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.
2023
Forfattere
Heidi Udnes Aamot Hesam Mousavi Jafar Razzaghian Guro Brodal Michael Sulyok Rudolf Krska Simon G. Edwards Ingerd Skow HofgaardSammendrag
In Norway, high levels of mycotoxins are occasionally observed in oat grain lots, and this cause problems for growers, livestock producers and the food and feed industries. Mycotoxins of primary concern are deoxynivalenol (DON) produced by Fusarium graminearum and HT2- and T2-toxins (HT2+T2) produced by Fusarium langsethiae. Although effort has been made to understand the epidemiology of F. langsethiae in oats, this is still not fully understood. In the present study, we aimed to increase our understanding of the F. langsethiae – oat interaction. Resistance to F. langsethiae was studied in three oat varieties after inoculation at early (booting, heading, flowering) or late (flowering, milk, dough) growth stages in greenhouse experiments. The oat varieties had previously shown different levels of resistance to F. graminearum: Odal, Vinger (both moderately resistant), and Belinda (susceptible). The levels of F. langsethiae DNA and HT2+T2 in harvested grain were measured, and differences in aggressiveness (measured as the level of F. langsethiae DNA in grain) between F. langsethiae isolates were observed. Substantial levels of F. langsethiae DNA and HT2+T2 were detected in grain harvested from oats that had been spray-inoculated at heading or later growth stages, suggesting that oats are susceptible to F. langsethiae from heading and onwards. Vinger had a moderate resistance to F. langsethiae/HT2+T2, whereas Odal and Belinda were relatively susceptible. We observed that late inoculations resulted in relatively higher levels of trichothecene A metabolites other than HT2+T2 (mostly glycosylated HT-2, and smaller amounts of some other metabolites) in harvested grain, which indicate that infections close to harvest may pose a further risk to food and feed safety.
Sammendrag
I denne rapporten presenteres resultater fra biologisk veiledningsprøving av ugrasmidler; mot ugras i golfgras, mot ugras i vårkorn inkl. testing av VIPS-Ugras, mot fangvekster og ugras i utendørs småskalaforsøk, mot ugras i potet under plast/fiberduk, til nedvisning av potetris, mot søtvierarter uten kultur, mot ugras og jordbærutløpere i jordbær og mot ugras i eple, samt ulike strategier mot ugras i gulrot og rotpersille.
Sammendrag
Det er utført forsøk med soppmidler i bygg, løk, gulrot og eple. I bygg er det testet ulike varslingsmodeller i VIPS mot byggbrunflekk. I løk er det testet ulike beisemidler for å forebygge soppsjukdommer og sikre god løkkvalitet fra starten. I gulrot er det utført forsøk mot gropflekk og ulike lager- og bladflekksjukdommer både i felt og på lager. I eple er det gjort forsøk for å finne nye midler mot lagersjukdommer.
Forfattere
Chatchai Kosawang Isabella Børja Maria-Luz Herrero Nina Elisabeth Nagy Lene R. Nielsen Halvor Solheim Volkmar Timmermann Ari HietalaSammendrag
Introduction: The ascomycete Hymenoscyphus fraxineus, originating from Asia, is currently threatening common ash (Fraxinus excelsior) in Europe, massive ascospore production from the saprotrophic phase being a key determinant of its invasiveness. Methods: To consider whether fungal diversity and succession in decomposing leaf litter are affected by this invader, we used ITS-1 metabarcoding to profile changes in fungal community composition during overwintering. The subjected ash leaf petioles, collected from a diseased forest and a healthy ash stand hosting the harmless ash endophyte Hymenoscyphus albidus, were incubated in the forest floor of the diseased stand between October 2017 and June 2018 and harvested at 2–3-month intervals. Results: Total fungal DNA level showed a 3-fold increase during overwintering as estimated by FungiQuant qPCR. Petioles from the healthy site showed pronounced changes during overwintering; ascomycetes of the class Dothideomycetes were predominant after leaf shed, but the basidiomycete genus Mycena (class Agaricomycetes) became predominant by April, whereas H. albidus showed low prevalence. Petioles from the diseased site showed little change during overwintering; H. fraxineus was predominant, while Mycena spp. showed increased read proportion by June. Discussion: The low species richness and evenness in petioles from the diseased site in comparison to petioles from the healthy site were obviously related to tremendous infection pressure of H. fraxineus in diseased forests. Changes in leaf litter quality, owing to accumulation of host defense phenolics in the pathogen challenged leaves, and strong saprophytic competence of H. fraxineus are other factors that probably influence fungal succession. For additional comparison, we examined fungal community structure in petioles collected in the healthy stand in August 2013 and showing H. albidus ascomata. This species was similarly predominant in these petioles as H. fraxineus was in petioles from the diseased site, suggesting that both fungi have similar suppressive effects on fungal richness in petiole/rachis segments they have secured for completion of their life cycle. However, the ability of H. fraxineus to secure the entire leaf nerve system in diseased forests, in opposite to H. albidus, impacts the general diversity and successional trajectory of fungi in decomposing ash petioles.
