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.
2010
Forfattere
Venche TalgøSammendrag
Phytophthora spp., powdery mildews, Neonectria sp. and others
Sammendrag
In 2009, Phytophthora cambivora was isolated from a bleeding beech in Bergen and Ph. plurivora from one in Stavanger. Ph. cambivora has previously been found on noble fir (Abies procera) in Norway and Ph. plurivora on rhododendron (Rhododendron spp.). In Stavanger, Ph. plurivora was also isolated from Norway maple (Acer platanoides) standing adjacent to the infected beech.
Sammendrag
Chalara fraxinea, causing ash dieback, was detected on common ash (Fraxinus excelcior) in Norway in May 2008, and is currently causing severe dieback of young and old trees in lower regions from south eastern to south western Norway. The Norwegian Food Safety Authorities have issued restrictions concerning movement of ash plants to non affected areas. At the Norwegian University of Life Sciences, a tree trial was recently established with the aim of selecting tree species for landscaping that are suitable for the Norwegian climate. Common ash is represented with two seed sources; Uppsala (Swedish) and Sauherad (Norwegian). In addition, the following ash species and cultivars are represented; green ash (F. pennsylvanica ‘Cimmzam", and F. pennsylvanica ‘Zundert"), narrowleaf ash (F. angustifolia ‘Raywood", syn. F. oxycarpa ‘Raywood"), and flowering ash (F. ornus ‘Mecsek"). By June 2010, they were all suffering from ash dieback except F. ornus ‘Mecsek". Due to severe dieback, F. excelcior ‘Nana" (‘Globosa") was removed from the trial in 2009.
Sammendrag
Internasjonal handel med planter er omfattande, og skadegjerarar fylgjer ofte med på lasset. Spesielt problematiske er artar i slekta Phytophthora som spreier seg til stadig nye område i verda. I skogsområde i sørvest England er det for tida ein epidemi som fører til masseøydelegging av lerk. Inntil nyleg kjente vi berre til Phytophthora-angrep på ulike jord- og hagebrukskulturar her i landet, men i 2009 vart det også funne symptom på bøk, lønn og bjørk i eit skogholt i Stavanger.
Sammendrag
Det er svært vanleg å bruka bark og flis til dekking mot ugras, som underlag på gangstiar eller anna i grøntanlegg. Dersom barken og flisa ikkje er varmkompostert, kan honningsopp (Armillaria spp.) fylgja med på lasset. Dette er ein vanleg skadegjerar i skog, spesielt på gran, men også i grøntanlegg gjer denne soppen meir skade enn mange er klar over.
Forfattere
Venche Talgø Maria Herrero Brita Toppe May Bente Brurberg Trude L. Slørstad Robert Thurston Arne StensvandSammendrag
I 2009 vart det funne mørke flekkar på stammane på fleire spisslønn, ein bøk og ei bjørk ved Byhaugen i Stavanger. Slike flekkar er typiske symptom ved angrep av Phytophthora-artar, og vert ofte omtala som blødande sår. På dei to førstnemnde tre-artane vart det stadfesta at skadane skuldast rotråte på grunn av Phytophthora plurivora. Sjukdomen er kjent frå fleire land i Europa, der han vert sett på som ein stor trussel både i skog og andre økosystem.
