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21	Chemical defence in Norway spruce Danielsson, Marie January 2011 (has links) 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. Information about the susceptibility of individual plants to infestation, their volatile emissions and chemical defence is of interest, for example, in selecting plants for tree breeding programs. The first part of this research focused on volatiles emitted by Norway spruce plants. Collection of headspace volatiles by SPME and subsequent separation and identification with GC-MS was used to investigate Norway spruce plants of different ages and stress conditions as well as trapping semiochemicals like nepetalactone emitted by the spruce shoot aphids. It was even possible to analyse the emission of single needles in vivo and obtain spatial localisation of the stress reaction to methyl jasmonate or spruce spinning mites. Seedlings of different ages showed differences in chemical composition of emitted volatiles, with the pine weevil repellent, (4S)-(-)-limonene, one of the main compounds. Wounded phloem of conventional plants emitted high amounts of monoterpenes while the phloem of mini plants emitted (3Z)-hexenal and (3Z)-hexen-1-ol. In addition, a method to separate and identify the four diastereomers of nepetalactone by GC-MS and characteristic m/z-fragments was accomplished. The second part of the research deals with the chemical response of Norway spruce roots to inoculation with Heterobasidion annosum. Terpene concentrations increased after inoculation or wounding but the composition was mainly associated with clone identity and not to susceptibility or treatment. In contrast, inoculation with H. annosum induced a treatment-specific alteration of phenol composition. The constitutive phenol composition differed between more and less susceptible clones. The phenols astringin and astringin dimers (piceasides) as well as the terpene α-longipinene may be suitable markers of low susceptibility for P. abies to Heterobasidion. / QC 20110314 volatiles terpenes green leaf volatiles stilbenes stress response nepetalactone Picea abies Hylobius abietis Cinara pilicornis Oligonychus ununguis Heterobasidion annosum Chemistry Kemi
22	Šakninės pinties paplitimas Nemenčinės miškų urėdijos Meros ir Magūnų girininkijų pušynuose / Distribution of Heterobasidion annosum in Scots pine plantations of Mera and Magūnai forest districts Navalinskas, Darius 06 June 2005 (has links) The distribution of Heterobasidion annosum in Scots pine stands in Nemenčinė Forest Enterprise, Mera and Magūnai forest districts were examined in this Master thesis. The object of the study: Scots pine stands that were established on formerly used agricultural land, former tank range areas and the stands growing in the cut areas of mature stands. Also, the Scots pine stands where after partly clear sanitation cuttings the birch groups were planted, in purpose to avoid the disturbances of Heterobasidion annosum. The aim of the study: to summaries the information about the distribution of Heterobasidion annosum in Lithuanian forests; to study the distribution of Heterobasidion annosum in Scots pine plantations established in agricultural lands and the cut areas of mature stands. The evaluation of the effectiveness of earlier used partly clear sanitation cuttings against Heterobasidion annosum in disturbed stands was also done. Methods: the distribution of Heterobasidion annosum in the forests of Nemenčinė Forest Enterprise, Mera forest district was evaluated visually. Each studied plot was evaluated according 4 grades. 6 assessment plots in Magūnai forest district were evaluated for the effectiveness of partly clear sanitation cuttings. The stand characteristics of the remained healthy pine and birch trees were measured using standard silvicultural mensuration methods, taking the measurements of each tree at breast height, in 2 cm precision. The results: The distribution of... [to full text] Forestry Brandžių medynų kirtavietės Šakninė pintis Scots pine plantations Žemės ūkio naudmenos Mature stands Cut areas Pušynai Agricultural lands Heterobasidion annosum
23	Transcript profiling of the Heterobasidion-conifer pathosystem : host and pathogen responses to biotic stress / Adomas, Aleksandra, January 2007 (has links) (PDF) Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 5 uppsatser.
24	Actions of lignocellulolytic enzymes on Abies grandis(grand fir) wood for application in biofuel production Cherdchim, Banyat 27 October 2010 (has links) No description available. 000 Allgemeines Wissenschaft Forest Sciences and Forest Ecology Abies grandis Armillaria mellea Heterobasidion annosum Heterobasidion parviporum Pleurotus ostreatus Trametes versicolor Coniophora puteana biodegradation cell wall modification urea formaldehyde ammonium sulphate mass loss area fraction stained cell wall cell wall area latewood earlywood oxidative enzyme MBTH laccase-mediator manganese peroxidase butylhydroxytoluol carbon chromatography fraction Coprinopsis cinerea decay fungi 1 4-dihydroxybenzene p-benzochinone 3 5-di-tertbut-4-hydroxy-toluene GC-MS analysis gel electrophoresis growth inhibition 4-hydroxy cinnamic acid laccase induction nitrogen phenolic compounds p-coumaric acid wood extraction wood extractives biofuels chemical pretreatment physico-chemical pretreatment biological pretreatment microwave irradiation liquid acid rate of production of glucose kinetic curve of production of glucose influence of wood extractive influence of phenolic compound Abies grandis Armillaria mellea Heterobasidion annosum Heterobasidion parviporum Pleurotus ostreatus Trametes versicolor Coniophora puteana biodegradation cell wall modification urea formaldehyde ammonium sulphate mass loss area fraction stained cell wall cell wall area latewood earlywood oxidative enzyme MBTH laccase-mediator manganese peroxidase butylhydroxytoluol carbon chromatography fraction Coprinopsis cinerea decay fungi 1 4-dihydroxybenzene p-benzochinone 3 5-di-tertbut-4-hydroxy-toluene GC-MS analysis gel electrophoresis growth inhibition 4-hydroxy cinnamic acid laccase induction nitrogen phenolic compounds p-coumaric acid wood extraction wood extractives biofuels chemical pretreatment physico-chemical pretreatment biological pretreatment microwave irradiation liquid acid rate of production of glucose kinetic curve of production of glucose influence of wood extractive influence of phenolic compound 48.46 Holz YQ 000: Forstbotanik

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