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.
2008
Forfattere
Carl Gunnar Fossdal Ari M. Hietala Igor A. Yakovlev Halvor SolheimSammendrag
The root-rot causing fungus Heterobasidion annosum sensu lato is the most devastating pathogen of conifers in Europe. This pathogen enters Norway spruce through the roots and can colonize the tree from within, growing as a saprophyte when established within the dead heartwood and acting as a necrotroph when in contact with living host tissue. Despite the high incidence of damage, trees have defences against this pathogen in the bark and living wood. Furthermore, spruce has a defense against internal attack by forming a reaction zone, in this case the host defense is directed inwardly by the still living sapwood toward the central colonized heartwood. We have studied the host responses to infection in Norway spruce clones at the transcriptional level and found that the speed of recognition and that spatial defense signalling appears to be the hallmarks of trees with high degree of resistance...
Forfattere
Peder GjerdrumSammendrag
No abstract has been registered
Sammendrag
The area of wood protection is in a period of change. New wood protection systems have been developed while their mode of action remains insufficiently understood. The development of molecular methods provides potential tools to investigate the interaction between modified wood and decay fungi. One small step to tackle some of the unsolved questions about the mode of action of modified wood is taken in this study. A specific and quantitative real-time PCR (QRT-PCR) assay was now established for identifying and quantifying early stages of fungal colonisation in modified wood and for profiling growth dynamics of the white-rot fungus Trametes versicolor through different stages of decay. QRT-PCR of colonisation of three different wood modification systems (acetylation, furfurylation, thermal modification), two reference treatments (Cu-HDO, CCA) and Scots pine sapwood as control was performed. Incubation time was 2, 4, 6, 8 and 10 weeks...
Forfattere
Yijie WuSammendrag
Luftforurensninger og klimaendringer påvirker kjemien i kronedrypp og jordvann i boreale skoger. Løst organisk materiale (DOM), inklusiv løst organisk karbon (DOC) og løst organisk nitrogen (DON), spiller en nøkkelrolle, og det er derfor nødvendig å forstå hvordan DOM blir påvirket, ikke bare av luftforurensninger og klimatiske faktorer, men også av andre faktorer. Denne avhandling undersøker faktorer som påvirker DOC og DON i norske skogøkosystem, med bruk av data fra de norske ICP Forests Level II-flater og andre studier...
Sammendrag
No abstract has been registered
Forfattere
Wim de Vries Svein Solberg Matthias Dobbertin Hubert Sterba Daniel Laubhann Gert Jan Reinds Gert-Jan Nabuurs Per Gundersen Mark A. SuttonSammendrag
Nitrogennedfallet i skog virker gjødslende på skog, og fører derfor til økt karbonbinding. Så selv om nitrogennedfallet er en forurensning, så har det den positive effekt at det bidrar til å motvirke klimaendringene. Spørsmålet er hvor stor denne effekten er. Vi har i vårt EU/Forest Focus-prosjekt ”Assessment of the relative importance of nitrogen deposition, climate change and forest management on the sequestration of carbon at intensive monitoring plots in Europe” estimert denne effekten til å være omkring 30 kg ekstra bundet karbon for hver kg nitrogen som blir avsatt i skog...
Sammendrag
The Norwegian records of the ant Camponotus vagus (Scopoli, 1763) are presented and the distribution is discussed. Information on its biology and habitat choice is given. C. vagus is an overlooked species that must be considered rare in Norway
Sammendrag
No abstract has been registered
Forfattere
Harald Kvaalen Øystein JohnsenSammendrag
It has been shown previously that height growth and bud phenology are influenced by the temperature during zygotic embryogenesis in Picea abies.To test whether this phenomenon operates within individual plants, clones produced through somatic embryogenesis were used. Seeds were from a full-sib family produced in both a cold (outdoor) and a warm (inside a glasshouse) environment. Embryogenic clones derived from mature zygotic embryos from both crossing environments were cultured at 18, 23 and 28 during the proliferation and embryo maturation steps.After the second growing season in a glasshouse, plants from the warm seed production environment were taller and had significantly later bud set. For the first time, it is also shown that plants are influenced by the in vitro temperature during somatic embryo development. The warmer the temperature, the later the plants formed terminal buds. The differences were similar to those produced by a provenance separation of 4-6 degrees of latitude.The results indicate that there exists a mechanism in P. abies that operates during embryo development and adjusts the timing of bud set in accordance with the temperature conditions in which the mother tree lives. This in turn counteracts negative effects of gene flow among populations located along altitudinal and latitudinal gradients.
Forfattere
Nadeem Yaqoob Carl Gunnar Fossdal Bao Dzung Diep Halvor SolheimSammendrag
Due to the great economic losses caused by the root and butt-rot pathogen Heterobasidion annosum, developments of efficient control measures are warranted. H. annosum a necrotroph colonize the Norway spruce from inside and is responsible of 10-13 millions Euros losses in Norway alone. Considerable clonal variation has been recorded for Norway spruce in resistance towards H. annosum, but the defence mechanisms contributing to host resistance remain poorly understood. The recent genome sequencing of Populus has made the genus a model to facilitate tree genetics. Genome-wide transcript profiling of Populus tremula upon pathogen attack will now be used, and homologues of Norway spruce genes to defence genes up-regulated in Populus will be identified. Populus-Phellinus tremula pathosystem is selected as P. tremula behaves like H. annosum.
