Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2006
Forfattere
Remigijus Bakys Rimvis Vasiliauskas Pia Barklund Katarina Ihrmark Jan StenlidSammendrag
No abstract has been registered
Forfattere
Tiina Kuusela Johanna Witzell Annika NordinSammendrag
No abstract has been registered
Forfattere
Jihong Liu Clarke Sonja Klemsdal Erling Fløistad Sissel Haugslien Anne Kathrine Hvoslef-Eide Roar Moe dag-ragnar blystadSammendrag
No abstract has been registered
Forfattere
E. Shutova Frans Emil Wielgolaski S.R. Karlsen O. Makarova N* Berlina T* Filimonova E* Haraldsson Paul Erik Aspholm L. Flø K.A. HøgdaSammendrag
No abstract has been registered
Forfattere
Halvor Solheim Nenad Djuro KečaSammendrag
Twenty-five tree species were recorded as hosts for five European Armillaria species in studies on forest ecosystems in Serbia. Armillaria was most frequently isolated from the conifers Picea abies and Abies alba and from the deciduous trees Fagus moesiaca and Quercus petraea. A. mellea and A. gallica coexisted in hardwood forests in northern and central parts of Serbia, while A. ostoyae and A. cepistipes were mostly present in coniferous forests in the southern mountain region of Serbia. The distribution depended on the Armillaria species, altitude, and the forest type.
Forfattere
Roar Moe Erling Fløistad dag-ragnar blystadSammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Forfattere
Filip Moldan O. Janne Kjønaas Arne Olav Stuanes Richard Frederic WrightSammendrag
Beginning in 1991, we have added nitrogen (N) to the 0.5-ha, N-poor, coniferous-forested catchment G2 NITREX at Gårdsjön, Sweden, to investigate the consequences of chronic elevated N deposition. We have added 40 kg N ha−1 yr−1 in fortnightly doses of NH4NO3 to the ambient 15 kg N ha−1 yr−1 by means of a sprinkling system. NO3 concentrations in runoff increased during 13 years from < 1 to 70 μeq L−1, and in 2004 comprised about 10% of N input. Inhibition of NO3 immobilisation due to increased availability of NH4 might explain the increased leaching of NO3. C and N pools in the forest floor increased but C/N ratio has not changed. The increase in NO3 leaching thus occurred independently of change in C/N ratio. The results from Gårdsjön demonstrate that increased leaching of inorganic N and decrease in C/N ratio respond to increased N deposition at greatly different time scales. NO3 concentrations increased in runoff although the C/N ratio of forest floor has not changed.
Forfattere
Paal KrokeneSammendrag
Bark beetles and associated phytopathogenic fungi elicit defence responses in conifers that may interfere with beetle establishment and development. Norway spruce is serving as a useful model species for studies of induced defences elicited by beetle attacks, fungal inoculation, and treatment with chemical elicitors.When trees are pretreated with a sublethal dose of fungal inoculations or with the phytohormone methyl jasmonate they become much more resistant to subsequent bark beetle attacks or artificial mass inoculations with fungi. This induced disease resistance follows dose-response dynamics, is nonspecific with respect to the pretreatment organism, appears to be nonsystemic, takes weeks rather than days to become activated, and can also be activated by mechanical wounding alone.Application of methyl jasmonate to Norway spruce stems induces a massive increase in terpene levels and external resin flow on the stem, whereas no increase is observed in soluble phenolics. Methyl jasmonate-application also leads to significantly less bark beetle colonization, with shorter parental galleries and fewer eggs laid in treated bark. There were also reductions in the number of beetles produced and the mean dry weight per beetle in methyl jasmonate-treated bark. Furthermore, fewer beetles were attracted to conspecifics tunneling in MJ-treated bark.The exact mechanisms responsible for induced resistance in Norway spruce and other conifers have not been determined, but inducible anatomical defense responses such as changes in polyphenol-containing parenchyma cells (PP cells) in the phloem and induction of traumatic resin duct formation in the sapwood seem to play an important role.