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Publikasjoner

NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.

2008

Sammendrag

Edellauvtreet alm (Ulmus glabra) har en vid utbredelse i Norge, men i et begrenset område er alm rammet av en alvorlig sykdom, den såkalte almesjuken. Dette er en viktig årsak til at alm ble rødlistet i 2006. Gjennom årene har mye blitt gjort for å kartlegge og begrense utbredelsen av sykdommen. Nylig har også viktige sider ved almens genetikk blitt studert. Denne folderen oppsummerer resultatene fra disse undersøkelsene. Brosjyre fra Skog og landskap, 3/2008 Norsk Genressurssenter

Sammendrag

An international EU/Interreg III Kolarctic project `Development and implementation of an environmental monitoring and assessment program in the joint Finnish, Norwegian and Russian border area`, was carried out during 2003–2006 as a joint undertaking between Norwegian, Finnish and Russian research institutes and environmental authorities. The aim of the terrestrial ecosystem sub-project of the Pasvik project was to develop and implement a monitoring and assessment programme for terrestrial ecosystems in the joint Finnish, Norwegian and Russian border area...

Sammendrag

Wood based products come from a renewable resource playing an important part of the carbon cycle and are therefore regarded environmentally friendly compared to many other alternatives. We might therefore expect a more intensive use of the timber resource in the future. An increase in the supply and net value of timber products from a given area requires more intensive and cost efficient forest management. However, a faster growth rate in general and an increase in the juvenile wood proportion specifically, might come in conflict with the desirable wood quality. Tree breeding programs for Norway spruce (Picea abies L. Karst.) aim to follow up the general demands by providing forestry with plant materials that have superior growth and high wood quality. It is therefore important to establish a better knowledge of the potential of improving wood quality characters in this species through breeding. Characteristics important for structural strength and dimensional stability in conifers are wood density, spiral grain, microfibril angle (MfA) in the S2 layer in the secondary cell wall, branch characteristics and stem straightness. We have studied the genetic variation and correlation patterns for these traits and the direct end-use performance of clearwood samples in terms of stiffness (MOE) and strength (MOR) in four studies of Norway spruce (Paper I-IV). Wood quality traits of defect free wood were studied in Paper I and II. The materials used were 28 and 29 year old progeny trials planted in South East Norway on fertile soils. Significant genetic variation was found for wood density, MfA and spiral grain in both studies (p < 0.05). MOE and MOR, measured by static bending, were studied in one of the materials and the genetic variation was found to be highly significant (p < 0.01). There was also significant genetic variation (p < 0.05) in MOE estimated (MOEest) from wood density and the x-ray diffractometry pattern from the S2 layer obtained by SilviScan®-3. Genetic parameters were estimated in Paper II with large standard errors. The parameters must therefore be used with caution and preferably with support from other studies. We could confirm earlier studies of high genetic variation and low genotype by environment interactions (GxE) for wood density and spiral grain. Parameter estimates for MfA and MOEest, from one site, suggest that these are under moderate to strong genetic control in Norway spruce. Phenotypic correlations between growth traits (height and diameter growth) and wood quality traits were negative for wood density, positive for MfA and negative for MOEest. Genetic relationships showed the same trends for diameter growth, but not for height growth. The genetic and environmental variation in branch characteristics (Paper III and IV) were studied in three sets of progeny trials that were 22, 28 and 29 years old from planting. Stem straightness was studied in the 22-year old trial only. The branch diameter was highly influenced by site index and spacing. Number of branches formed and stem straightness seems to be under stronger genetic control. Individual tree heritabilities for growth traits, branch diameter and stem straightness were estimated in the 22-year old progeny trial planted at two sites. The trials were planted with different spacing, which allowed us to study genotype by spacing interactions. Heritability for growth traits and branch diameter across sites were moderate (0.14 - 0.19) compared to the higher values found for stem straightness (0.28). GxE, and thereby genotype by spacing interactions were not important for any of the traits. Heritability for number of branches, estimated from one of the sites, was 0.24. There was a strong and positive genetic correlation between growth traits and branch diameter. The presence of genetic variation for most wood quality traits suggests that these can be improved by tree breeding. However, genetic correlations with growth traits indicate that selection solely for growth might have adverse effects on wood quality. It is therefore important to balance the gain in growth and wood quality. Implementation of several adversely correlated traits in a breeding program reduces its efficiency. It is therefore essential that tree breeding, silvicultural practices and forest industrial needs interact when developing tree breeding programs to obtain an optimal strategy for selection and utilization of improved plant materials.

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Sammendrag

Kjempebjørnekjeks er en fremmed art i Norge. Arten har negativ virkning på stedegent biologisk mangfold, og det er derfor behov for tiltak for å unngå ytterligere spredning. Plantene kan bekjempes med glyfosat (Roundup) eller ved oppgraving av rotstokker i mindre bestander. Avkutting av stengler eller skjermkutting fører til ny vekst eller nydannelse av blomsterknopper. Plantesaft kan, i kombinasjon med sollys, gi forbrenningsskader på hud.

Sammendrag

Kjempebjørnekjeks er en fremmed art i Norge. Arten har negativ virkning på stedegent biologisk mangfold, og det er derfor behov for tiltak for å unngå ytterligere spredning. Plantene kan bekjempes med glyfosat (Roundup) eller ved oppgraving av rotstokker i mindre bestander. Dersom en ønsker å beholde en bunnvegetasjon av grasarter, er lavdosemidlene Harmony eller Harmony Plus effektive. Avkutting av stengler eller skjermkutting fører til ny vekst eller nydannelse av blomsterknopper.