Sökning: "hylobius"

Visar resultat 6 - 10 av 15 avhandlingar innehållade ordet hylobius.

  1. 6. Chemical defence in Norway spruce

    Författare :Marie Danielsson; Anna-Karin Borg-Karlson; Anders Backlund; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; volatiles; terpenes; green leaf volatiles; stilbenes; stress response; nepetalactone; Picea abies; Hylobius abietis; Cinara pilicornis; Oligonychus ununguis; Heterobasidion annosum; Chemistry; Kemi;

    Sammanfattning : Norway spruce (Picea abies) responds to stress by biosynthesis of chemical substances, which can deter invading insects or pathogens. Some of these substances are volatile and can be emitted to the surroundings while others are accumulated within the tree. LÄS MER

  3. 7. Stress Related Emissions of Norway Spruce Plants

    Författare :Marie Pettersson; Anna-Karin Borg-Karlson; Torkel Berglund; Åsa Emmer; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; volatiles; terpenes; green leaf volatiles; stress response; nepetalactone; SPME; Picea abies; Hylobius abietis; Cinara pillicornis; Chemistry; Kemi;

    Sammanfattning : The interactions between plants and insects are mediated by volatile molecules. Plants respond to stress by biosynthesis of chemical substances which can deter invading insects or pathogens. Some of these substances are volatile and are emitted to the surroundings and may attract or repel insects. LÄS MER

  4. 8. Volatiles of Conifer Seedlings : Compositions and Resistance Markers

    Författare :Astrid Kännaste; Anna-Karin Borg-Karlson; Anders Backlund; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Conifers; Norway spruce; Scots pine; Nalepella; Oligonychus ununguis; green leaf volatiles; terpenes; aromatics; benzenoids; SPME; induced defense reaction; Organic chemistry; Organisk kemi;

    Sammanfattning : Pine weevils cause major damage to newly planted conifer seedlings in reforestation areas. However, recent findings indicate that small (“mini”) seedlings, planted at the age of 7-10 weeks, are gnawed less by pine weevils than the larger, conventionally planted seedlings. LÄS MER

  5. 9. Secondary plant metabolites as defence against herbivores and oxidative stress : Synthesis, isolation and biological evaluation

    Författare :Katharina Bratt; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : In this thesis the isolation, synthesis and biological evaluation of natural defense compounds against herbivores or oxidative stress is discussed.The first part concerns the metabolites of platyphylloside ((5S)-5-hydroxy-1,7-bis-(4-hydroxyphenyl)-3-heptanone-5-O-β-D-glucopyranoside), a phenolic glucoside found in birch (Betula pendula) that possess digestibility inhibiting activity in herbivores. LÄS MER

  7. 10. Enhancing spruce defence against an insect pest : effects of somatic embryogenesis and methyl jasmonate treatment

    Författare :Kristina Berggren Nieto; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Enhancing plant resistance against pests has the potential to become a sustainable alternative within forestry. Exogenous application of the plant defence signalling hormone methyl jasmonate (MeJA) as well as propagation through somatic embryogenesis (SE) has been shown to increase Norway spruce (Picea abies) plant’s resistance to the major forest regeneration pest the pine weevil Hylobius abietis. LÄS MER