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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.
1

Identity and limits of Limbella tricostata (Musci: Amblystegiaceae)

Christy, John A. January 1985 (has links)
Investigation of morphology, karyotype, isozymes, cultivation, geography and habitat confirmed differences between Limbella tricostata (Sull.) CM. and Sciaromium fryei Williams. Significant differences were observed experimentally in branch bud frequency, leaf insertion angle, leaf areolation, chromosome length, mobility of superoxide dismutase and shoot orientation. Sciaromium fryei is considered a subspecies of Limbella tricostata. Chromosome numbers of both subspecies is n=11. L. tricostata ssp. tricostata has a Bryum type sporeling and a hypnaceous peristome, and is thought to have derived from L. pachyloma (Mont.) C.M. or its antecedent after long-distance dispersal from South America to Hawaii no later than the mid-Tertiary. L. tricostata ssp. fryei is thought to have derived from L. tricostata ssp. tricostata after long-distance dispersal from Hawaii to North America in the mid- to late Tertiary. / Science, Faculty of / Botany, Department of / Graduate
2

A study of the Brachythecium asperrimum-frigidum species complex

Hoisington, Barbara Ludlow January 1979 (has links)
This thesis describes a study of six North American, dioicous Brachytheeium species possessing a rough seta. The phenetic variability of the six species was analysed in order to clarify the relationships, between species and to provide .simpler, more reliable means of identifying specimens. As a consequence of this investigation, the taxonomic identities of B. asperrimum (Mitt. ex. C. Muell.) Sull. and B. frigidum (C. Muell.) Besch, have been established through numerical analyses of the variation in the gametophytic features of the two species. Two types of analyses were used: a principal components analysis and a cluster analysis. The phenetic variation and habitat specificity of each species were analysed and documented and synonymy and ranges presented. A. test of the features considered diagnostic for the two species has been performed and the results of this test used to devise a reliable key. The relationships of the two species to the other North American dioicous species possessing rough setae were determined using a principal components analysis and. a cluster analysis. B. asperrimum (Mitt. ex. C. Muell.). Sull is shown to be closely related to B. bolanderi (Lesq.) Jaeg. and Sauerb.. B. frigidum (C. Muell.) Besch. is shown to be closely related to B. rivulare B.S.G. and B. nelsonii Grout. A dendrogram and discussion of the hypothetical, cladistic relationships of the six species are provided. / Science, Faculty of / Botany, Department of / Graduate
3

Functional characterization of hexokinases in the moss Physcomitrella patens /

Olsson, Tina, January 2005 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 3 uppsatser.
4

Ecological study of the moss \kur{Hamatocaulis vernicosus} / Ecological study of the moss \kur{Hamatocaulis vernicosus}

ŠTECHOVÁ, Táňa January 2012 (has links)
The thesis is focused on the endangered wetland moss Hamatocaulis vernicosus. The studies included vegetation and chemical characteristics of the species? habitats and long-term reaction to management and other environmental factors, comparison of ecological requirements of H. vernicosus and two related species, differences of habitat preferences among some European regions (Bohemian Massif, Western Carpathians, Southern Europe) and among parts of the Czech Republic. Recent and historical distribution of the species was compared, including the quantification of all recent populations.
5

Esporos de espécies selecionadas de musgos (Bryophyta) de Minas Gerais: morfologia, ultraestrutura e aspectos ecológicos

