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Role of phenotypic plasticity, genetic and epigenetic differentiation in ecophysiological traits of Festuca rubra L. in response to climate change
Koláříková, Veronika ; Münzbergová, Zuzana (advisor) ; Schnablová, Renata (referee)
Understanding the ability of species to respond to climate change is essential for prediction of their future distribution. When migration is not adequate, reaction via phenotypic plasticity and/or genetic/epigenetic adaptation is necessary. The main aim of this study is to determine mechanisms of response to climate change in dominant grass species Festuca rubra. The study used reciprocal transplant experiment with growth chambers simulating different climatic conditions. Original localities in western Norway represent factorially crossed gradients of temperatures and precipitations, thus it was possible to study the effect of temperature and moisture separately as well as combined. In first part of the experiment, plastic responses were separated from genetic differentiation. To do this, plants with different genotypes from original localities were transplanted to growth chambers set to simulating temperature and moisture course in the four extreme localities (wettest and driest combined with warmest and coldest). After five months, ecophysiological photosynthetic-related traits were measured. These traits are important for species ability to adapt and maintain high fitness and thus they are essential for plants function. Specifically, it was net photosynthetic rate (PN), fluorescence of...
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Phenotypic variability and evolutionary relationships among populations of Primula elatior along an altitudinal gradient
Konečná, Veronika ; Kolář, Filip (advisor) ; Mandák, Bohumil (referee)
Primula elatior represents a promising model for addressing the role of phenotypic plasticity vs. genetic basis of traits in populations differentiated along altitudinal gradients. Phenotypic plasticity is mainly exhibited by the extensive variability of the leaves. Genetic structure of P. elatior populations has been poorly studied so far, the first insights suggested potentially large intraspecific genetic variation. Therefore, the first aim of this study was to reveal the genetic structure as well as morphological and cytological variation of P. elatior populations in the central Europe and compare those to another two intraspecific taxa from the southeastern Europe. Further, I selected three target mountain regions to address the role of altitudinal differentiation for structuring genetic diversity. Finally, I evaluated the status of the putative endemic species Primula elatior subsp. corcontica from the Krkonoše Mts. Microsatellite analyses, multivariate morphometrics and flow cytometry were employed to evaluate variation of P. elatior populations. I identified six major genetic groups by genotyping 12 nuclear microsatellite loci in the study area of central and southeastern Europe with the clear separation of subp. intricata. Focused on the central Europe, three well-defined genetic groups...
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Transgenerational effect of nutrient treatment on progeny of an apomitic plant
Vlk, Lukáš ; Mráz, Patrik (advisor) ; Skálová, Hana (referee)
Environmental conditions can influence epigenetic variability of clonal organisms. These environmentally induced changes have potential to persist in following generations. In theory, this transgenerational memory could allow clonal (and especially apomictic) plants to partly compensate reduced genetic variability and could enhance adaptative ability of apomictic populations. According to Muller's ratchet model, asexual organisms amass deleterious mutations, which could lead to their extinction. Possible transgenerational memory could partly compensate for this. It could also account for longtime survivorship of asexual organisms in environment. This thesis deals with transgenerational memory of triploid apomictic populations of Hieracium alpinum, with completely missing sexuality and thus genetically uniform offspring. Transgenerational effect in Hieracium alpinum was studied on clonal lineages originated from 5 populations (Norway, Austria, Bosnia and Herzegovina and Slovakia). Seeds were planted in cultivation experiment I in 3 treatments (control, added nutrients, added salicylic acid) and vegetative and generative traits were measured. Plants responded to nutrient addition but not to salicylic acid. Treatment with nutrient addition increased biomass, number of leaves and SLA (specific leaf...
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Influence of maternal effect on body size evolution in geckos
Kubát, Jan ; Kratochvíl, Lukáš (advisor) ; Frýdlová, Petra (referee)
In this diploma thesis has been tested potential of maternal influences on body growth at two model groups of geckos with large interspecific body size variability. The effect of egg manipulation to hatchling size was proved to be significant for hatchlings at both model species Paroedura picta and Goniurosaurus lichtenfelderi. However, in adult animals, there were no more significant body size differences caused by egg manipulation. It leads to conclusion that both species of geckos have compensatory growth and its adult size is likely to be primarily genetically determined. Key words: maternal effect, egg manipulation, body growth, allometric engeneering, Paroedura picta, Goniurosaurus lichtenfelderi
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Plant adaptation to climate change
Koláříková, Veronika ; Münzbergová, Zuzana (advisor) ; Sklenář, Petr (referee)
Climate change represents important selective force for plants. They have to deal with this change otherwise they are facing the risk of extinction. Understanding the mechanism which plants use to avoid the risk is essential for effective conservation of biodiversity. The climate change can exceed the tolerance of plants to abiotic factors. The plants can react to the changes by migration, phenotypic plasticity, evolutionary adaption or by a combination of these strategies. Phenotypic plasticity and evolutionary adaption are manifested by a change of physiology, morphology and/or phenology of plants. This work summarizes the findings of these ecological and evolutionary strategies and also presents methods used for studying species response to climate change. Powered by TCPDF (www.tcpdf.org)
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Phenotypic plasticity of smooth muscle cells
Misárková, Eliška ; Zicha, Josef (advisor) ; Pácha, Jiří (referee)
Vascular smooth muscle cells display a certain level of phenotype plasticity. Under specific conditions fully differentiated cells are able to undergo dedifferentiation and to restart growth and proliferation. An organ culture method is a useful technique for the analysis of dedifferentiation of vascular smooth muscle cells, because it provides an opportunity for studying the changes in cell phenotype. The aim of this study was to investigate the basic contractile characteristics in rat femoral arteries cultured for different time periods (from one to three days). In addition, the effects of fetal bovine serum (FBS), that contains various growth factors and other biological active molecules, on contractile function were studied. We also tried to attenuate cell dedifferentiation by lowering the calcium influx, because calcium is an important second messenger participating in cell growth and proliferation. To achieve this goal we used cultivation with nifedipine, a voltage-dependent calcium channel inhibitor. The cultivation without FBS slightly decreased arterial contractility, whereas the cultivation with FBS decreased arterial contractility considerably. The major change in contractility of arteries cultivated with FBS occurred approximately within 24 hours of cultivation. The cultivation with...
