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.
2009
Sammendrag
Geoffrey D. Gooch and Per Stålnacke. 2009. THE LAKE PEIPSI AND ITS DRAINAGE BASIN CASE STUDY IWA Publishing. In: Water Framework Directive: Model supported Implementation A Water Manager"s Guide. Edited by Fred F Hattermann and Zbigniew W Kundzewicz. ISBN: 9781843392736. Published by IWA Publishing, London, UK.pp. 184-201
Sammendrag
Mite damage is often considered a spray induced problem. We monitored 12 Norwegian strawberry fields, 6 organic and 6 conventional fields, by sampling leaves two times per year for two years. Young folded leaflets were visually inspected for eggs and adults of strawberry mite (Phytonemus pallidus) and completely unfolded leaves were used for extraction of mobile stages of two-spotted spider mite (Tetranychys urticae). The spider mites were examined for infection of the mite-pathogenic fungus Neozygites floridana. Predatory mites (Phytoseiidae) were recorded on both leaf types, and the females mounted and identified. We also sampled leaves from selected plants in the boundary vegetation of most fields, to look for sources of T. urticae, phytoseiids and N. floridana, and soil from each field, to study the natural occurrence of entomopathogenic nematodes. We will present the results on abundance and diversity of the organisms investigated, and discuss similarities and differences between organic and conventional fields.
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Forfattere
Carl Gunnar Fossdal Nadeem Yaqoob Halvor SolheimSammendrag
The root-rot causing fungus Heterobasidion annosum senso lato is the most devastating pathogen of conifers in Europe. This pathogen enter Norway spruce trees trough the roots and colonizes the tree from within, growing as a saprophyte when established within the dead heartwood and acting as a necrotroph when in contact with living host tissue. The genome of this devastating pathogen has now been sequenced in collaboration with JGI and gene annotation is ongoing and genomic work is currently in progress (Stenlid et al. work in progress). We have worked with the host Norway spruce from a molecular perspective for more than ten years. Twenty percent of the trees in Norwegian spruce stands tend to be infected and this pathogen that can colonize ten meters up inside the trunk. The tree have defences against this pathogen and the attack can be fought off by the bark and living wood but not by the hearthwood. The tree has a unique defense against this internal attack by forming a reaction zone; in this case the host defense is directed inwardly by the still living sapwood toward the central colonized wood. We have in the last years studied the host responses to infection in Norway spruce clones at the transcriptional level and found that the speed of recognition and spatial defense signalling appears to be the hallmarks of trees with high degree of resistance. We strive to study both partners in this pathosystem from a molecular perspective, and are using suppressive subtractive hybridization (SSH) followed by Real-Time RT PCR verification to look at differentially expressed genes(Yakovlev et al. 2008). In addition the colonization profiles are followed on extracted gDNA using quantitative Real-Time PCR (Hietala et al. 2009).
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Forfattere
Björn Andersson A-K Widmark J E Yuen G J T Kessel B Evenhuis L J Turkensteen A Lehtinen B Nielsen S Ravnskog J G Hansen Arne Hermansen May Bente Brurberg Berit NordskogSammendrag
Det er ikke registrert sammendrag
Sammendrag
The summary of the main findings from the ongoing EU-project STRIVER (2006-2009) will be presented based on experiences from the four case basins: Glomma (Norway), Tagus (Spania and Portugal), Tungabhadra (India) and Sesan (Vietnam and Cambodia) focusing on integrated water resources management.
Sammendrag
Members of the APSES family of fungal proteins have been identified as key regulators of fungal development, controlling processes such as mating, sporulation and dimorphic growth. We deleted the FgStuA gene in Fusarium graminearum and show that the mutant is greatly impaired in spore development, pathogenicity and secondary metabolism. FgStuA is closely related to FoStuA in F. oxysporum, but unlike FoStuA mutants the FgStuA mutants were greatly reduced in pathogenicity both on wheat and apple slices. The lack of ability to cause disease on wheat heads may be due to lack of trichothecene accumulation in planta. The FgStuA mutant also had a white/yellow mycelial phenotype compared to the red pigmented (aurofusarin) wild-type, had reduced aerial mycelium, susceptibility to oxidative stress, and had a less hydrophobic surface. Microarray analysis showed that most phenotypes could be inferred from gene expression data, such as down-regulation of the trichothecene gene cluster in the mutant. In an attempt to separate primary and secondary effects of FgStuA deletion, we carefully examined gene expression data together with promoter analysis and comparative genomics. The genes flanking FgStuA are conserved and syntenous in other fungal genomes and contain a gene encoding a putative clock controlled protein. FgStuAp and other APSES proteins share significant homology with DNA-binding domains of transcription factors controlling the critical G1/S phase cell cycle transition in both S. cerevisiae and S. pombe. Genes within MIPS Functional Category (FunCat) 10 "Cell cycle and DNA processing" are enriched among those more highly expressed in the FgStuA mutant than wild-type. Aspergillus StuAp response elements (A/TCGCGT/ANA/C) also were found highly enriched in promoter sequences for FunCat 10 genes, compared to the genome as a whole. Our results suggests that FgStuAp may act primarily as a repressor involved in cell cycle regulation, and may act only secondarily on sporulation, pathogenicity, and secondary metabolism.