Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2021
Abstract
No abstract has been registered
Authors
Diego Abalos Tatiana Francischinelli Rittl Sylvie Recous Pascal Thiébeau Cairistiona F. E. Topp Kees Jan van Groenigen Klaus Butterbach-Bahl Rachel E. Thorman Kate E. Smith Ishita Ahuja Jørgen E. Olesen Marina Azzaroli Bleken Robert M. Rees Sissel HansenAbstract
Crop residue incorporation is a common practice to increase or restore organic matter stocks in agricultural soils. However, this practice often increases emissions of the powerful greenhouse gas nitrous oxide (N2O). Previous meta-analyses have linked various biochemical properties of crop residues to N2O emissions, but the relationships between these properties have been overlooked, hampering our ability to predict N2O emissions from specific residues. Here we combine comprehensive databases for N2O emissions from crop residues and crop residue biochemical characteristics with a random-meta-forest approach, to develop a predictive framework of crop residue effects on N2O emissions. On average, crop residue incorporation increased soil N2O emissions by 43% compared to residue removal, however crop residues led to both increases and reductions in N2O emissions. Crop residue effects on N2O emissions were best predicted by easily degradable fractions (i.e. water soluble carbon, soluble Van Soest fraction (NDS)), structural fractions and N returned with crop residues. The relationship between these biochemical properties and N2O emissions differed widely in terms of form and direction. However, due to the strong correlations among these properties, we were able to develop a simplified classification for crop residues based on the stage of physiological maturity of the plant at which the residue was generated. This maturity criteria provided the most robust and yet simple approach to categorize crop residues according to their potential to regulate N2O emissions. Immature residues (high water soluble carbon, soluble NDS and total N concentration, low relative cellulose, hemicellulose, lignin fractions, and low C:N ratio) strongly stimulated N2O emissions, whereas mature residues with opposite characteristics had marginal effects on N2O. The most important crop types belonging to the immature residue group – cover crops, grasslands and vegetables – are important for the delivery of multiple ecosystem services. Thus, these residues should be managed properly to avoid their potentially high N2O emissions.
Authors
Ishita AhujaAbstract
No abstract has been registered
Authors
Ishita AhujaAbstract
No abstract has been registered
Authors
Mari Mette TollefsrudAbstract
No abstract has been registered
Authors
Tor MykingAbstract
No abstract has been registered
Authors
Arne SteffenremAbstract
No abstract has been registered
Authors
Inger Sundheim FløistadAbstract
No abstract has been registered
Authors
Tore SkrøppaAbstract
Denne rapporten presenterer resultater fra forsøk med populasjoner fra Sør-Norge og Trøndelag og med provenienser fra Mellom-Europa og Finland. Både korttidsforsøk plantet på jordbruksmark og feltforsøk i skogen ble plantet. Målinger og registreringer ble gjort av høyde, tidlighet og høstskudd. Det var signifikante forskjeller i disse egenskapene både mellom provenienser, norske populasjoner og familier innen populasjoner. For de norske populasjonene var det samspill for middeltall av høyde og tidlighet i korttids- og feltforsøkene. Betydelige samspill for overlevelse og høyde ble funnet mellom provenienser og lokaliteter for feltforsøk som bare ligger noen få kilometer fra hverandre. Disse samspillene kom sannsynligvis på grunn av forskjeller i det lokale temperaturklimaet. Kunnskap om samspill og om de avhenger av geografiske og klimatiske faktorer, er viktig både for valg av provenienser og for planteforedlingen for gran.
Abstract
Methyl jasmonate (MeJA) treatment elicits induced resistance (IR) against pests and diseases in Norway spruce (Picea abies). We recently demonstrated using mRNA-seq that this MeJA-IR is associated with both a prolonged upregulation of inducible defenses and defense priming. Gene expression can be regulated at both a transcrip-tional and post-transcriptional level by small RNAs, including microRNAs (miRNAs). Here we explore the effects of MeJA treatment and subsequent challenge by wounding on the Norway spruce miRNA transcriptome. We found clusters of prolonged down- or upregulated miRNAs as well as miRNAs whose expression was primed after MeJA treatment and subsequent wounding challenge. Differentially expressed miRNAs included miR160, miR167, miR172, miR319, and the miR482/2118 superfamily. The most prominent mRNA targets predicted to be differentially expressed by miRNA activity belonged to the nucleotide-binding site leucine-rich repeat (NBS- LRR) family. Among other predicted miRNA targets were genes regulating jasmonic acid biosynthesis. Our re-sults indicate that miRNAs have an important role in the regulation of MeJA-IR in Norway spruce.