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
Hans Geir Eiken Rune Andreassen Alexander Kopatz I WartiainenSammendrag
The use of non-invasive sampling of hairs and scats in wildlife genetics opens the possibility for sampling and analyzing living populations of brown bears (Ursus arctos). The aims of this study have been to develop a quality assured approach for genetic assignment of individual identity of brown bears and to generate a population database that can be used for research, conservation management and forensics. Non-invasive genetic sampling was performed by collection of scats and hairs in the field during the time period from 2004 to 2008. Hair traps were applied to collect hairs from bears in selected geographical areas in 2007 and 2008. Genotypes from 13 STR loci were determined for 232 Norwegian bears. Initial analysis of the entire sample indicated a high level of substructure, and the sample was divided in four geographically different populations consisting of 206 individuals for further validation of the markers. Ten STRs (G1D, G10L, Mu05, Mu09, Mu10, Mu15, Mu23, Mu50, Mu51 and Mu59) conformed to Hardy-Weinberg equilibrium expectations with only minor deviations, while the remaining three STR loci (G1A, Mu26 and G10B) were subjected to further molecular analysis. The average estimate of population substructure for Norwegian bears using 10 STRs (FST) was determined to be 0.1, while the estimate for inbreeding (FIS) was -0.02. Accounting for the FST-value, the average probability of identity (PIave) was 5.67 x 10-10 and the average probability of sibling identity (PIsib) was 1.68 x 10-4. Accreditation in accordance with the international standard ISO17025 was achieved for the described laboratory approach in 2009. We suggest that this approach and STR markers should also be considered to be used for other populations of brown bears in Northern Europe in order to ensure a common quality of the data as well as to facilitate exchange of information in conservation genetics.
Forfattere
Jens Rohloff Per Winge Jahn Davik May Bente Brurberg Keithanne Mockaitis Vladimir Shulaev Stephen K, Randall Atle M. Bones Muath AlsheikhSammendrag
In order to support functional genomics research in octoploid (Fragaria x ananassa Duch.) and diploid (F. vesca) strawberry, a customized Fragaria microarray chip was developed as a joint collaboration between Graminor Breeding Ltd. and NTNU. F. vesca cDNA sequences were provided by The Center for Genomics and Bioinformatics, Indiana University (an assembly of >3 million reads from GS-FLX Titanium - Roche/454 Life Sciences sequencing), and about 59,000 publicly available Fragaria EST sequences were uploaded from NCBI. In addition, ~190 Mb of preliminary draft genome sequences from F. vesca were provided by the Strawberry Genome Sequencing Consortium (courtesy to V. Shulaev). cDNAs used as templates for probe design were validated by BlastN against the F. vesca draft genome excluding cDNAs of microbial origin. Genes not represented in the cDNA collection were identified by screening F. vesca draft genome against protein sequences from Arabidopsis thaliana, Vitis vinifera, Ricinus communis and Populus trichocarpa. Exon sequences from genes not found in the cDNAs were included. In total, 43723 unique 60-mer probes were designed and the Agilent eARRAY tool was used to produce a 4x44k format microarray chip. Fragaria chip applicability and feasibility for transcriptional profiling was investigated using either abiotic (low temperature) or biotic (pathogenic fungi) stress treatment. Microarray data will be subsequently integrated with other omics data to address gene-regulatory networks and biological functions. Cold acclimation experiments were focused on short- and long-term effects in meristematic tissue, and revealed the up-regulation of ~100 cold-responsive genes (transcription factors, dehydrins, enzymes), and transcripts involved in starch breakdown and raffinose biosynthesis. Beside central metabolism, secondary metabolism was also strongly modulated as seen by changes in the expression of flavonoid biosynthesis-related genes. Time-course studies of transcriptional responses in F. vesca accessions showing contrasting resistance toward the pathogen Phytophthora cactorum are in progress, and will be presented in-depth.
Forfattere
Leif Egil Loe Atle Mysterud Erling L. Meisingset Vebjørn Veiberg Barbara ZimmermannSammendrag
Det er ikke registrert sammendrag
Sammendrag
Docks are among the most important perennial weeds in grasslands throughout the world and the need for more effective control methods is especially crucial in organic forage production. To find more effective control methods, field trials over 2 years at 4 Norwegian locations, were carried out mainly as a full-factorial design, including factors expected to reduce docks significantly. (i) Date of grassland establishment: may be important for preventing/decreasing the flush of seedlings from seeds as well as shoots from root fragments.(ii) False seedbed preparation: to decrease soil seed bank. (iii) Use of nurse crop (cover crop) to increase competitiveness against Rumex seedlings. (iv) Cutting the taproot, using a rotary tiller before ploughing, or the "dock-plough" (a skimmer modified to cut roots in the entire furrow width at ca 7 cm depth): as new shoots mostly come from the neck and the upper 5 cm of the taproot. (v) Ploughing depth and skimming: to decrease shoots from root fragments. Weed development was assessed as the number of emerging Rumex seedlings and plants sprouting from root fragments. Results indicated that frequently more plants emerged from seeds than from root fragments. Neither renewing the grassland in summer, nor the use of the rotary tiller or the "dock plough" reduced the number of docks in the renewed grasslands. The use of the false seedbed and nurse crop, at some locations and years, reduced the number of docks in the renewed grasslands. Deep ploughing (24cm) reduced the number of Rumex plants from roots by 65% percent compared to shallow ploughing (16cm). Furthermore, the use of a skimmer reduced the number of docks sprouting from roots by 28%. Among the investigated factors, competitiveness, false seedbed and ploughing depth, as well as ploughing quality, seems to be the most promising factors for reducing the number of docks in renewed grassland.
