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.
2001
Forfattere
M. Tojo T. Hoshino Maria Herrero Sonja Klemsdal Anne-Marte TronsmoSammendrag
Pythium ultimum var. ultimum was isolated from carrot seedlings with damping off and from soil in a greenhouse on Spitsbergen Island, Svalbard. The fungus caused severe damping off of carrot, cucumber and tomato seedlings after artificial inoculation. The rDNA ITS sequences were identical to isolates from Canadian and Japanese isolates. The pathogen in the greenhouses on Svalbard was probably introduced from temperate regions. This is the first record of P.ultimum var. ultimum with in the Artic zone
Forfattere
Jahn DavikSammendrag
En rapport om status i Planteforsks jordbærforedling ved utgangen av 2000. De mest lovende nummersortene presenteres. Resultatene fra 1999 ble i stor grad bekreftet i 2000 og dette er lovende med tanke på lansering av nye sorter i jordbær .
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Det er ikke registrert sammendrag
Forfattere
F Schlyter Mats Svensson Qing-He Zhang Milos Knizek Paal Krokene Per Ivarsson G BirgerssonSammendrag
Det er ikke registrert sammendrag
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In 1996, 7000 ha of pine forests were defoliated by the pine looper Bupalus piniaria in south-western Sweden.The susceptibility of trees of different defoliation classes (0, 30, 60, 90 and 100% defoliation) to beetle-vectored blue-stain fungi was tested in inoculation experiments.Forty and 120-year-old Scots pine trees were inoculated with `single\", i.e. a few inoculations of Leptographium wingfieldii and Ophiostoma minus, two blue-stain fungi associated with the pine shoot beetle Tomicus piniperda. The young trees were also \"mass\" inoculated with L. wingfieldii at a density of 400 inoculation points per m2 over a 60 cm stem belt.Host tree symptoms indicated that only trees with 90100% defoliation were susceptible to the mass inoculation.Single inoculations did not result in any consistent differences in fungal performance between trees of different defoliation classes, regardless of inoculated species or tree age class.Leptographium wingfieldii produced larger reaction zones than O. minus, and both species produced larger lesions in old than in young trees.As beetle-induced tree mortality in the study area occurred only in totally defoliated stands, mass inoculations seem to mimic beetle-attacks fairly well, and thus seem to be a useful tool for assessing host resistance.As even severely defoliated pine trees were quite resistant, host defence reactions in Scots pine seem to be less dependent on carbon allocation than predicted by carbon-based defence hypotheses.
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2000
Forfattere
Lars Sandved Dalen Carl Gunnar Fossdal Inger Heldal Nina Elisabeth Nagy Praveen Sharma Geir Østreng Anders Lönneborg Øystein JohnsenSammendrag
Plants are sessile and have to adjust to the prevailing environmental conditions of their surroundings. This has led to a development of a great plasticity in gene regulation, morphogenesis, and metabolism. Adaptation and defence strategies involve the activation of genes encoding proteins important in the acclimation or defence towards the different stressors.Some of the molecular responses to biotic and abiotic stress factors such as pathogenic fungi or drought are specific, but it has also been shown that similar genes are acitvated by several stressors.At the Norwegian Forest Research Institute we are currently developing a diagnostic tool using the induction pattern of several selected genes from Norway spruce to use as a fingerprint for different types of biotic and abiotic stress. The ultimate goal of this project is to be able to identify unique mRNA expression patterns specific for different stressors such as heat, cold, drought, pathogens etc.In order to study the induction pattern expressed under biotic and abiotic stress, Norway spruce seedlings grown on glass beads in a phytotron we have treated with drought, a root pathogenic fungi (Rhizoctonia sp.), and a combination of drought and the root fungal pathogen.Physiological measurements of height, weight, ion leakage, gas exchange, and chlorophyll fluorescence are taken troughout the experiment. In addition, we have used light and electron microscopy, and immunolocalization to study structural cell and tissue changes. The results so far show great variance in the expression patterns between treatments and over time.