Forfattere
Randi Bolli Ingunn H. Gudmundsdottir Monsås Maren Kolltveit Bakkebø Roman Florinski Kari StuvesethSammendrag
Det er ikke registrert sammendrag
Sammendrag
Purpose of Review Forestry in northern temperate and boreal regions relies heavily on conifers. Rapid climate change and associated increases in adverse growing conditions predispose conifers to pathogens and pests. The much longer generation time and presumably, therefore, lower adaptive capacity of conifers relative to their native or non-native biotic stressors may have devastating consequences. We provide an updated overview of conifer defences underlying pathogen and pest resistance and discuss how defence traits can be used in tree breeding and forest management to improve resistance. Recent Findings Breeding of more resilient and stress-resistant trees will benefit from new genomic tools, such as genotyping arrays with increased genomic coverage, which will aid in genomic and relationship-based selection strategies. However, to successfully increase the resilience of conifer forests, improved genetic materials from breeding programs must be combined with more flexible and site-specific adaptive forest management. Summary Successful breeding programs to improve conifer resistance to pathogens and pests provide hope as well as valuable lessons: with a coordinated and sustained effort, increased resistance can be achieved. However, mechanisms underlying resistance against one stressor, even if involving many genes, may not provide any protection against other sympatric stressors. To maintain the adaptive capacity of conifer forests, it is important to keep high genetic diversity in the tree breeding programs. Choosing forest management options that include diversification of tree-species and forest structure and are coupled with the use of genetically improved plants and assisted migration is a proactive measure to increase forest resistance and resilience to foreseen and unanticipated biotic stressors in a changing climate.
Forfattere
Jorunn Børve Lisa Karine Haugland Andrea Podavkova Venche Talgø Morten Wennerberg Arne StensvandSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Joyce Machado Nunes Romeiro Jostein Gohli Paal Krokene Tron Haakon Eid Clara Antón FernándezSammendrag
Bark beetle (Ips typographus) outbreaks have the potential to damage large areas of spruce-dominated forests in Scandinavia. To define forest management strategies that will minimize the risk of bark beetle attacks, we need robust models that link forest structure and composition to the risk and potential damage of bark beetle attacks. Since data on bark beetle infestation rates and corresponding damages does not exist in Norway, we implement a previously published meta-model for estimating I. typographus damage probability and intensity. Using both current and projected climatic conditions we used the model to estimate damage inflicted by I. typographus in Norwegian spruce stands. The model produces feasible results for most of Norway’s climate and forest conditions, but a revised model tailored to Norway should be fitted to a dataset that includes older stands and lower temperatures. Based on current climate and forest conditions, the model predicts that approximately nine percent of productive forests within Norway’s main spruce-growing region will experience a loss ranging from 1.7 to 11 m3/ha of spruce over a span of five years. However, climate change is predicted to exacerbate the annual damage caused by I. typographus, potentially leading to a doubling of its detrimental effects.
Sammendrag
Prosjektet er finansiert av Mattilsynet og arbeidet er utført av Norsk institutt for bioøkonomi (NIBIO). Prosjektets hovedfunksjon er et beredskapslager av feller og luktstoffer som kan benyttes for overvåking ved introduksjon av skadeinsekter i skog. I hovedsak fokuserer prosjektet på Anoplophora- og Agrilus-arter, men andre skadeinsekter inkludert på EPPOs liste over karanteneskadegjørere er også inkludert. I 2022, ved hjelp av fangstmetodikk som ble etablert i 2021, ble fangsteffektiviteten til fire attraktanter testet ved to lokaliteter. Ingen karanteneskadegjørere ble fanget.