Forfattere
Chuan Li Heidi Rudi Jihong Liu Clarke Robert Wilson Robert Wilson M Cao Odd Arne RognliSammendrag
Det er ikke registrert sammendrag
Sammendrag
Currently, very little data exist on the exposure of soil biota to engineered nanoparticles (ENPs), in spite of soils being an important potential sink for ENPs. This is mainly due to difficulties in tracing ENPs in soils where natural nanoparticles are abundant. We used neutron activated ENPs as tracers and examined the exposure (uptake, excretion and internal distribution) of nanoparticles of cobalt (Co NPs 3.9 ± 0.8 nm) and silver (Ag NPs 20.2 ± 2.5 nm) in the earthworm Eisenia fetida, and compared this to soluble cobalt and silver salts. Accumulation patterns were highly different for cobalt and silver. Concentrations of cobalt in worms reached 88% and 69% of the Co ions and Co NPs concentrations in food, respectively, while corresponding values for Ag ions and Ag NPs were 2.3% and 0.4%. Both Ag NPs and Ag ions in earthworms were excreted rapidly, while only 32% of the accumulated Co ions and Co NPs were excreted within 4 months. High accumulation of cobalt was found in blood, and to a lesser extent in the digestive tract. Sequential extraction and centrifugal ultrafiltration provided useful information on metal speciation and bioavailability of Co NPs and Ag NPs.
Forfattere
Aksel Døving Arnfinn Nes Simen MyhreneSammendrag
Det er ikke registrert sammendrag
Forfattere
Kjersti Holt HanssenSammendrag
De siste årene har det blitt rapportert om stedvis kraftige angrep av gransnutebiller i foryngelsesfelt på Vestlandet og i Trøndelagsfylkene. Vi ønsket derfor å gjennomføre en undersøkelse av snutebilleskader i felt på Vestlandet og i Trøndelag. Til sammen 50 flater i kystfylkene Rogaland, Hordaland, Sogn og Fjordane, Møre og Romsdal, Sør-Trøndelag og Nord-Trøndelag ble undersøkt høsten 2009. Disse var plantet til i 2008 eller 2009, og det hadde ikke gått mer enn to sesonger siden hogst ved tilplantingen. På hvert felt ble alle kulturplantene på 20 sirkelflater á 20 m2 undersøkt for snutebillegnag og andre skader, og vitaliteten ble bedømt i fire klasser. For hvert felt ble variabler som høyde over havet, flatestørrelse, helling, eksposisjon og plantetype registrert.....
Sammendrag
All the Norwegian CLC2006 classes are documented through descriptive statistical “profiles” of the actual contents in each class. The CLC2006 profiles are worked through based on an overlay operation between CLC2006 and AR5 (under the timberline) and AR50 (above the timberline). Based on this dataset statistics are generated, that shows the percent distribution of AR5 and AR50 classes in each CLC2006 class. The study was carried out with funding from the Norwegian Space Centre.
Forfattere
Roman Gebauer Josef Urban Isabella Børja Vladimir Gryc H Vavrcik Daniel Volarik Petra RychteckaSammendrag
The drought stress presents a significant threat for the forest ecosystems. The climate change brings some extreme climatic conditions including longer and more common periods of the drought into the still more forest stands. Current forest management and consecutively wood processing industry in the Czech Republic is nowadays dependent mostly on the Norway spruce. In the same hand, Norway spruce is probably the most threatened tree species by the climate change. Therefore there is a demand for the suitable methodology to monitor the direct effect of the drought on the trees. Presented publication puts together different methods of the evaluation of the water stress and tries to assess their value for the study of the water stress. Of course, there are dozen of the methods to study the water stress. In this handbook we skipped the difficult and expensive techniques and focused rather on the simple methods, suitable for the field use. Methodology begins with the description of the meteorological measurements with current widely available instrumental techniques (i.e. measurements of the intensity of global radiation, air temperature and humidity, wind speed and precipitation) and continues with the monitoring of the soil water content and soil water potential. Then there is a focus on the direct effect of the water stress on the plant. We began with the plant root system since we believed that the fine roots were the most susceptible part of the tree. The focus was on their morphology, anatomy and biological activity. In the aboveground part of the tree we focused on the development of the hydraulic architecture of the tree on the microscopic level. This theoretical analysis was validated by the in-situ measurements of the sap flow. Direct and immediate effect of the water stress on the plant water status is described in the means of the plant water potential. Similarly to the hydraulic architecture we dealt with both the xylogenesis (on the cellular level) and the stem increment measured (on the tree level) by the logging band dendrometers. Finally we discussed the effect of the plant water status on the mineral nutrition of the tree. To conclude, none of the methods alone can implicate the complexity of the water stress, however the combination of the different views gives rather good insight on the tree condition and enable to predict the further tree development.