Rodrigues, Raquel Saar 21 February 2014 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-07-04T10:44:48Z No. of bitstreams: 1 raquelsaarrodrigues.pdf: 1388727 bytes, checksum: 2d848a6f30cf75ad6633c4cecf0c916f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-08T13:09:32Z (GMT) No. of bitstreams: 1 raquelsaarrodrigues.pdf: 1388727 bytes, checksum: 2d848a6f30cf75ad6633c4cecf0c916f (MD5) / Made available in DSpace on 2017-08-08T13:09:32Z (GMT). No. of bitstreams: 1 raquelsaarrodrigues.pdf: 1388727 bytes, checksum: 2d848a6f30cf75ad6633c4cecf0c916f (MD5) Previous issue date: 2014-02-21 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os musgos, incluídos na divisão Bryophyta, são caracterizados pela criptogamia, ausência de vasos condutores e presença de gametófitos folhosos (fase de vida dominante), com filídios organizados espiraladamente. O padrão de ramificação do gametófito, em conjunto com a sua forma de crescimento, é chamado de forma de vida que, nos musgos, pode ser tapete, trama, dendróide, pendente, relva e almofada. O esporófito é formado por pé, seta e cápsula, sendo esta última, o local de produção dos esporos, unidades de dispersão das espécies, que apresentam parede celular formada por perina, exina e intina. Estudos em Palinologia de musgos, já elucidaram questões importantes acerca da esporogênese, germinação e morfologia dos esporos de muitas espécies, sendo alguns deles empregados em taxonomia. No entanto, dados que correlacionam características morfológicas dos esporos com as estratégias adaptativas das espécies ainda são raros. Sendo assim, o objetivo do presente trabalho foi realizar o estudo palinológico de 19 espécies selecionadas de musgos que ocorrem no estado de Minas Gerais, e relacionar os dados palinológicos obtidos, com as estratégias adaptativas das espécies estudadas. Foram incluídas no conjunto amostral espécies acrocárpicas e pleurocárpicas, que ocorrem em diferentes substratos, e com formas de vida variadas. Para o estudo palinológico das espécies, os esporos foram observados sob microscópio de luz antes e após acetólise, momento em que foram realizadas as medidas padrão para estudos palinológicos, e microscópio eletrônico de varredura. Após as análises palinológicas e obtenção dos dados acerca das características adaptativas das espécies, as informações foram incluídas em uma matriz binária e, empregando-se o software PAST 15.2, foi realizada a análise de agrupamento (cluster) para verificar como as espécies se agrupam em função das características estudadas. Os resultados palinológicos demonstram a existência de três padrões distintos de ornamentação da perina: granulada formada por grânulos simples, granulada formada por grânulos compostos e baculada. A ornamentação observada nos esporos de Weissia controversa foi descrita pela primeira vez. A espécie Leptodontium viticulosoides apresentou esporos anisomórficos. As análises de agrupamento revelam uma relação entre espécies acrocárpicas, a ocupação do substrato cimento e a presença de uma parede espessa no esporoderma. / Mosses are cryptogamic land plants, included in Bryophyta and characterized by an avascular condition and the presence of leafy gametophytes (dominant life generation), with leaves spirally arranged around the stem. The growth form, together with the branching pattern, is called the life-form, which may be mat, weft, dendroid, pendant, turf and cushion. The sporophyte consists of foot, seta and capsule. The spores, dispersal units of mosses, are formed in the capsule and show a three layered sporoderm, consisting in perine, exine and intine. Studies in palynology of mosses have elucidated important issues about sporogenesis, spore germination and morphology of many species, some of them being employed in taxonomy. Observing that the data correlating morphological characteristics of the spores with the adaptive strategies of species are still rare, this work aimed to study the spores of 19 species of mosses which occur in the state of Minas Gerais and to correlate the palynological data obtained with the adaptive life strategies of species. We included in the sample a set of acrocarpous and pleurocarpous mosses which occur on different substrates and show with different life-forms. For the palynological study, the spores were observed untreated or submitted to the acetolysis method, under light microscope and scanning electron microscope. After we obtained the data concerning to the palynological analysis and the adaptative strategies of species, the information was included in a binary matrix and through the PAST 15.2 software, a cluster analysis was performed. The palynological results show three distinct patterns of perine ornamentation: granular formed by individual granules, granular formed by compounded granules and baculated. The ornamentation observed in spores of Weissia controversa was first described. Leptodontium viticulosoides showed anisomorphic spores. Cluster analysis revealed a relationship between acrocarpous species, the occupation of the substrate concrete and the presence of a thick wall in sporoderm.
6

Botanická ilustrace - mechorosty / Botanical Illustration - Bryophytes

Kolářová, Martina January 2013 (has links)
This diploma thesis deals with Bryophyta studies as a part of curriculum at primary schools as well as at lower and upper grammar schools. It determines the field of studies and the expected outcomes in the Human and Nature subject matter, it searches for the link between bryophyta and cross-sectional topics. The relation of pupil's key competences to bryophyta is being reflected, too. It compares the subject range of Bryophyta in school books. Furthermore, the thesis sums up the history of botanical illustration in the world as well as in our country, it inquires into basic rules of botanical illustration and line drawing techniques. The contemporary field guides are completed by the means of the research of students' books, popular and specialist literature and internet portals. Based on the theoretical part, this diploma thesis determines the teaching methodology of bryophyta drawing. The list of bryophyta, which are suitable for line drawings and usable as a teaching aid, is based on the practical part of this diploma thesis. 43 author's drawings with uniform measuring scale are attached.
7

Bryophytes on boulders : diversity, habitat preferences and conservation aspects /

Weibull, Henrik, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
8

Bryophytes, lichens and dead wood in young managed boreal forests /

Rudolphi, Jörgen, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
9

SHI/STY-family members redundantly regulate auxin homeostasis in basal and higher plants /

Eklund, Magnus, January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 4 uppsatser.
10

Taxonomy and Phylogeny of the Liverwort Genus Thysananthus (Marchantiophyta; Lejeuneaceae) / Taxonomie und Phylogenie der Lebermoosgattung Thysananthus (Marchantiophyta; Lejeuneaceae)

Sukkharak, Phiangphak 08 June 2011 (has links)
No description available.

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