Forfattere
Christer MagnussonSammendrag
The recent spread of pinewood nematode (PWN) Bursaphelenchus xylophilus in Europe is a concern to Nordic countries. Since PWN may exist in trees free of symptoms its distribution becomes unclear. Commodities like pulpwood, particle wood (PW) and wood packaging material (WPM) could have hidden infections. Pulpwood offers obvious risks of transmission due to a possible presence of both PWN and its vectors (Monochamus spp.). Generally, PW is considered to pose a low theoretical risk due to absence of vectors, and WPM no risk if heat treated. Transmission of PWN from infested wood to trees has been demonstrated, and a recurrent use of PW on sports tracks may during one forest cycle result in transmission. PWN can survive for long periods in wood, and reported limited heat treatment capacities indicate that infested WPM already may circulate within the EU. In the Nordic region, pallet wood is a popular fuel and is stored at summer houses where direct contact with trees could cause transmission. In Nordic locations establishment of PWN is expected to cause damage only in hot summers. Even in a warmer climate the damage at least in a 50 yrs perspective is expected to be small, but costs of nematode control will be very high. In a short perspective effects on Nordic exports are small, but in a longer perspective new outbreaks of pine wilt disease in Europe could change export markets. Key Words: Pinewood nematode, Europe, trade risks, Nordic region
Forfattere
Christer MagnussonSammendrag
The spread of the pinewood nematode (PWN) Bursaphelenchus xylophilus in Europe is a threat to 36 million ha Nordic coniferous forests. In spite of a strict phytosanitary regulation of wood imports, the volumes and an unclear distribution of PWN could result in an introduction into the Nordic region. In the present climate expression of pine wilt disease is expected only in hot summers. Hence, the detection of PWN in the Nordic area is likely to remain unnoticed for a considerable period of time. In Fennoscandia more than 9000 samples have been analyzed from risk areas and risk commodities. The focus often has been on the breeding substrate of the vector insects in the genus Monochamus. A recent study on a simulated introduction in Norway (Økland et al in print) indicates that 14 years may elapse before detection by the present level of 400 samples annually. It was demonstrated that an earlier detection of PWN provided by an annual sample volume of 10 000 samples would still not be sufficient for successful eradication of PWN by 3 km radius clear-cuts. So, large sampling volumes and strict import regulations for PWN are highly important for the Nordic area. Økland, B.O. Skarpaas, M. Schroeder, C. Magnusson, Å. Lindelöw & K. Thunes 2010. Is Eradication of the Pinewood Nematode (Bursaphelenchus xylophilus) Likely? An Evaluation of Current Contingency Plans. Risk Analysis in print Key Words: Pinewood nematode, Nordic area, sampling, eradication, regulation
Forfattere
Christer MagnussonSammendrag
S.radicicola is a parasite of barley and grasses like Poa annua and P.pratensis. The life cycle of a Norwegian population of S.radicicola (Poa-race) is studied in the laboratory by inoculating newly germinated P.annua (cv. Leif) with 140 juveniles from field collected galls and keeping the plants at 25˚C and 16 hrs light period. Juvenile stages are separated based on genital development. The first stage (J1) has 1 cell, while the following stages J2, J3 and J4 has 2, 3 and 4 (or more) cells in their genital primordia. J1 (L = 310-350μm) moults in the egg and J2 (L = 330-400μm) is the hatching stage. Nematodes emigrating from field collected galls were all J3:s (L = 360-430μm), and moulted outside the gall to J4 (L = 210-500μm). The first stage to appear in newly formed galls is large J4 (L=500-870 μm), which moults within 5 days to adult (L=820-1980 μm). Egg-laying starts within 13 days and eggs hatch after 22 days. Juvenile development in eggs starts at 5˚C, and 640 degree days are required for completing one generation corresponding to about 30 days at 25˚C. This means that in Norway S.radicicola may have up to 3 generations per year. The fact that J3 exit the galls and the large J4 is the first stage present in newly formed galls makes us speculate that the induction of gall formation occurs from outside by pre-infective J4, which later infects and develop inside the gall. Key Words: Root gall nematode, Subanguina radicicola, Poa annua, life cycle, Norway
Sammendrag
I "Fusariumprosjektet" ved Bioforsk Plantehelse har vi i løpet av en 4 års periode (2006-2009) samlet inn kornprøver fra partier med norskprodusert havre og vårhvete med tilhørende opplysninger om klima og dyrkningsmessige forhold. Kornprøvene er videre analysert for innhold av 17 ulike mykotoksiner. Ved å sammenstille og analysere data og informasjon om de ulike kornprøvene, har vi kartlagt ulike faktorer som kan ha betydning for utvikling av mykotoksiner i kornet. Dataene er videre brukt for å utvikle varslingsmodeller for Fusarium-mykotoksiner i korn, og for utprøving av ulike hurtigmetoder som er utviklet for å måle innhold av mykotoksiner i korn.