Hopp til hovedinnholdet

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.

2017

Til dokument

Sammendrag

Nighttime ultraviolet (UV) radiation, if applied properly, has a significant potential for management of powdery mildews in many crop species. In this study, the role of growth light duration, irradiance, a combination of both (daily light integral) and light spectral quality (blue or red) on the efficacy of UV treatments against powdery mildew caused by Podosphaera xanthii and the growth performance of cucumber plants was studied in growth chambers. Increasing daily light integral provided by high-pressure sodium lamps (HPS) decreased efficacy of nighttime UV treatments against P. xanthii, but it increased plant growth. Furthermore, the efficacy of nighttime UV decreased when day length was increased from 16 to 20 h at a constant daily light integral. The efficacy of nighttime UV increased if red light was applied after UV treatment, showing the possibility of day length extension without reducing the effect of UV. Increasing the dose of blue light during daytime reduced the efficacy of nighttime UV in controlling the disease, whereas blue deficient growth light (< 6% of blue) caused UV mediated curling of young leaves. Furthermore, application of blue light after nighttime UV reduced its disease control efficacy. This showed the importance of maintaining a minimum of blue light in the growth light before nighttime UV treatment. Findings from this study showed that optimization of nighttime UV for management of powdery mildew is dependent on the spectral composition of the photosynthetically active radiation.

Til dokument

Sammendrag

Post-stratified model-assisted (MA) and hybrid (HY) estimators are used with repeated airborne laser scanning (ALS) strip sampling and national forest inventory field data for stratum-wise and overall estimation of aboveground biomass (AGB) stock and change. The study area covered the southern portion of the Hedmark County in Norway. Both MA and HY estimation substantially reduced the uncertainty in AGB change when compared with estimation using the field survey only. Relative efficiencies (relative variance) of 4.15 (MA) and 3.36 (HY) for overall estimates were found. The results suggest the MA estimator for single-time estimation and the HY as more appropriate for change estimation by cover class. With the HY estimator, a nested post-stratification scheme is demonstrated, combining cover classes with change classes, which enables detailed reporting for change according to cause within each cover class, and has the potential to improve the estimation precision. Finally, parametric bootstrapping is demonstrated as an empirical alternative to estimate the model-error component in the HY estimator. The model error estimated with parametric bootstrapping converged to the analytically determined value of the HY estimator within 1000 bootstrap samples.

Til dokument

Sammendrag

In-depth metabolic profiling, also termed metabolomics, provides detailed information about the biochemical phenotype of an organism. Besides improving our understanding of biochemical processes, metabolomics is used for environmental monitoring, natural product discovery, or even chemotaxonomy, among others. However, for marine macroalgae, comparative large-scale metabolomics studies are lacking, even though seaweeds belong to the most important aquatic primary producers. In this study, we present via a broad scale systematic metabolomics survey 391 metabolites from 21 seaweeds species, representing brown, red and green algae. We demonstrate clear differences in metabolite composition of these seaweeds, reflecting their taxonomic classification. We highlight these differences for amino acid, amino acid derivative and peptide metabolites, energy and carbohydrate metabolites, for lipid, fatty acid and sterol metabolites and for secondary metabolites, including selected metabolic pathways such as the urea cycle, the citrate cycle and the glyconeogenesis/glycolysis, besides others. Additionally, we link selected seaweed biochemical properties to potential pharmaceutical and nutraceutical applications.

Til dokument

Sammendrag

The extractive content of inner and outer heartwood of nine Scots pine trees from three different stands in Norway was determined by automated solvent extraction and biological screening tests were performed using basidiomycetes. The evaluation of mass spectra by means of a NIST library search shows that in the petroleum ether extracts α-pinene and carene as well as terpinene and cadinene derivatives are the main extractives found in both inner and outer heartwood. In the inner heartwood, however, these substance groups were found in lower quantities. These substances mainly have a hydrophobic effect. The screening tests indicate that also extractive-rich heartwood is extremely degraded by Poria placenta which corresponds to the analytical results of the petroleum ether extracts.