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.
2012
Forfattere
Nicola Luchi Paolo Capretti Carl Gunnar Fossdal Mario Pazzagli Pamela PinzaniSammendrag
The development of new tools able to select specific plant tissue is crucial for gene expression studies. During the last years, the use of laser microdissection, mainly tested on herbaceous plant tissue, has been found to be a useful technique for these purposes. This method is poorly tested on woody species, and so far no studies of gene expression have been applied on forest trees.For this reason the present work proposes the optimization of a functional protocol using laser microdissection pressure catapulting (LMPC) and real-time reverse transcriptionpolymerase chain reaction (RT-PCR) in bark stem tissue of Norway spruce (Picea abies). Bark tissue fragments were collected from Norway spruce trees and sliced with a cryostat. RNA was extracted from both whole cross-sections and microdissected bark cells.The feasibility of the method was confirmed by the amplification of the -tubulin, an endogenous gene of P. abies, with efficiency comparable to that obtained from non-microdissected tissue. The proposed protocol, here adapted for bark tissue of woody species, represents a useful tool in a wide range of hosts that, unlike herbaceous plants, have scarcely been considered up to now.
Forfattere
Holger LangeSammendrag
We calculate entropy and complexity of runoff time series and artificially generated series with long-range correlations. Entropy and complexity of data series may be represented against each other in a two-dimensional diagram which we will refer to as Complexity-Entropy Causality Plane, or CECP. We use a recently developed framework for these two indicators based on order statistics. It is well-known that runoff, as all other environmental time series actually measured, is a mixture of deterministic (signal) and stochastic (noise) parts, the latter due to noise inherent in the measurement process and externally induced by natural processes. The distinction between signal and noise is notoriously difficult and subject to much debate. In our approach, the observed series are compared to purely stochastic but long-range correlated processes, the k noise, where k is a parameter determining the strength of the correlations. Although these processes resemble runoff series in their correlation behavior and may be even tuned to any runoff series by changing the value of k, the CECP locations and in particular the order pattern statistics reveals qualitative differences between runoff and k noise. We use these differences to conclude on the deterministic nature of the (short-term) dynamics of the runoff time series. The proposed methodology also represents a stringent test bed for hydrological models.
Sammendrag
Genomic sequencing gives us a tool to systematically and rapidly discover novel genes, how their products function in the cell, and explore their interactions. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by different wood protection systems during decay can be identified. This knowledge will give us a better understanding of the fungal degradation of wood and we can optimize wood protection systems. Hence, no single technique will give us the answer to all questions about the decay of wood we need to gather small pieces of the puzzle using different approaches. The aim of the present study was to investigate the effects of acetylation level on the growth of Postia placenta with regard to amount of total DNA and gene expression targeting six different genes. This paper presents preliminary results after 36 weeks of incubation. We found no mass loss in the acetylated samples treated to a high treatment level after 36 weeks of incubation in a modified monoculture soil-block test. The presence of P. placenta DNA and the absence of mass loss could indicate on an inability of the mycelia to establish a wood exploitation phase. The results also showed that P. placenta increased the expression of AlO (involved in production of H2O2), cytochrome P450 (related to breakdown of toxic compounds), and QRD (involved in generating biodegradative hydroxyl radicals via redox cycling) along the incubation time, growing on acetylated wood treated to a high treatment level.
Forfattere
Kjersti Holt HanssenSammendrag
Undersøkelser viser at snutebillene er til stede i alle områder i innlandsfylkene, selv om angrepsgraden varierer mye mellom feltene.
Forfattere
Lars Sandved DalenSammendrag
I over tre år, og sammen med 23 andre forskere fra 16 forskningsinstitusjoner i 11 land, har hun undersøkt DNA og pollen fra bunnen av innsjøer på Andøya og i Meråker i Nord-Trøndelag, og funnet at trær, som gran og furu, faktisk overlevde istiden for over 20 000 år siden.
Forfattere
Lars Sandved DalenSammendrag
God oversikt over skogressursene gir bedre utnyttelse og større verdiskaping. En ny metode gjør det nå mulig å beskrive også mindre skogområder ved hjelp av data fra tredimensjonale flyfoto.
Forfattere
Gisela Lüscher Michaela Arndorfer Katalin Balázs K.G. Bernhardt M. Bogers R.G.H. Bunce J.-P. Choisis Peter Dennis Wenche E. Dramstad Sebastian Eiter Gunnar Engan Wendy Fjellstad T. Frank Jürgen Friedel Ilse Geijzendorffer P. Gillingham Felix Herzog K.-J. Hülsbergen Philippe Jeanneret G. Jerkovich Rob Jongman Maximilian Kainz M.L. Oschatz Susanne Papaja-Hülsbergen Philippe Pointereau Jean-Pierre Sarthou M.K. Schneider Norman Siebrecht Sebastian WolfrumSammendrag
Det er ikke registrert sammendrag
Sammendrag
Phytophthora-arter er aggressive, sopplignende skadegjørere som fremmes av fuktig og mildt klima. I Norge er flere arter oppdaget på trær i paker eller skogholt nær hager. Varslede klimaendringer med økt temperatur og nedbør kan skape gode vekstforhold slik at flere arter kan etablere seg også i skogområder.
Sammendrag
Groundwater pollution by agrochemicals, degradation of soil quality and pollution of aquatic ecosystems by agricultural drainage waters have become an issue in the last decades. Flow processes in the vadose zone are closely related to these problems. In general, water flow in soils can be classified into two major categories: uniform and non-uniform (preferential) flow (In: U.S. National Committee for Rock Mechanics, Conceptual Models of Flow and Transport in the Fractured Vadose Zone, 2001, pp.149-187). The former describes a relatively slow movement of water through the porous soil matrix and can be modelled by Richard”s equation. The latter comprises all flow types where water bypasses a portion of the soil matrix and flows through localised (i.e. preferential) paths. Unlike uniform flow, preferential flow is hardly predictable because the assumptions of Richard”s equation of a homogeneous representative elementary volume characterised by a single value of water potential, water content and hydraulic conductivity are frequently violated (Eur J Soil Sci, 2007; 58:523-546)....
Forfattere
Harald BratliSammendrag
Det er ikke registrert sammendrag