reproductions. The ranges of reactions of the three clones differed dramatically. The range of D. galeata and D. hyalina hardly overlapped, while that of a D. galeata × hyalina hybrid clone was significantly broader than the ranges of either parental species. The observed diversity of ranges of reactions probably enables the coexistence of closely related species in the variable environment of natural lakes.
3

Phenotypic plasticity of microalgal cultures in culture collections: a geometric morphometric approach

100%
Neustupa J.
Oceanological and Hydrobiological Studies
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2005
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tom 34
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nr 3
4

Morphological and anatomical variability of isozymatically identified clones of Pinus mugo Turra

100%
Baczkiewicz A., Prus-Glowacki W.
Acta Biologica Cracoviensia. Series Botanica
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2005
|
tom 47
|
nr 2
This study examined the anatomical and morphological variability of 10 needle traits in isozymatically identified clones of three peatbog populations of Pinus mugo, focusing on variation within and between clones, and the relation between isozyme variation and morpho-anatomical characters of needles. In each peatbog there were clones exhibiting high and low plasticity of the anatomical and morphological traits studied. In general, three types of variation within clones were distinguished: (1) clones with ramets very similar to each other, (2) clones with extensive intra-clone variability, and (3) clones with intermediate variability. The differences in phenotypic variability within clones may be explained by differences in the reaction norm of ramets in particular clones and by somatic mutations. In respect to anatomical, morphological and isozymatic traits, clones from the same peatbog showed more similarity to each other than to clones from other peatbogs.
5

Comparative study of ecophysiological and biochemical variation between the Baltic and North Sea populations of the invasive soft shell clam Mya arenaria (L. 1758)

84%
Lasota R., Pierscieniak K., Miac J., Wolowicz M.
Oceanological and Hydrobiological Studies
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2014
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tom 43
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nr 3
6

Effect of soil moisture on morpho-anatomical leaf traits of Ranunculus acris (Ranunculaceae)

84%
Kolodziejek J., Michlewska S.
Polish Journal of Ecology
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2015
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tom 63
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nr 3
Leaf morphological and anatomical differences between two collection sites in central Poland were examined in tall buttercup Ranunculus acris. We hypothesized that the availability of soil moisture would affect leaf morphological and anatomical traits. The objective of this study was to examine the effect of soil moisture content on: leaf size, epidermal features and on a number of stomatal characteristics in populations of R. acris species. The plants were investigated at sites differing in soil moisture conditions (a dryer upper site and a wetter lower site). Relatively semi-dry and wet sites were identified by plant communities and soil moisture content. We found out that morphological and anatomical leaf traits of R. acris were significantly related to soil moisture content. Leaves from plants growing in the wet site were 26% smaller in size than those from the semi-dry site. The population with smaller leaf area had larger leaf perimeter and higher dissection index. The stomatal index of the leaves sampled in the semi-dry site was higher than that of the leaves sampled in the wet site. Greater leaf thickness in the semi-dry site was primarily the result of increased spongy parenchyma thickness. On the abaxial leaf surface epidermal cell density was significantly higher at the wet site implying more epidermal cells. On the adaxial leaf surface, however, epidermal cell density decreased when plants were exposed to the elevated soil moisture. The results may indicate that soil moisture content influences leaf anatomy and morphology of R. acris. Thus, all these leaf morphoanatomical traits provide a basis for R. acris to reduce water loss from leaves and to balance water use efficiency under reduced precipitation. The present study demonstrates that R. acris can maximize growth in habitats with a wide range of soil moisture availability and such information can be crucial for developing management strategies and predictive models of its spread.
7

Phenotypic plasticity in the greater mouse-eared bat in extremely different roost conditions

84%
Uhrin M., Kanuch P., Kristofik J., Paule L.
Acta Theriologica
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2010
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tom 55
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nr 2
153-164
Bats use various roost types with a wide spectrum of ecological features. The greater mouse-eared bat Myotis myotis (Borkhausen, 1797), creates nurseries in attics and caves in Central Europe. The stable low temperature and high humidity cave microclimate contrasts that of attics, which may alter species adaptations and life strategies. We analysed population characteristics (composition, body condition, parasite load, and immune response) and genetic relatedness of two proximal M. myotis populations. Age, sexual and parasite species composition were similar between the cave and attic sites. However, a significantly higher parasite load and body condition was detected in the post-partum females and juveniles of the cave colony (n = 263 bats from the cave, 231 from the attic), with the cave colony females having a significantly stronger immune response (n = 2 caves and 2 attics, 20 females per site). There was no evidence for genetic divergence between cave and attic populations (n = 3 caves and 3 attics, 24 females per site), indicating that different population characteristics are not genetically based and that M. myotis is an example of a species with rather unique phenotypic plasticity.
8

Adaptive changes in morphology of Daphnia filter appendages in response to food stress

84%
Bednarska A.
Polish Journal of Ecology
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2006
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tom 54
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nr 4
Morphological adaptations of Daphnia filtration apparatus in response to unsuitable food conditions are examined and set against earlier published data. To maximize food gathering under limiting food conditions, Daphnia can respond morphologically by plastic changes in the size and structure of its filter apparatus. Under low food quantity and/or poor quality, the area of Daphnia filter screen increases and the mesh size decreases.
9

Induced defence in the ciliate Euplotes octocarinatus is reduced when alternative prey are available to the predator

84%
Kolaczyk A., Wiackowski K.
Acta Protozoologica
|
1997
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tom 36
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nr 1
10
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The effect of oak-hornbeam diversity on flowering and fruiting of Impatiens parviflora DC.

