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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.

2025

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Sammendrag

Key message Multiple QTLs for powdery mildew resistance were identifed in a pre-breeding population derived from the octoploid progenitor species of garden strawberry, including a stable major novel factor on chromosome 3B. Abstract Powdery mildew (PM), caused by the biotrophic fungal pathogen Podosphaera aphanis, poses an increasing threat to garden strawberry (Fragaria×ananassa) production worldwide. While a few commercial cultivars exhibit partial resistance, fungicide application remains essential for managing PM outbreaks. However, breeding ofers a more sustainable approach for controlling PM. A better understanding of the genetics of resistance is required for informed breeding strategies, e.g. through identifying novel resistance factors derived from the progenitor species of garden strawberry, F. chiloensis and F. virginiana. We conducted genome-wide association (GWA) and multivariate analyses in a reconstructed (ReC) strawberry population to investigate PM resistance under natural infection. Leveraging multi-year feld trial data and 20,779 singlenucleotide polymorphism markers, we identifed a novel major quantitative trait locus (QTL) on chromosome 3B, designated as q.LPM.Rec-3B.2, that was consistently associated with high PM resistance in both leaves and fruits. Greenhouse validation with a subset of the ReC population confrmed that this QTL region was stable across feld and greenhouse environments. Promising candidate genes for resistance, including two for MLO and one for EXO70, were identifed within this major QTL. In addition, multi-locus GWA models and non-additive GWA revealed additional resistance QTLs on multiple chromosomes. Despite previous challenges in breeding for robust PM resistance due to its quantitative nature and complex genetic control, our results provide valuable insights into resistance-contributing QTL regions already existing in strawberry, novel wildderived resistance QTLs not previously known, candidate genes, and pre-breeding germplasm carrying resistance traits as resources for future genome-informed breeding eforts.

Sammendrag

In this chapter, we outline what is known about climatic and stress memory in trees, with examples covering different groups and species of trees (conifers, poplar, oak, ash, and eucalypts). We focus on two broad types of memory: (1) immune memory involved in inducible defenses (defense priming) and (2) climatic memory, whereby trees maintain certain phenological phenotypes in response to environmental conditions experienced during embryogenesis. We outline the epigenetic mechanisms that are thought to be involved in the creation and maintenance of climatic and stress memory in trees. We also give examples of how to study such memories in trees. In these examples, we focus on research protocols that have been proven useful to characterize memories and their mechanistic basis, with an emphasis on molecular techniques that can be used to dissect epigenetic mechanisms.