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.
2004
Forfattere
Eivind VangdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Eivind VangdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Eivind VangdalSammendrag
Det er ikke registrert sammendrag
Forfattere
Karl Thunes John Skartveit Ivar Gjerde Josef Stary Torstein Solhøy Arne Fjellberg Sverre Kobro Sueo Nakahara R. Zur Strassen Gijsbertus Vierbergen Ryszard Szadziewski Daniel V. Hagan William. L. Grogan Jr Terje Jonassen Kjetil Aakra Johannes Anonby Lita Greve Berend Aukema Kai Heller Verner Michelsen Jean-Paul Haenni Alexandr F. Emeljanov Per Douwes Kai Berggren Jutta Franzen R. Henry L. Disney Sabine Prescher Kjell Arne Johanson Boris Mamaev Sigitas Podenas Stig Andersen Stephen D. Gaimari Emilia Narchuk Geir Einar Ellefsen Søli Laszlo Papp Fred Midtgaard Arild Andersen Michael von Tschirnhaus Gerhard Bächli Kjell Magne Olsen Hans A. Olsvik Mihaly Földvari Jan Emil Raastad Lars Ove Hansen Per DjursvollSammendrag
Det er ikke registrert sammendrag
Forfattere
Fadi Suliman Helen French Lars Egil Haugen Petter D. Jenssen Bjørn KløveSammendrag
Det er ikke registrert sammendrag
Forfattere
Branka Barl Steinar Dragland Ivan SalamonSammendrag
Plantenes produksjon av bioaktive stoffer er sterkt påvirket av genetiske forskjeller og vekstforhold. I denne oversikten er det vist at også næringstilgangen kan ha betydning i denne forbindelse. Det er vist eksempler fra peppermynte, kamille, prikkperikum og puprpursolhatt.
Sammendrag
Using information from a regional survey of vascular plants of 130 sites in western Norway, a selection of sites based on a heuristic iterative complementarity-based nature reserve selection procedure was performed. The results indicate that conservation of traditionally managed hay meadows is of major importance as they contributed 60.1% of all native species recorded; afforested grasslands (deciduous woodlands < 70 years old) contributed 26.8%, whereas artificially fertilized hay meadows and intensively cultivated grasslands taken together contributed 13.1% of the species. The species composition of the meadows was significantly nested. Thus, if you conserve the most species-rich meadows, you also conserve most of the species in the less species-rich meadows. Nestedness in meadows was significantly correlated with within-meadow habitat diversity and soil pH. The most species-rich meadows were traditional meadows, characterized by high habitat diversity and high soil pH. These meadows will support nearly all species including habitat specialists and regionally rare species, whilst artificially fertilized hay meadows only support the generalist subset, i.e. common species. Area was not significantly correlated with nestedness suggesting that it is more important to cover many habitats than to preserve large traditional meadows just because they are large.
Forfattere
Carl Gunnar Fossdal Øystein Johnsen Nina Elisabeth Nagy R Baumann Jørgen A.B. Mølmann Tore SkrøppaSammendrag
Introduction: Survival and competitive successes of boreal forest trees depend on a balance between exploiting the full growing season and minimising frost injury through proper timing of hardening in autumn and dehardening in spring. Our research indicates that the female parents of Norway spruce adjust these timing events in their progeny according to the prevailing temperature conditions during sexual reproduction. Reproduction in a cold environment advances bud-set and cold acclimation in the autumn and dehardening and flushing in spring, whereas a warm reproductive environment delays these progeny traits by an unknown non-Mendelian mechanism. We are now looking for molecular mechanisms that can explain this “epigenetic” phenomenon. Material and methods: We have performed identical crosses with the same Norway spruce (Picea abies) parent, as discussed by Skrøppa & Johnsen (1994) and Johnsen et al. (1995), in combination with timed temperature treatments during shorter and longer periods from female meiosis, pollen tube growth, syngamy and embryogenesis and tested the progenies for bud-set and frost hardiness. We have followed the transcription of the spruce phytochromes PHYO, PHYP and PHYN and the class IV chitinase PaChi4 using Quantitative Multiplex Real-Time PCR. Results and conclusions: The effect of temperature on Adaptive properties is most likely a response to accumulated heat during embryogenesis and seed maturation. Our first attempt to look for a molecular mechanism has revealed that transcription of PHYO, PHYP and PHYN and the class IV chitinase PaChi4 (relative to alphaTubulin) all show higher transcription levels in progenies born under cold conditions than their full-sibs born under warmer conditions. This result is consistent with preliminary findings that methylation of cytosine in total DNA is higher in progenies reproduce under warm conditions than their colder full-sib counterparts. If these observations are related to methylation or other epigenetic effects, we may explain why progenies with a memory of a past time cold embryogenesis are more sensitive to short days than their full-sibs with a warmer embryonic history.
Forfattere
Carl Gunnar Fossdal Øystein Johnsen Rüdiger Baumann Jørgen A. Mølmann Ola Gram Dæhlen Nina Elisabeth Nagy Tore SkrøppaSammendrag
Research indicate that the female parents of Norway spruce adjust these timing events in their progeny according to the prevailing temperature conditions during seed development. Reproduction in a cold environment advances bud-set and cold acclimation in the autumn and dehardening and flushing in spring, whereas a warm reproductive environment delays these progeny traits by an unknown non-Mendelian mechanism. We have performed identical crosses in combination with timed temperature treatments during shorter and longer periods from female meiosis, pollen tube growth, syngamy and embryogenesis, tested the progenies for bud-set and frost hardiness, and concluded that the effect of temperature most likely is a response to accumulated heat during embryogenesis and seed maturation. Our first attempt to look for a molecular mechanism has revealed that transcription of PHYO, PHYP and PHYN and the class IV chitinase PaChi4 (using RealTime PCR) all show higher transcription levels in progenies born under cold conditions than their full-sibs born under warmer conditions. This result is consistent with preliminary findings that methylation of cytosine in total DNA is higher in progenies reproduce under warm conditions than their colder full-sib counterparts. If these observations are related to methylation, we may explain why progenies with a memory of a past time cold embryogenesis are more sensitive to short days than their full-sibs with a warmer embryonic history.
Sammendrag
Utvalgt Forelesning/Selected Talk: Survival and competitive successes of boreal forest trees depend on a balance between exploiting the full growing season and minimising frost injury through proper timing of hardening in autumn and dehardening in spring. Our research has shown that the female parents of Norway spruce adjust these timing events in their progeny according to the prevailing temperature conditions during sexual reproduction. Reproduction in a cold environment advances bud-set and cold acclimation in the autumn and dehardening and flushing in spring, whereas a warm reproductive environment delays these progeny traits by an unknown non-Mendelian mechanism. We have performed identical crosses in combination with timed temperature treatments during shorter and longer periods from female meiosis, pollen tube growth, syngamy and embryogenesis, tested the progenies for bud-set and frost hardiness, and concluded that the effect of temperature most likely is a response to accumulated heat during embryogenesis and seed maturation. Our first attempt to look for a molecular mechanism has revealed that transcription of PHYO, PHYP and PHYN and the class IV chitinase PaChi4 (using RealTime PCR) all show higher transcription levels in progenies born under cold conditions than their full-sibs born under warmer conditions. This result is consistent with preliminary findings that methylation of cytosine in total DNA is higher in progenies reproduce under warm conditions than their colder full-sib counterparts. If these observations are related to methylation, we may explain why progenies with a memory of a past time cold embryogenesis are more sensitive to short days than their full-sibs with a warmer embryonic history.