84%
Piskorz R.
Roczniki Akademii Rolniczej w Poznaniu. Botanika-Steciana
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2005
|
tom 09
11

Cogradient plasticity of growth in montane and lowland larvae of Rana temporaria [L.] at two levels of temperature

67%
Jasienski M.
Polish Journal of Ecology
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2009
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tom 57
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nr 2
353-361
Direct environmental impact and microevolutionary pressure may both shape the phenotype by acting synergistically (cogradient) or antagonistically (countergradient). An experimental approach is therefore needed to determine which environmental challenges are responsible for the observed inter-population variation in a phenotypic trait and if such variation is adaptive. Rana temporaria L. larvae were reared in a factorial experiment, with two temperature regimes (differential of 6°C) and larvae originating from two source populations in Poland: a montane pond in the Babia Góra National Park (elevation 1025 m) and a lowland swamp near Warszawa (elevation 100 m). Populations did not differ in early larval growth rates or in the length of the larval period. In both populations, the early rates of development were higher and the larval period was expectably and substantially shorter at higher temperature. The montane larvae were heavier at metamorphosis than the lowland larvae, but significantly so only at the low temperature treatment. The observed patterns of responses partially conform to the cogradient model of phenotypic variation, in which both environmental and selective effects are mutually enhancing the differentiation of populations.
12

Is this a new species, hybrid or maybe phenotypic plasticity results? The role and significance of phenotypic plasticity of flowers in taxonomy of Dactylorhiya majalis (Rchb.) P. F. Hunt and Summerh. (Orchidaceae)

67%
Faltyn A., Jakubska-Busse A.
Acta Botanica Silesiaca
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2008
|
tom 03
In the paper we present the results of studies on the variability range of the flower colour, size and shape in D. majalis. The research was carried out in three populations, deliberately chosen so that to exclude the possibility of hybridisation with other orchid species. The obtained results confirm a wide range of phenotypic plasticity of a taxon, in extreme cases causing problems in species identification. The performed analyses demonstrate that the labellum index, similarly to the colour of the flowers and the shape and the pattern of labellum, have a wide range of individual variability, which makes it quite difficult to classify taxa within the genus.
13

Hatching asynchrony and brood reduction in Blue Tits Cyanistes caeruleus may be a plastic response to local oak Quercus robur bud burst and caterpillar emergence

67%
Stenning M. J.
Acta Ornithologica
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2008
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tom 43
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nr 1
97-106
Blue Tits exhibit extreme variation in clutch size and hatching asynchrony, which is the focus of this study. This paper reports an in-depth study of breeding Blue Tits showing that variation in Blue Tit hatching asynchrony can be explained by a number of phenological variables including particularly, date of bud burst in the local oak tree, which signals caterpillar emergence (34%), also date of first egg (14%) and female weight (8%). Hatching asynchrony explained 9% of the variation in brood mortality in this southern English population. Early incubation relative to clutch completion (incubation asynchrony) in Blue Tits explained 85% of the variation in hatching asynchrony, differs between years and advanced hatching in early and fledging in late laid eggs. Consequently, because fledging is usually synchronous, hatching asynchrony shortens the total time spent in the nest and explained 28% of the variation in nesting time from clutch completion to fledging. I present experimental evidence that brood reduction resulting from hatching asynchrony may be particularly adaptive towards the end of the breeding season, with 91% of the variation in the productivity of asynchronously-hatched broods being explained by, and increased with, date of hatching. About one fifth of birds delayed daytime incubation until after clutch completion, probably in wait for caterpillars to appear. Although the delay period was variable and extended total nesting time it always resulted in synchronous hatching. I propose that Blue Tits may have evolved plastic responses to environmental cues such as oak bud burst, which causes them to incubate at the optimum time to ensure maximum fledging success and chick fitness.
14

The influence of shadow created by adjacent plants on phenotypic plasticity of endangered species Trollius europaeus L. Ranunculacea]

