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.
2002
Abstract
No abstract has been registered
Authors
Erlend Ystrøm Haartveit Per Otto FlæteAbstract
Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) were measured on lumber from trees originating from four stands in each of the countries Norway and Sweden. Half of the stands were monocultures of Norway spruce while the remainder were mixed stands of Norway spruce and birch species.No significant differences in MOE and MOR were found between Norway spruce lumber grown in monocultures and lumber originating from mixed stands. Furthermore, there were no significant differences between the two groups concerning wood density, mean annual ring width and diameter of the largest knot in each log.These three variables also yielded similar models for lumber originating from monocultures and mixed stands, respectively, when used as independent variables in simple regression models for MOE and MOR.PLS1 regression models, with a X-matrix of variables measurable with simple equipment on trees and logs, were used to sort logs according to predicted values of MOE and MOR. The models show promising results with respect to pre-sorting of logs in order to create a better fit between the quality of logs and the expected properties of the final products.When sorting logs, a high percentage is correctly classified, and the cumulative distributions of the two groups resulting from sorting are clearly different. Hence, PLS1 regression models using simple measurements on trees and logs seems potentially useful for predictions of MOE and MOR without the use of advanced technical equipment.
Abstract
A quantitative multiplex real-time PCR procedure was developed to monitor the dynamics in Norway spruce (Heterobasidion annosum) pathosystem. The assay reliably detected down to 1 pg of H. annosum DNA and 1 ng of host DNA in multiplex conditions. As a comparative method for quantifying fungal colonization,we applied the ergosterol assay. There was a very high correlation between the results obtained with the two methods, this strengthening the credibility of both assays. The advantages and disadvantages of these assays are discussed.
Authors
Halvor Torgersen Torstein LislandAbstract
No abstract has been registered
Authors
Toril Drabløs Eldhuset Arne SandnesAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Michael Weber Walter Schönenberger Gerhard Weiss Petter NilsenAbstract
No abstract has been registered
Authors
S. Kobro Halvor SolheimAbstract
No abstract has been registered
Authors
Halvor SolheimAbstract
No abstract has been registered
Authors
Lars Sandved Dalen Carl Gunnar Fossdal R. Bhalerao John Beck Jensen Teemu H. TeeriAbstract
Trær dekker over en tredjedel av jordas landareal og står for over to tredjedeler av den globale fotosyntesen. Barskogen i Alaska, Canada, Russland og Norden spenner over 1,2 milliarder hektar og utgjør en fjerdedel av det samlede landarealet til boreal og temperert skog. Mer enn 50% av landarealet i Norden er dekket av skog, for det meste barskog. Det er derfor svært viktig å skaffe kunnskap om bartrærnes responser til biotiske og abiotiske faktorer - både vitenskaplig men også fra et praktisk ståsted. Å samle såkalte Expressed sequence tags (ESTs) utgjør en viktig del av funksjonell genomforskning. Tilfeldig utvalgte cDNA-kloner blir delvis sekvensert, og EST-ene gjenspeiler sammensetningen og nivået på genuttrykket i det vevet som analyseres. I jakten etter interessante genprodukter og muligheter for å kunne studere genuttrykket i gran - den mest vanlige og økonomisk sett viktigste arten i de nordiske skoger - har vi startet et eget EST-prosjekt sammen med samarbeidspartnere i Finland og Sverige. Så langt har vi sekvensert ~3500 cDNA-kloner basert på mRNA isolert fra nåler og cellekulturer. Her presenterer vi frekvensen av de ulike EST-ene, deres sannsynlige funksjon og funksjonelle klassifisering. Målet vårt er å sekvensere ytterligere 20 000 - 30 000 cDNA-kloner fra veddannende vev, fra frøplanter utsatt for tørke, lave temperaturer, patogeninfeksjon etc. samt fra cellekulturer. Vårt langsiktige mål er å utvikle en velkurert og annotert samling av grankloner som kan brukes i forbindelse med mikromatrisestudier.