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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Genetická variabilita a fylogeografie mšice zhoubné \kur{Diuraphis noxia} (Aphididae) / Genetic variability and phylogeography of Russian wheat aphid, \kur{Diuraphis noxia} (Aphididae)

SATTRANOVÁ, Anna January 2013 (has links)
Genetic analysis of 433 samples of serious crop pest aphid Diuraphis noxia was conducted with the use of 8 microsatellites loci. Statistical analysis revealed sexual reproduction of D. noxia in temperate regions. The linkage disequilibrium was detected because of the excess of heterozygotes. These results support the theory of RNDr. Starý about the invasion of D. noxia to American continent via states of North Africa, Spain and France.
12

Genetická a morfologická variabilita evropského rodu Cochlodina (Mollusca: Gastropoda: Clausiliidae) se zaměřením na druh C. laminata (Montagu, 1803) / Genetic and Morphological Variability of the European Genus Cochlodina (Mollusca: Gastropoda: Clausiliidae) with Focus on Species C. laminata (Montagu, 1803)

Szalontayová, Veronika January 2013 (has links)
This thesis focuses on the genetical and morphological diversity of plaited door snail (Cochlodina laminata). While small distribution ranges are typical for most species belonging to genus Cochlodina, the distribution range of C. laminata covers most of the European continent, except for its coolest and warmest parts. It has been previously suggested that this species might in fact be a complex of several species and large genetical as well as morphological diversity has been mentioned - however, yet undescribed - in previous studies. Sequences of two mitochondrial genes were used (16S rDNA, COI) and thirteen morphological characteritics have been assessed to investigate this diversity. I discovered that the current concept of C. laminata as a species is not in accordance with the discovered genetical nor morphological variability. The original species C. laminata/C. dubiosa form a common species complex and also interpretation of C. fimbriata will need to be assessed in more detail in the future. Other Central European species are valid species.
13

Systematika a fylogeografie diploidních zástupců druhového komplexu Arabidopsis arenosa / Systematics and phylogeography of diploid lineages of Arabidopsis arenosa complex

Hyklová, Lucie January 2016 (has links)
The Arabidopsis arenosa species complex is closely related to the model species Arabidopsis thaliana. Distribution range of the diploid lineage covers most parts of Central and South-eastern Europe with a remarkable diversity of ecological niches from sea level to alpine peaks. There is still little known about genetic relationships among the diploid populations of A. arenosa. The evolutionary history of the diploid cytotype across its entire range was explored by using 14 nuclear microsatellite loci. Five lineages occupying biogeographically distinct regions were identified in Arabidopsis arenosa complex. These lineages were labelled as Western Carpathians, Eastern Carpathians, Pannonian Lowland, Dinaric Alps and Baltic Shore (according to geographical regions where these lineages occur). Powered by TCPDF (www.tcpdf.org)
14

Fylogeneze a fylogeografie kaprovitých ryb rodu Pelasgus (Teleostei: Cyprinidae) / Phylogeny and phylogeography of the cyprinid fish genus Pelasgus (Teleostei: Cyprinidae)

Viñuela Rodríguez, Nuria January 2016 (has links)
The genus Pelasgus (Cyprinidae) is endemic to the southern part of the Balkan Peninsula and includes seven species. In this work, a multilocus approach has been applied to study phylogenetic relationships between the species and their populations and to revise their distribution areas. 180 specimens from 47 localities from 30 river drainages were analyzed, comprehensively covering the distribution range of the genus. Moreover, samples from type localities of all species were included in the analyses. Mitochondrial (cytochrome b) and nuclear markers (the first intron of ribosomal protein S7, recombination activating gene RAG1 and rhodopsin) were used. Existence of seven well supported lineages was revealed based on cytochrome b, which is the most variable marker. These lineages correspond to P. laconicus, P. marathonicus, P. minutus, P. stymphalicus, P. thesproticus, P. prespensis and Pelasgus sp. The most variable nuclear marker was first intron of S7, which provides almost the same results as cytochrome b, revealing six well supported lineages, whereas RAG1 and rhodopsin appear to be less informative, revealing only four well supported clades. These markers did not separate several species (P. marathonicus, P. stymphalicus, P. thesproticus, and Pelasgus sp.) due to low variability of the markers...
15

Speciace rodu Lethrus (Coleoptera: Geotrupidae) ve východním středomoří / Speciation of the genus Lethrus (Coleoptera: Geotrupidae) of the eastern mediterranean