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The effect of urbanization on life-history strategies in birds
Houšková, Karolína ; Sedláček, Ondřej (advisor) ; Poláková, Simona (referee)
Urbanisation process is recently a wide-spread process that causes high-impact environmental transformation. Habitats affected by urbanization tend to change substantially and ongoing changes influence organisms living in this environment. Urban environment modifies many abiotic conditions (e.g. temperature, artificial light and noise) and biotic factors (e.g. food supply, parasite prevalence, predation pressure) in comparison to natural habitats. In this manner, especially urban bird populations have recently gained broad attention by an increasing number of ecologists. Urban avoiders - typically sensitive and specialized bird species often vanish from urbanized landscapes. However, many bird species were able to colonize urban environment and coexist successfully with man. Populations of birds living in such a new type of environment show many characteristics different from populations living in original habitats. The objective of this work is to review current studies about changes of life strategies in urban bird populations such as modifications of acoustic signals, differences in reproductive and food ecology and physiological or behavioural responses.
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Influence of environmental variables on the shape of ultraviolet pattern in Gonepteryx rhamni
Pecháček, Pavel ; Kleisner, Karel (advisor) ; Hořák, David (referee)
Many species are sensitive to a light in ultraviolet spectrum. Some species have surface patterns that reflect ultraviolet light. These markings have been observed in many animal taxa; butterflies (Lepidoptera) are no exception. UV-reflectance in butterflies has been primarily connected to sexual selection and in this respect it has been a subject of many studies. In my work I propose an alternative view to this phenomenon. The aim of my work is to reveal how a particular environmental factors influence the morphospace of UV- reflectant patterns and wing shape of the Gonepteryx rhamni (Pieridae). The effect of various environmental factors (latitude, longitude, altitude, mean annual temperature, mean annual precipitation, normalized difference vegetation index - NDVI or net primary productivity - NPP) on wing morphospace was tested using the methods of Geometric morphometrics. I have also studied shape variability among the males and females, specimens from different locations and differences in morphospace of several G. rhamni subspecies. The dataset used in this analysis includes 118 males and 67 females from the Palearctic ecozone. The effect of almost all environmental (except to NDVI and NPP) predictors on shape of the UV-pattern and wing margin was significant in the case of males. In the...
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Phenotypic plasticity and its role in plant invasions
Hlavička, Matěj ; Herben, Tomáš (advisor) ; Skálová, Hana (referee)
Phenotypic plasticity is the ability of given genotype to produce different phenotypes as a response to environmental cues. Its capability of adaptive response draws an attention of invasion biologists. Although many studies have been performed, the true role of plasticity in an invasion process is still unclear. Comparative experiments suffer from several major constraints - insufficiency in revealing adaptive value of plastic response and uncertain linkage between plasticity and trait value. Further experiments could be focused to reaction norms of fitness instead of trait plasticity. Also, the interspecific interaction of plastic responses is definitely an underestimated mechanism and deserves far more attention than it does today. Possible implications of plant phenotypic plasticity in predicting future invasions require further reaserch.
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Population differentiation of Ochrophytes
Mensová, Anna ; Jurdíková, Katarína (advisor) ; Kulichová, Jana (referee)
This bachelor thesis deals with a differentiation of populations of Ochrophytes (photosynthetic Stramenopiles). Natural populations can differ in many aspects and their differentiation is observed on several levels. Ecophysiological and morphological differences are very often caused by phenotypic plasticity, which is a flexible answer to changing conditions of habitats. Genetic differentiation could express an adaptation to the local environmental conditions. The adaptation and a long-term isolation of populations are considered to be the leading factors in genetic differentiation. The other factors contributing to genetic differentiation are random evolutionary events such as founder effect or genetic drift. Detailed studies of populations lead to uncover the factors that cause the differentiation of populations as well as they contribute to the understanding of speciation mechanisms. The thesis compiled the information about different types of variability among populations within the classes of Ochrophytes.
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