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.
2007
Forfattere
Karlsson Magnus Ari Hietala Harald Kvaalen Halvor Solheim Åke Olson Jan Stenlid Carl Gunnar FossdalSammendrag
Det er ikke registrert sammendrag
Sammendrag
In spring 2002, extensive damage was recorded in southeast Norway on nursery-grown Norway spruce seedlings that had either wintered in nursery cold storage or had been planted out in autumn 2001. The damage was characterised by a top shoot dieback. Two visually distinct types of necroses were located either on the upper or lower part of the 2001-year-shoot. Isolations from the upper stem necroses rendered Gremmeniella abietina, while Phomopsis sp. was isolated mostly from the from the lower stem necroses. RAMS (random amplified microsatellites) profiling indicated that the G. abietina strains associated with diseased nursery seedlings belonged to LTT (large-tree type) ecotype, and inoculation tests confirmed their pathogenicity on Norway spruce seedlings. Phomopsis sp. was not pathogenic in inoculation tests, this implying it may be a secondary colonizer. We describe here the Gremmeniella - associated shoot dieback symptoms on Norway spruce seedlings and conclude that the unusual disease outburst was related to the Gremmeniella epidemic caused by the LTT type on large pines in 2001. The role of Phomopsis sp. in the tissue of diseased Norway spruce seedlings is yet unclear.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Norsk institutt for skog og landskap har fokusert på hvilke effekter et endret klima kan få på granbarkbillen. Dette er den første av to artikler som gjengir noen av resultatene og hva de kan bety for norsk skog. Hyppigere stormer og tørkeperioder vil gi hyppigere utbrudd, men utbruddene kan komme til å bli mer kortvarige. Bestandsnivået til granbarkbillen svinger ofte i takt i landsdeler som rammes av de samme stormene. En viktig praktisk konsekvens av denne samvariasjonen over store områder er at skogskjøtseltiltak må skje på stor skala for å ha ønsket effekt.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Model simulations show that an increased frequency in storms and drought periods may result in more frequent and shorter outbreaks of bark beetles. Warmer summers can result in two bark beetle generations per summer instead of one, giving bark beetles the opportunity to attack forests twice in a single year.
Forfattere
Christer Magnusson Karl Thunes Hans Nyeggen Hans Overgaard Trond Rafoss Solveig Haukeland May Bente Brurberg K. A. Strandenæs Bjørn Økland Bonsak HammeraasSammendrag
The detection in 1999 of the pine wood nematode (PWN), Bursaphelenchus xylophilus, in Portugal triggered survey activities in many European countries. With the assumption that PWN would reach frequency 10 times lower than the native B. mucronatus and the requirement of a 95 % confidence limit suggested 2 995 samples to be required for a safe statement on the absence of PWN from the territory surveyed. Samples were taken from 10 circular areas with 50 km diameter erected from a point of import of risk materials. In the period 2000-2006 3 165 wood samples, 2 880 from Pinus sylvestris, 279 from Picea abies and 6 from unknown wood, were collected from 446 logging sites, in 84 municipalities and 13 counties. Of the total material 85 % of the samples came from cutting wastes, timber or lying trees. Wood showing signs of insect activity (incl. Monochamus) formed 73 % of the total material. Nematodes were recorded in 85 % of the samples. The order Rhabditida was most frequent, followed by the orders Aphelenchida, Tylenchida and Dorylaimida. Rhabditid nematodes were equally frequent in pine and spruce, while Aphelenchida (Aphelenchus, Aphelenchoides, Cryptaphelenchus, Seinura and Bursaphelenchus) and Tylenchida (Filenchus, Lelenchus, Ditylenchus, Deladenus and Nothotylenchus) tended to be more common in pinewood. Aphelenchoides was the most common genus. The genus Bursaphelenchus occurred in 1 % of the samples. B. mucronatus was detected in 0,3 % of the samples and most often in cutting waste of pine. The pine wood nematode (PWN), B. xylophilus, was not detected in this survey. The unexpected low natural occurrence of B. mucronatus indicates that the number of potential niches for PWN also is lower than expected, and hence it will be necessary to continue this surveillance program to reach 10 000 samples. The present zone sites in central and south-eastern Norway will be supplemented with 1-2 zone sites in southwestern region of the country. In the future these zone sites will function as permanent observation areas. Care will also be taken to collect all samples from detached wood with signs of Monochamus activity.
2006
Sammendrag
Klumprot er den mest skadelige sykdommen på korsblomstrede kulturplanter. Påvisning av klumprotsmitte i jord og vann er vanskelig og krever omfattende planteforsøk (bioassay) som det tar minimum 6-8 uker å gjennomføre. Vi har utviklet en hurtigtest for påvisning av klumprotsmitte i småplanteproduksjon og i felt av korsblomstrede kulturplanter.
Sammendrag
Det er ikke registrert sammendrag