Drožová, Dana January 2011 (has links)
Earth-boring dung beetles of the genus Lethrus Scopoli, 1777 belong to the family Geotrupidae, classified into three subfamilies (Geotrupinae, Lethrinae a Taurocerastinae). The description of about 120 species, divided into nine subgenera, is based on morphology and geographic distribution. Shape of mandibles, ventral mandible processes, pronotum and structure of external male genitalia are used as diagnostic morphological characters for taxa. The richest species diversity is known from Central Asia. The distribution area reaches, in the east, up to Mongolia and China, and in the west, up to Southeast Europe. All species are robust, relatively large flightless beetles with low dispersial ability. They feed on parts of fresh plants instead of feces like other dung beetles. Master thesis is focused on the species distributed in the Eastern Mediterranean and Central Europe. This area is inhabited only by nominotypical subgenus Lethrus. The main goal of thesis is to clear up phylogenetic relationships between species of subgenus and speciation events using molecular genetic methods. We have examined 91 samples of the genus Lethrus using two mitochondrial genes - cytochrome b (382 bp, 80 sequences), cytochrome oxidase I (815 bp, 87 sequences) and nuclear gene 28S rDNA (D2-D5) (1100 bp, 11 sequences)....
16

Evoluce hostitelské specializace a fylogeografie řasníků čeledi Xenidae (Strepsiptera) / Evolution of host specificity and phylogeography of Strepsiptera parsites of the family Xenidae

Benda, Daniel January 2016 (has links)
The twisted-wing parasites (Strepsiptera) are an endoparasitic order of insects with cosmopolitan distribution, which are sister group of Coleoptera. There are about 600 known species up to date. Strepsiptera parasitize seven insect orders (Thysanura, Orthoptera, Blattodea, Mantodea, Hemiptera, Diptera, Hymenoptera). The family Xenidae is one of the most derived groups of Strepsiptera. Its representatives parasitize aculeate Hymenoptera of three families (Vespidae, Sphecidae, Crabronidae). In comparison to the basal groups, there are well-known hosts for genera of the family Xenidae. Therefore, this group is suitable object for study of the evolution of host specialization. Phylogeny of the family Xenidae was constructed on the basis of molecular analysis of three genes. Moreover, the mapping of ancestral host major groups and biogeographic areas was performed using two methods (parsimony, maximum likelihood). According to the results, the family Xenidae is monophyletic group with Old World origin. There were a several independent switches to the same host groups. This significantly changes the existing ideas about evolution of host specialization and requires a taxonomic revision. Within the family Xenidae, there were several cases of dispersal between the Old World and the New World. Furthermore,...
17

Šíření kudlanky nábožné (Mantis religiosa) v Evropě / Spreading of praying mantis (Mantis religiosa) in Europe

Vitáček, Jakub January 2016 (has links)
Climate change is one of the most important factor determining species ranges. In Europe there is now evidence for northward areal expansion in many Mediterranean insects including the praying mantis (Mantis religiosa). This species is the only representative of the order Mantodea inhabiting central Europe. The northern edge of the species distribution currently reaches latitude 53ř North. Although, the praying mantis is well known insect there is not enough evidence about its phylogeography. In this work three mitochondrial genes (COI, COII, Cyt b) were selected for phylogenetic study. Results indicate three statistically supported distinct lineages in Europe: Eastern European, Central European and Western European. Presumably these lineages are consistent with isolation during the last glacial and re-colonization from glacial refugia. Reduced haplotype diversity on the northern edge suggests currently established populations at the northern distribution border. To validate mtDNA results it was also considered four microsatellite loci. Due to different type of inheritance mtDNA and nuclear DNA it is possible to compare two independent genetic datasets. Microsatellite analysis confirmed results obtained on mitochondrial data. Three major genetic clusters were found: east, west and central. Spatial...
18

Fylogeografie horského okáče Bicyclus anisops v západní Africe / Phylogeography of mountain butterfly ??Bicyclus anisops in West Africa

