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
Forfattere
Venche TalgøSammendrag
Det er ikke registrert sammendrag
Sammendrag
CSNN is common on Abies spp. both in the USA and Europe. To our knowledge the main focus on seeking an explanation to the problem has been on noninfectious/abiotic factors like nutrition and effect of shading. Thus, we decided to look into possible fungal infections on symptomatic needles. We examined samples from Nordmann fir (Abies nordmanniana) both in Norway and Austria. This resulted in a number of fungi.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
May-Guri Saethre Arnstein StaverløkkSammendrag
Funn av harlekinmarihøna Harmonia axyridis i Norge
Sammendrag
Forskere ved Skog og landskap og Universitetet for miljø- og biovitenskap (UMB) har, sammen med industrien, oppdaget at det er variasjoner i opptak av impregneringsvæske ved trykkimpregnering. Dette skyldes til dels forskjeller mellom furubestand. Den største forskjellen skyldes breddegrad. Det vil si at furu fra sørlige bredde grader lettere lar seg impregnere enn furu fra nordlige breddegrader.
Forfattere
Brita Toppe Maria Herrero May Bente BrurbergSammendrag
Fusarium foetens ble for første gang påvist i Norge i 2002 i Begonia x hiemalis. Deretter er betydlige angrep registrert i hiemalisbegonia, i den nye vertsplanten Begonia cheimanta (juleglede) og i den nye kultivaren Betulia. Utgang på mer enn 50% er observert i alle de tre vertsplantene i ulike gartneri. For identifikasjon av F. foetens ble det brukt real-time PCR basert på (mtSSU)rDNA.
Sammendrag
The last few years, increasing levels of DON (deoxynivalenol) have been recorded in Norwegian cereals, particularly in oats. In the same period, increased occurrence of F. graminearum has been reported in Norway as well as in the Western part of Europe. There may be several reasons for this change: Climate change, altered distribution of cereal cultivars, pathogen adaptation to cooler regions etc. We aim to clarify whether the increasing occurrence of F. graminearum in Norwegian cereals is connected to a change in the distribution of genotypes of this species. Fifty `old" F. graminearum isolates collected from Norwegian grown cereals during the 1990s will be compared to a similar number of `new" isolates collected in recent years (2005-2007). Isolates from Germany, Russia, Finland and the US will be used for comparisons. The genetic diversity of these about 110 isolates (50 `new", 50 `old" and 10 non-Norwegian isolates) will be investigated by AFLP (amplified fragment length polymorphism). These isolates will also be identified phylogenetically and characterised to chemotype. In addition, some selected isolates will be assessed for aggressiveness on wheat and specific characters potentially important for fungal distribution such as in vitro growth rate, spore production and perithecia formation.
Sammendrag
The last few years, increased prevalence of Fusarium graminearum has been reported in Norway as well as in the Western part of Europe. This increased occurrence of F. graminearum in Norway is confirmed by comparing a survey on F. graminearum prevalence during the 1990"s with recent data.
Forfattere
Guro BrodalSammendrag
Fusarium head blight (FHB) or scab, seedling blight and foot rot are widespread and destructive diseases of small grain cereals (wheat, barley, oats, rye and triticale) throughout the world. The main causal agents are Fusarium culmorum, F. graminearum, F. avenaceum, F. poae, F. sporotrichioides and Microdochium nivale. More recently also F. langsethiae, previously described as "powdery F. poae", seems to be widespread at least in Scandinavian countries, especially in oats. In addition to causing yield losses, FHB is of great concern because of the potential of these Fusarium species, except M. nivale, to produce a range of secondary metabolites known as mycotoxins in the grain. Mycotoxins cause a potential health risk when contaminated grain is consumed in human and animal food products. The development of FHB is, to a large extent, determined by climatic conditions. It is generally agreed that plants are most susceptible to FHB at anthesis and moist conditions during the anthesis period are important for infection. In hotter regions, F. graminearum is generally regarded as the most important species. In cooler areas, such as Northwest Europe, F. culmorum, F. poae, F. langsethiae and M. nivale has been of greater importance. However, recent investigations indicate that the incidence of F. graminearum has increased considerably in usually cooler regions, including Scandinavian countries. In Norway, a more aggressive and fast growing F. graminearum type was observed in 2004 in the oat cultivar Bessin. A number of seed lots of this cultivar showed severely reduced germination capacity, which was due to a large proportion of infected seed. Mycotoxin analyses of some of the lots showed very high contents of DON (e.g. 25-30 000 ppb). This "new" F. graminearum is now recorded from several areas and also in barley and wheat seed, however, mostly in low frequencies. Nevertheless some serious mycotoxin occurrences have been reported particularly in oats. Research is being carried out to determine if this strain is really new, and if it is likely that it was introduced into Norway by importing infected seeds. Seed health testing of wheat seed in Norway is routinely carried out on agar plates (PDA) and M. nivale and Fusarium spp. are recorded separately. A survey of infection frequencies in Norwegian spring wheat seeds harvested during the years 2000 " 2007 showed that the proportion of M. nivale has decreased whereas Fusarium spp. has increased. In general, the increased occurrence of FHB is believed to be caused by changed cultivation practice, i.e. cereal growing in monoculture over large areas in combination with conservation tillage, which leaves large amount of inoculum on the ground. Possible reasons for the increased occurrences of F. graminearum in cooler regions are the adaptation of the pathogen to cooler conditions and that cooler regions may have gradually become warmer due to possible climate change. Increased FHB is also connected to increased production of maize. Incidence and severity of FHB are often significantly greater when wheat follows maize than when wheat follows other crops. The species responsible for FHB can also cause seedling blight and foot rot. However, the epidemiological relationship between these three diseases is not clear. There is little evidence that seed infection leads to the production of significant quantities of primary inoculum for head blights. More research in this area is needed to understand the role of seed infection in spread and development of FHB. Will it be possible to reduce FHB and the mycotoxin threat with the use of healthy seed? If yes, how is it possible to produce seed without Fusarium?