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.
1998
Forfattere
T. HofsvangSammendrag
Det er ikke registrert sammendrag
Forfattere
Franck Brignolas François Lieutier Daniel Sauvard Erik Christiansen Alan A. BerrymanSammendrag
Changes in phloem phenolic content of Norway spruce (Picea abies (L.) Karst.) clones were followed during the first 12 days of the reaction induced by phloem artificial inoculation with Ceratocystis polonica Siem., a bark beetle (Ips typographus L.) associated fungus. The aim was to confirm our previous results concerning the mechanisms of this reaction and the possible predictors of Norway spruce resistance to bark beetles and their associated fungi. The induced reaction was characterized by a slight decrease of tanning ability and an increase of ()-catechin concentration, which confirmed our previous observations. The relative resistance of the clones was first predicted using the predictors previously proposed. In addition, the first axis of the principal component analysis describing the phenolic content of all clones was used as a synthetic predictor (resistance axis). Related variables were also tested as predictors. Actual resistance of each clone was then measured, using mass inoculations of C. polonica, and was compared with the predictions. Four predictors were so validated: the resistance axis, tanning ability and isorhapontin concentration in uninoculated phloem, and ()-catechin concentration in the phloem 6 days after its inoculation. Phloem phenolic composition could thus be used to predict Norway spruce resistance to bark beetles and their associated fungi.
Forfattere
Tong ZhuSammendrag
Det er ikke registrert sammendrag
Forfattere
Olavi Junttila Jorunn E. Olsen Jarle Nilsen Inger Martinussen Thomas Moritz Maria Eriksson Olof Olsson Göran SandbergSammendrag
Resultatene viser at det er en signifikant effekt av havre PHYA genet på kulde tilpasning hos Populus. Dette indikerer at det kan være et kvantitativ forhold mellom konsentrasjonen på fytokrom genet og tilpasning til fotoperiode.
Forfattere
Olavi Junttila Jorunn Elisabeth Olsen Jarle Halvard Nilsen Inger Martinussen Thomas Moritz Maria Eriksson Olle Olsson Göran SandbergSammendrag
Photoperiodic effects on woody plants were reported already by Gardner and Allard in 1923 and comprehensive studies during the ’50s confirmed the role of photoperiod as an important environmental regulator of growth and growth cessation in many northern tree species (Nitsch, 1957; Wareing, 1956). In woody plants cessation of apical growth is a prerequisite for cold acclimation (Weiser, 1970) and photoperiod, as a factor controlling growth cessation, is therefore an important environmental signal for initiation of cold acclimation. In many cases a proper timing of acclimation and deacclimation, in respect to annual variation of temperature conditions, is more critical for winter survival than the maximum level of frost hardiness. Also in such coniferous species where cessation of apical growth is not controlled by photoperiod, short photoperiod is necessary for good cold acclimation, low temperature causes no or only a limited level of hardiness if combined with long day conditions (Schwarz, 1970; Aronsson, 1975; Christersson, 1978; Jonsson et al., 1981). Thus, photoperiod may have both an indirect, through induction of growth cessation, and a more direct influence on cold acclimation in woody plants.
Sammendrag
Concentrations of pigments in needles of yellowish Norway spruce (Picea abies (L.) Karst.) trees suffering from either N, Mg or K deficiency in field sites in southeast Norway are reported. The yellowish trees had a considerably lower (roughly 50%) pigment concentration, as well as a lower chlorophyll/carotenoid ratio, compared to the green trees within the same sites. Yellowing was interpreted as a general bleaching of colour, as well as a slight turn from the green (chlorophylls) towards yellow (lutein). Concentrations of pigments were highly intercorrelated. N deficiency was especially associated with low a-carotene concentrations. This was interpreted as a-carotene being the most sensitive pigment to stress. However, this pigment might be specifically sensitive to N deficiency. Carbohydrate concentrations were slightly higher in yellowish trees.
Forfattere
Bjørn KløveSammendrag
Det er ikke registrert sammendrag
Forfattere
Astrid JohansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Astrid JohansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Espen Lydersen Valter Angell Odd Eilertsen Thorbjørn Larssen Jan Mulder I.P. Muniz Hans Martin SeipSammendrag
Det er ikke registrert sammendrag