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.
2007
Abstract
No abstract has been registered
Authors
Lena Finér Helja-Sisko Helmisaari Krista Lohmus Hooshang Majdi Ivano Brunner Isabella Børja Toril Drabløs Eldhuset Douglas L. Godbold Tine Grebenc Bohdan Konôpka Hojka Kraigher Merja Möttönen Mizue Ohashi J Oleksyn Ivika Ostonen V Uri Elena VanguelovaAbstract
Fine roots (2 mm) are very dynamic and play a key role in forest ecosystem carbon and nutrient cycling and accumulation. We reviewed root biomass data of three main European tree species European beech, (Fagus sylvatica L.), Norway spruce (Picea abies L. Karst.) and Scots pine (Pinus sylvestris L.), in order to identify the differences between species, and within and between vegetation zones, and to show the relationships between root biomass and the climatic, site and stand factors.The collected literature consisted of data from 36 beech, 71 spruce and 43 pine stands. The mean fine root biomass of beech was 389 g m-2, and that of spruce and pine 297 g m-2 and 277 g m-2, respectively. Data from pine stands supported the hypothesis that root biomass is higher in the temperate than in the boreal zone.The results indicated that the root biomass of deciduous trees is higher than that of conifers. The correlations between root biomass and site fertility characteristics seemed to be species specific. There was no correlation between soil acidity and root biomass. Beech fine root biomass decreased with stand age whereas pine root biomass increased with stand age. Fine root biomass at tree level correlated better than stand level root biomass with stand characteristics. The results showed that there exists a strong relationship between the fine root biomass and the above-ground biomass.
Authors
Leena Finér Heljä-Sisko Helmisaari Krista Lõhmus Hooshang Majdi Ivano Brunner Isabella Børja Toril Drabløs Eldhuset Douglas Lawrence Godbold Tine Grebenc Bohdan Konôpka Hojka Kraigher M.-R. Möttönen J. Oleksyn Ivika Ostonen V. Uri Elena Iordanova VanguelovaAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Karlsson Magnus Ari Hietala Harald Kvaalen Halvor Solheim Åke Olson Jan Stenlid Carl Gunnar FossdalAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Carl Gunnar Fossdal Ari M. Hietala Igor A. Yakovlev Halvor SolheimAbstract
The root-rot causing fungus Heterobasidion annosum senso lato is the most devastating pathogen of conifers in Europe. This pathogen enter Norway spruce trees trough the roots and colonizes 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. Twenty percent of the trees in Norwegian spruce stands tend to be infected and this pathogen that can colonize ten meters up inside the tree trunk, decaying the silvicultural most valuable part of the tree. Despite this high incidence of damage the tree has efficient defences against this pathogen and the attack is eventually fought off if present in the bark or living wood. The tree also has a defense against this internal attack (by Heterobasidion established in the heartwood expanding and invading outward toward the living sapwood) by forming a reaction zone; in this case the host defense is directed inwardly by the still living sapwood toward the central colonized wood. We have in the last years 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. We strive to study both partners in this pathosystem from a molecular perspective, and are now focusing on the pathogen and what fungal gene-products are being expressed during the colonization of the heartwood compared to those expressed close to the active host defense (reaction zone) using suppressive subtractive hybridization (SSH) followed by Real-Time RT PCR analysis. In addition the colonization profiles were followed on extracted gDNA using quantitative Real-Time PCR.
Authors
Nicolette Fouche Jolanda Roux Halvor Solheim Ronald N. Heath Gilbert Kamgan Nkuekam P. Chimwamurumbe K.G. Pegg Michael J. WingfieldAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The Norwegian Monitoring Programme for Forest Damage (OPS) has since its start registered damage to selected trees. The aim of the registrations has been to explain variations in crown density and crown colour. In answer to international requests, the Norwegian Forest and Landscape Institute has prepared a short guide to the determination of the most common forms of damage found in Norwegian forests...