Sökning: "pheromones"

Visar resultat 6 - 10 av 50 avhandlingar innehållade ordet pheromones.

  1. 6. Ecology and evolution in a host-parasitoid system : Host search, immune responses and parasitoid virulence

    Författare :Lisa Fors; Peter Hambäck; Wertheim Bregje; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Host-parasitoid interactions; Plant-herbivore interactions; Host search; Volatiles; Pheromones; Geographic variation; Cellular defence; Melanisation; Encapsulation; Asecodes; Galerucella; Plant Ecology; växtekologi;

    Sammanfattning : In host-parasitoid systems, there is a continuous coevolutionary arms race where each species imposes a strong selection pressure on the other. The host needs to develop defence strategies in order to escape parasitism and the parasitoid must evolve counter-defence strategies in order to overcome the host’s immune defence and successfully reproduce. LÄS MER

  3. 7. Natural products from nonracemie building blocks : synthesis of pine sawfly pheromones

    Författare :Michael Larsson; Torbjörn Norin; Gunnar Westman; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; Total synthesis; diastereoselective addition; dimethylzinc; Lewis acid; alkyllithium; Organisk kemi; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis describes a number of synthetic approaches for obtaining chiral, enantiomerically pure natural products, in particular some semiochemicals. This has been accomplished by using various strategies; by starting from compounds from the chiral pool, by using chiral auxiliaries, via enzymatic resolutions or by chemical asymmetric synthesis. LÄS MER

  4. 8. Identification and Syntheses of Semiochemicals Affecting Mnesampela privata and Trioza apicalis

    Författare :Anna Nilsson; Erik Hedenström; Anna-Karin Borg-Karlsson; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mnesampela privata; semiochemicals; pheromones; kairomones; 3Z; 6Z; 9Z -3; 6; 9-nonadecatriene; 3Z; 6Z; 9Z -3; 6; 9-heneicosatriene; carrot psyllid; Trioza apicalis; Organic chemistry; Organisk kemi;

    Sammanfattning : The Autumn gum moth, Mnesampela privata (Lepidoptera: Geometridae) is an endemic Australian moth whose larvae feed upon species of Eucalyptus. The moths favorite host plants are E. globulus and E. nitens which are the most important species used in commercial plantations of the Australian pulpwood industry. LÄS MER

  5. 9. Sex pheromone biosynthesis in moth pests : From gene discovery to biotechnological production

    Författare :Marie Dam; Feromongruppen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lepidoptera; Moths; Sex pheromones; Biosynthesis; Desaturases; Gene characterisation; Transcriptomics; Heterologous expression; Biotechnology; integrated pest management;

    Sammanfattning : Moths (Lepidoptera) are some of the most economically important pests in human agriculture. Conventional insecticides used for management promote insecticide resistance in addition to cause human- and environmental harm. This emphasises an inescapable need for sustainable alternatives and integrated practices. LÄS MER

  7. 10. Plants as Factories for Insect Pheromone Production : Deciphering and Reconstructing Sex Pheromone Biosynthetic Pathways of Female Moths

    Författare :Yihan Xia; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pheromones biosynthesis; desaturases; elongases; reductases; plant factories;

    Sammanfattning : Compared to other organisms in which the fatty acyl desaturases (FADs) are mostly involved in normal cellular lipid metabolism, moth FADs have evolved extent functions in the biosynthesis of sex pheromones. Female moths releasespecies-specific sex pheromones to attract conspecific males over a long distance for mating. LÄS MER