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.
2011
Sammendrag
The northernmost range of beech (Fagus sylvatica L.) is in southern Norway and consists of two distinct and isolated distributions, a single population at Seim in West Norway and several adjacent populations in Vestfold, East Norway. The modest beech pollen deposits beyond these main distributions suggest that the Norwegian beech distribution has never been an extension of the south Scandinavian range. We used genetic markers and historical sources to trace the ancestor populations for the beech at Seim and Vestfold, hypothesising Denmark as the most likely source. Nuclear inter-simple sequence repeat markers, amplified by polymerase chain reaction (PCR), were applied to estimate genetic distances between beech populations in Norway, England and Denmark. The variation in chloroplast DNA polymorphism was estimated using PCR-restriction fragment length polymorphism. The nuclear genetic data indicate Denmark as a source for the beech in Norway, although the data are less certain in the case of Seim than in that of Vestfold. The populations from South England were genetically different from most Scandinavian populations. The genetic variation within Norwegian populations was only slightly lower than that of the English and Danish populations, questioning birds as vectors for dispersal. Thus, the pollen data and our results are in accordance with the intentional introduction and documented human migrations across Skagerrak before and during the Viking Age.
Forfattere
Daniel Kwaku Addo Asante Igor A. Yakovlev Carl Gunnar Fossdal Anna Marie Holefors Lars Morten Opseth Jorunn E. Olsen Olavi Junttila Øystein JohnsenSammendrag
No abstract has been registered
Forfattere
Igor A. Yakovlev YeonKyeong Lee Bjørn Rotter Tore Skrøppa Øystein Johnsen Jorunn Elisabeth Olsen Carl Gunnar FossdalSammendrag
No abstract has been registered
Forfattere
Carl Gunnar Fossdal Nadeem Yaqoob Halvor Solheim Jan Karlsson Benedicte Rieber AlbrectsenSammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Sammendrag
Experimental evidence shows that Norway spruce can adjust adaptive traits by a kind of long-term memory of temperature and day length present at the time of its early seed development. This mechanism is termed epigenetics; changes in gene activity not based on differences in the genetic code and yet transferable from one generation to the next. This is a rapidly growing research field in human, animal and plant genetics.
2010
Forfattere
Arild Andersen Trond Hofsvang May Bente Brurberg Christer Magnusson Trond Rafoss Brita Toppe Anne Marte Tronsmo Bjørn Økland Leif SundheimSammendrag
No abstract has been registered
Forfattere
Arild Andersen Trond Hofsvang May Bente Brurberg Christer Magnusson Trond Rafoss Brita Toppe Anne Marte Tronsmo Bjørn Økland Leif SundheimSammendrag
No abstract has been registered
Forfattere
Arild Andersen Trond Hofsvang May Bente Brurberg Christer Magnusson Trond Rafoss Anne Marte Tronsmo Bjørn Økland Leif SundheimSammendrag
No abstract has been registered
Sammendrag
Today the spruce bark beetle Ips typographus is always univoltine in Northern Europe including Norway and completes development from egg to adult between May and August. Further south in Europe, development is bivoltine with the completion of two generations in most years. A temperature-driven developmental model suggests that by 2070-2100 the voltinism of I. typographus will change dramatically in Norway. If summers become only 2.5°C warmer than today bivoltinism can be expected every single year in the major spruce growing areas in S-Norway. This is likely to have dramatic effects on forestry since two generations per year will give two, instead of one, attack periods each summer. In addition to increasing the number of attacked trees the effect of the attacks may also be more severe, as Norway spruce is more susceptible to beetle attacks later in the summer. However, climate change will probably also change the phenology of Norway spruce and thus its susceptibility to attack by I. typographus and its phytopathogenic fungal associates. We are currently modelling how tree resistance varies with temperature and tree phenology in order to provide more well-founded advice to forest managers on the interaction between bark beetles and tree in a future climate.