PETRŮ, Vojtěch January 2014 (has links)
The Gulf of Guinea Highlands is a unique mountane range of volcanic origin, situated on the African mainland in the borther of Nigeria and Cameroon, and the Gulf of Guinea islands of Bioko, S?o Tomé and Príncipe. This area is highly unique as the only large mountains in central and western Africa. The high degree of isolation of these mountains generated high degree of endemism of many groups of organisms; the whole region is thus one of the world biodiversity hotspots (known as the West African Forests). Despite its tremnedous conservation importance, this mountain range is under strong anthropogenic influence, as one of the most densely populated areas in tropical Africa. Despite all these factors, the conservation efforts in West Africa focused mainly on lowland areas of rain forests, whilst only few conservation effort is focused to the mountain habitats. As the other result, the lack of comprehensive biogeographic and phytogeographical studies of mountain flora and fauna is obvious. In this work, I have summarized the results of all crucial studies of the biogeography of the Gulf of Guinea Highlands. I also obtained sequences of three mitochondrial genes (COI, COII, and ND1) of an endemic montane butterfly Bicyclus anisops. Variability in the studied genes was relatively low. Phylogenetic analyses separated haplotypes into 7 well-established groups (1st Mt. Cameroon, 2nd Nkogam I, 3rd Nkogam II, 4th Bakossi-Kupe-Manengouba-Bani, 5th Mbam, 7th Hosséré Enla Fabo 6th all others localities (tj. Bamenda-Banso Mts., Acha Tugi, Mbam, Ngel Nyaki, Gotel Mts.)) but did not significantly resolved relationships among them. Based on the hyplotype diversity of B. anisops as an umbrella species, Mt. Cameroon, Nkogam, Mbam Massif, Mbiame, Hosséré Enla Fabo, Mt. Manengouba, Mt. Kupe and Mt. Oku are considered as localities of the highest conservation importance.
19

Fylogeografie a vnitrodruhová variabilita zlatohlávka Potosia cuprea / Fylogeography and intraspecific variability of the cetoniid beetle Potosia Cuprea

Fuchsová, Aneta January 2012 (has links)
The presented thesis deals with the intraspecific variability of flower beetles species complex Potosia cuprea (Fabricius, 1795), which is a complex of taxa at the species and subspecies level. Flower beetles from species complex Potosia cuprea are among the most variable Palaearctic Cetoniinae at all. Taxa included in the complex produces chromatic range varieties which were, and still are, perceived differently by different authors. Taxa included in the analyses come primarily from western Palaearctic region, with the main emphasis on European species and subspecies. The aim of this work is the use of molecular genetics methods to verify the justification of their species or subspecies level. At all, there were obtained sequences for two mitochondrial genes (cytochrome b and cytochrome oxidase I) from 14 taxa species complex Potosia cuprea and three related species P. angustata (Germar, 1817), P. fieberi (Kraatz, 1931) and P. marginicollis (Ballion, 1870). Molecular analyzes based on COI dataset and concatenate of CytB and COI revealed the existence of a "European" clade P. cuprea, which includes subspecies: Potosia cuprea bourgini (Ruter, 1967), P. c. brancoi (Barraud, 1992), P. c. cuprea (Fabricius, 1775), P. c. metallica (Herbst, 1790) a P. c. obscura (Mikšić, 1954), to which also fit two...
20

Evoluční vztahy mezi druhy parem rodu Barbus (Cyprinidae) s důrazem na Řecko a biogeografie řeckých linií / Evolutionary relationships within genus Barbus (Cyprinidae) with emphasis on Greece, and biogeography of Greek lineages

Kyralová, Eva January 2017 (has links)
Evolutionary relationships between Barbus species have been already studied in the past, but most of the studies were based only on mitochondrial DNA, there is no detailed study based on nuclear markers. This is mainly due to the fact that Barbus species are tetraploid. The western part of Greece has been studied insufficiently, and moreover a greater diversity of freshwater ichthyofauna is expected here. Greece is one of the hotspots of biodiversity. Greek river system is characterized by a significant proportion of endemic species of freshwater fishes. In this work evolutionary relationships between Barbus species were studied, with focus on diversity of Greek lineages. The geographical distribution of Barbus species has been also revised. In total, 192 individuals were analyzed, 156 individuals were from 40 Greek localities and another 36 Barbus species were from other areas of distribution of the genus. Dataset was supplemented with avaible published sequences. For the phylogenetic analysis mitochondrial gene cytochrom b, 1st intron of ribosomal protein gene S7 and 2nd intron of gene beta-actin were used. For both nuclear markers paralog-specific primers were used. The analysis of cytochrom b revealed several well-supported lines: 1. species of southwestern Mediterranean (B. meridionalis and B....

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