67%
Kostrakiewicz K.
Polish Journal of Ecology
|
2009
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tom 57
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nr 4
625-634
The assessment of phenotypic plasticity expressed as the response to abiotic and biotic site factors is important for successful conservation of endangered and threathened species. In Poland one of the strictly protected plant requiring an active conservation is globeflower Trollius europaeus L. It is the perennial forb, consisted of numerous dark green, deeply cut basal leaves and generative shoots with flowers composed of several multi-ovulate carpels. The investigations of morphological traits of Trollius europaeus i.e. number and height of generative shoots and basal leaves as well as the production of flowers, multi-follicles and follicles at stem- and cluster levels, were carried out between 2005 and 2008 on two patches of Molinietum caeruleae localized in Kraków vicinity (Southern Poland) and having different height of litter and herb layer. The study plot labelled NS- “not shaded” (2 000 m²) was prevailed by perennials with delicate procumbent or erect stems, small-tussock grass or short rosetteforb species. The height of the tallest plant has not exceeded 98 cm, while the litter layer measured from 10 cm to 28 cm. The study plot named SH- “shaded” (6 000 m²) was characterised by presence of tall perennials as well as grass and sedges forming large compact tussocks. The tallest plants attained 186 cm, whereas the layer of litter reached from 18 cm to 42 cm. In NS plot -32 clusters were observed, whereas in SH plot 39 clusters occurred. In both populations, clusters were situated in close vicinity, forming large aggregations. The number of aboveground units per cluster in both populations were similar. The longer petioles (higher petiole average length), caused by maximization of light capture were noted in SH, than in NS plot. In SH plot higher sexual shoots were also noted as well as greater number of flowers per shoot. Such phenomenon presumably makes the plant more attractive for pollinators and thus pollen receipt and donation. The similar number of flowers and multi-follicles per cluster were observed in both populations, while the greater number of follicles was observed in NS, than in SH plot. Due to morphological plasticity established clusters of T. europaeus might presumably endure among the vegetation cover or adapt to new environmental conditions. It might be considered that making the gaps in vegetation cover and litter can be an effective way for active protection of Trollius europaeus populations.
15

Effects of post-cutting changes in site conditions on the morphology and phenology of naturally regenerated beech seedlings [Fagus sylvatica L.]

67%
Barna M., Schieber B., Cicak A.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 3
461-472
We studied the response in growth and phenology of naturally regenerated beech seedlings to changed ecological conditions over 14 and 19-years after cutting with different intensity. Five different types of stand densities were modelled: plot C – control plot – no cut, L – low intensity cut, M – medium intensity cut, H – high intensity cut and CC – clear cut, with 1, 8, 22, 53 and 100% of relative irradiation, and 66, 68, 78, 92 and 100% of through fall, respectively. We were focussing on tree height growth and leaf area. Our phenological observations were aimed at onset and course of two spring vegetative phenophases: bud-burst and leaf unfolding. Already in two-year-old beech seedlings we found significant differences in height growth; the differences in mean leaf area, however, were observed later. From the viewpoint of phenotypic plasticity, the height growth in beech seedlings represented more sensitive response to the environment than the leaf area. According to leaf area size and height growth in the beech seedlings on control plot, the stress conditions were indicated, primarily from the lacking light. With stand opening, the development of recruitment was getting better, and beginning with plot M the increase of seedlings height and leaf area became continuously related to the amount of radiation. The results of phenological observations showed that the spring phenophases in the seedlings start first on control plot. The start of spring phenophases on the clearcut was always observed the latest, even in comparison with the parent stand. Correlation analysis confirmed a significant correlation (P <0.05, r = -0.61) between the mean air temperature in March and April and start of the phenophase leafing in the individual years. Analysis of long-term research showed that the trend of leafing’s onset observed in course of 18 years was significant (P <0.05), manifested a shift towards earlier dates.
16

Simulated herbivory limits phenotypic responses to drought in Convolvulus demissus Choisy [Convolvulaceae]

67%
Quezada I. M., Gianoli E.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 3
Drought and herbivory are important stress factors for plants. When plants are subjected to any form of stress, phenotypic responses are elicited to reduce damage. Responses to drought include a decrease in leaf area and aerial biomass, and an increase in root/shoot ratio of biomass allocation. If plants are subjected to drought and herbivory at the same time, constrained responses are expected due to resource limitation. In a greenhouse experiment we analyzed the effect of simulated herbivory on the ability to respond to drought stress in seedlings of the Chilean perennial herb Convolvulus demissus (Convolvulaceae), which in natural populations may experience water deficit during dry summers as well as grazing by mammals. Plants subjected to drought showed the phenotypic responses theoretically expected. In contrast, plants subjected to a combined drought + herbivory treatment did not show those responses, being phenotypically similar to control plants. It is suggested that herbivory may limit responses to drought in C. demissus, hence magnifying the negative consequences on plant fitness of such abiotic factor.
17

The effect of salinity of freshwater crustaceans

67%
Grzesiuk M., Mikulski A.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 4
Recent advancing industrialization and urbanization have increased salt concentrations in formerly-freshwater habitats. Freshwater animals are being affected, especially those like crustaceans that are unable to emigrate to escape the problem. The effects of increased salinity, first observed at the molecular level, are found to extend to the levels of the individual, population, community and ecosystem. Crustacean morphology, behaviour and life histories may be influenced, with growth rate, and age and size at first reproduction, being disturbed, along with clutch and neonate size. Mortality rates are also elevated where the salt concentration is high, though susceptibility to salt differs both between species and between clones of the same species. The effect may be to modify the composition of crustacean assemblages in terms of the species and clones present.
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