Sökning: "abiotic factors"

Visar resultat 1 - 5 av 113 avhandlingar innehållade orden abiotic factors.

  1. 1. Acclimation of plants to combinations of abiotic factors : connecting the lab to the field

    Författare :Zsofia Réka Stangl; Vaughan Hurry; Lisa Ainsworth; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nitrogen; carbon dioxide; temperature; thermal acclimation; mycorrhiza; boreal forest; climate change; C:N balance; allocation; respiration; photosynthesis; terrestrial biosphere model;

    Sammanfattning : Increasing atmospheric CO2 and other greenhouse gasses coupled to the accelerated rate of global warming puts plants and ecosystems under the strain of a rapidly changing abiotic environment. Understanding the impacts of changing global climate is a strong focus of plant science and the establishment of more resilient crop variants is an important goal for breeding programs. LÄS MER

  2. 2. Untangling ambiguities in the microbial fossil record : experimental abiotic and biological approaches

    Författare :Sigrid Huld; Anna Neubeck; Sebastian Willman; Sean McMahon; Barbara Cavalazzi; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; chemical gardens; pseudofossils; experimental mineralisation; microbial fossils; methanogens;

    Sammanfattning : Life on early earth has long been the topic of discussion for many researchers: how did it come to be? Which cells came first? Where can we find them? The most ancient rocks on our planet may hold some of the answers to these questions, but many may only be answered in laboratories. Chemical and morphological traces can be found from Archaean deposits, tantalisingly similar to modern day prokaryotes. LÄS MER

  3. 3. Systemic fungal diseases in natural plant populations

    Författare :Anders Wennström; Lars Ericson; Peter G. Ayres; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systemic diseases; rust; smut; Puccinia minussensis; Lactuca sibirica; Puccinia pulsatillae; Pulsatilla pratensis; lateral growth; abiotic factors; disease transmission; Svampsjukdomar hos växter;

    Sammanfattning : The purpose of this thesis was to study interactions between systemic fungal diseases and perennial plants. Using the systemic rust Puccinia minussensis on the host plant Lactuca sibirica, and the rust Puccinia pulsatillae on the host plant Pulsatilla pratensis, this thesis focused on: (i) the effects of systemic diseases on their hosts (ii) host and pathogen responses to abiotic factors, (iii) the importance of life history strategies for understanding host-pathogen interactions, and (iv) the evolutionary consequences of living in close associations. LÄS MER

  4. 4. Abiotic Stress Tolerance. Metabolic and Physiological Effects of Compatible Solutes and Calmodulin on E. coli and Tobacco

    Författare :Jenny Lindberg; Tillämpad biokemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Abiotic stress; compatible solutes; osmotic stress; osmoprotectants; trehalose; calmodulin; E. coli; N. tabacum; genetic engineering; Biotechnology; Bioteknik; Biochemistry; Metabolism; Biokemi; metabolism; glycine betaine;

    Sammanfattning : In their natural habitats, bacteria and plants can be exposed to abiotic stresses such as drought, high salt concentrations and freezing, which are factors limiting their capacity for growth and proliferation. To withstand environmental stresses, they have evolved specific stress responses. LÄS MER

  5. 5. Mechanisms and genes controlling the signalling network for biotic and abiotic stress defences in Arabidopsis thaliana (L.) Heyhn : Functional cross-talk between photo-produced reactive oxygen species, photosynthesis and plant disease defence responses

    Författare :Christine Chi-Chen Chang; Stanislaw Karpinski; Christine Foyer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; reactive oxygen species; Arabidopsis thaliana; signalling work; biotic stress; abiotic stress; Plant physiology; Växtfysiologi;

    Sammanfattning : Excess excitation energy, mechanical injury and defence against pathogens, each trigger rapid production of reactive oxygen species (ROS) in Arabidopsis thaliana leaves. ROS, such as hydrogen peroxide (H2O2), are required for the induction of systemic acquired acclimation and may lead to redox changes in photosynthetic electron transport (PET). LÄS MER