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.
2003
Authors
Petter NilsenAbstract
No abstract has been registered
Authors
J. BerghAbstract
No abstract has been registered
Authors
Ari M. Hietala Kari Korhonen R. SenAbstract
Strains of Ceratobasidium bicorne (anamorph uninucleate Rhizoctonia) causing root dieback in nursery-grown conifer seedlings were fruited in the laboratory and the pairing interactions among sibling, single-basidiospore progeny were investigated.No mating reactions were observed. Instead, a high frequency of somatic incompatibility was observed in progeny pairings, indicated by a killing reaction in hyphal anastomosis and by formation of a demarcation line. The F1 progeny could also be fruited, and the level of somatic incompatibility within the F2 progeny remained high, even if lower than in the F1 progeny.The interaction types in pairings within a family of progeny were in all respects similar to those between field isolates, indicating that the species is homothallic. The uninucleate condition of vegetative cells and the basidial characteristics now observed would indicate homokaryotic fruiting, but the possibility of pseudohomothallism remains.We are presently not able to provide an explanation for the mechanism promoting somatic incompatibility in this species, but it seems likely that the classic heterogenic model of somatic incompatibility recognised in basidiomycetes is not applicable here. Alternative mechanisms are discussed.
Authors
Halvor Solheim Kåre Olav VennAbstract
No abstract has been registered
Authors
Holger LangeAbstract
No abstract has been registered
Authors
John DeromeAbstract
No abstract has been registered
Authors
Petter NilsenAbstract
No abstract has been registered
Authors
Kjell Andreassen Stein TomterAbstract
Distance-independent individual tree growth models based on about 30,000 observations from the National Forest Inventory and the Norwegian Forest Research Institute have been developed for the main tree species in Norway.The models predict 5-year basal area increment over bark for trees larger than 5cm at breast height. Potential input variables were of four types: size of the tree, competition indices, site conditions, and stand variables including species, mixtures and layers. The squared correlation coefficient (R2) varied from 0.26 to 0.55.The accuracy of the models was tested by comparing the individual tree models with Norwegian diameter increment models. The accuracy is similar, but individual tree models forecast diameter distributions directly. The inclusion of species mixture and layer as variables increases the reliability of the models in mixed and in uneven-aged stands
Authors
Øystein Johnsen Carl Gunnar Fossdal Rüdiger Baumann Jørgen A. Mølmann Ola Gram Dæhlen David ClaphamAbstract
No abstract has been registered
Authors
Øystein JohnsenAbstract
No abstract has been registered