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.
2008
Sammendrag
The Fusarium genus includes devastating plant pathogenic fungi that cause diseases in cereals around the world. They produce several mycotoxins, including the estrogenic compound zearalenone. To better understand the molecular mechanisms determining zearalenone production, we performed differential display RT-PCR under conditions where Fusarium graminearum and F. culmorum produced high amounts of zearalenone. We found 133 expressed sequence tags (ESTs) and 54 of these were considered to be up-regulated during high zearalenone production. Several of the ESTs were confirmed to be up-regulated by real-time qPCR, but none showed any significant down-regulation in the zearalenone negative mutant Delta PKS4-T9, or were similar to typical gene expression patterns of previously described zearalenone-related genes. Some of the up-regulated ESTs were similar to genes involved in secondary metabolite production, lipid metabolism, transcriptional activation, provision of precursors, signal transduction, transport or detoxification. Several of the ESTs were also located adjacent to one another in the genome and therefore might represent genes involved in the same biosynthetic pathway. Members of six such putative pathways could be found. All sequences were compared to the MIPS F. graminearum Genome Database to verify autocalled gene predictions experimentally and to introduce new exons and gene structures.
Sammendrag
We deleted the FgStuA gene in Fusarium graminearum and demonstrate its involvement in spore development, pathogenicity and secondary metabolism. The FgStuA protein is a member of the APSES family which regulate morphogenesis and virulence in ascomycetes. FgStuA is closely related to FoStuA in F. oxysporum and stuA in Aspergillus, but unlike FoStuA mutants, the FgStuA mutants were greatly reduced in pathogenicity on wheat and colonization of apple slices. The mutant produces no detectable trichothecenes on the wheat cultivar Bobwhite, and
Sammendrag
We deleted the FgStuA gene in Fusarium graminearum and demonstrate its involvement in spore development, pathogenicity and secondary metabolism. The FgStuA protein is a member of the APSES family which regulate morphogenesis and virulence in ascomycetes. FgStuA is closely related to FoStuA in F. oxysporum and stuA in Aspergillus, but unlike FoStuA mutants, the FgStuA mutants were greatly reduced in pathogenicity on wheat and colonization of apple slices. The mutant produces no detectable trichothecenes on the wheat cultivar Bobwhite, and
Sammendrag
The filamentous fungus Fusarium graminearum causes extensive losses on cereals world-wide and contaminates harvested grain with mycotoxins, whose levels in the food supply are strictly regulated. We deleted the FgStuA gene in Fusarium graminearum and demonstrate its involvement in several different processes, such as spore development, pathogenicity and secondary metabolism. The FgStuA protein is a members of the APSES family which regulate morphogenesis and virulence in ascomycetes. FgStuA is closely related to FoStuA in F. oxysporum and StuA in Aspergillus, but unlike FoStuA mutants, the FgStuA mutants were greatly reduced in pathogenicity both on wheat and apple slices. Reduced pathogenicity may be due to decreased levels of trichothecene mycotoxins (
Forfattere
Matias Pasquali Erik Lysøe Andrew Breakspear Kyeyong Seong Jon Menke Jin-Rong Xu H. Corby KistlerSammendrag
To understand mycotoxin accumulation and the infection cycle of the wheat head blight pathogen Fusarium graminearum sensu stricto,fungal gene expression profiles were monitored during plant infection. Strains containing mutations in genes for three transcription factors were found to control deoxynivalenol (DON) accumulation in planta and pathogenicity. Expression profiles were compared between wildtype and these mutants during infection of wheat. Mutants deleted for the StuA gene were greatly decreased in sporulation and produced no perithecia in culture. Unlike "stuA mutants in F. oxysporum, F. graminearum "stuA mutants were greatly reduced in pathogenicity. Reduced pathogenicity may be due to decreased DON levels in planta, which in the mutant were
Forfattere
Mathias Pasquali Erik Lysøe Publikasjonsforfatter Keong Seong Jon Menke J. Xu H. Corby KistlerSammendrag
To understand mycotoxin accumulation and the infection cycle of the wheat head blight pathogen Fusarium graminearum sensu stricto,fungal gene expression profiles were monitored during plant infection. Strains containing mutations in genes for three transcription factors were found to control deoxynivalenol (DON) accumulation in planta and pathogenicity. Expression profiles were compared between wildtype and these mutants during infection of wheat. Mutants deleted for the StuA gene were greatly decreased in sporulation and produced no perithecia in culture. Unlike "stuA mutants in F. oxysporum, F. graminearum "stuA mutants were greatly reduced in pathogenicity. Reduced pathogenicity may be due to decreased DON levels in planta, which in the mutant were
Forfattere
I. A. Yakolev Daniel Kwaku Addo Asante Carl Gunnar Fossdal Jouni Partanen Olavi Junttila Øystein JohnsenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Vi studerer to sykdommer forårsaket av Phytophthora, rotstokkråte i jordbær (P. cactorum) og rød rotråte i bringebær (P. fragariae var. rubi (Pfr)). Bringebær og jordbær sorter varierer i resistens, men de fleste kommersielle kultivarene er mottakelige for disse to sykdommene. En universell merkemetode ble brukt for å gjøre markøranalyse for å identifisere genetiske markører koblet til resistens. For bringebær er populasjonen brukt for kartlegging avkommene fra en krysning mellom resistent Asker og mottakelig Glen Moy. Resistensen til 200 avkom har blitt testet under kontrollerte betingelser med smitting i vannkultur. Tretti dager etter inokulering med mycel av Pfr ble grad av symptom registrert. Kommersielt dyrket jordbær er en svært heterozygot oktoploid. Vi bruker derfor diploid villjordbær som en modellplante. Bioforsk har en samling av diploide jordbærgenotyper fra ulike steder i Norge. Totalt har 68 genotyper blitt testet for deres resistens mot P. cactorum. Ulik grad av resistens har blitt observert. Mottakelige så vel som svært resistente aksesjoner har blitt identifisert. Basert på disse resultatene vil genotyper bli valgt for å lage en segregerende populasjon fra en resistent x mottagelig krysning for å studere nedarvingen av P. cactorum resistensen.
Sammendrag
Vi studerer to sykdommer forårsaket av Phytophthora, rotstokkråte i jordbær (P. cactorum) og rød rotråte i bringebær (P. fragariae var. rubi (Pfr)). Bringebær og jordbær sorter varierer i resistens, men de fleste kommersielle kultivarene er mottakelige for disse to sykdommene. En universell merkemetode ble brukt for å gjøre markøranalyse for å identifisere genetiske markører koblet til resistens. For bringebær er populasjonen brukt for kartlegging avkommene fra en krysning mellom resistent Asker og mottakelig Glen Moy. Resistensen til 200 avkom har blitt testet under kontrollerte betingelser med smitting i vannkultur. Tretti dager etter inokulering med mycel av Pfr ble grad av symptom registrert. Kommersielt dyrket jordbær er en svært heterozygot oktoploid. Vi bruker derfor diploid villjordbær som en modellplante. Bioforsk har en samling av diploide jordbærgenotyper fra ulike steder i Norge. Totalt har 68 genotyper blitt testet for deres resistens mot P. cactorum. Ulik grad av resistens har blitt observert. Mottakelige så vel som svært resistente aksesjoner har blitt identifisert. Basert på disse resultatene vil genotyper bli valgt for å lage en segregerende populasjon fra en resistent x mottagelig krysning for å studere nedarvingen av P. cactorum resistensen.
Forfattere
Paal KrokeneSammendrag
Combined bark beetle-fungus attacks are a key factor in conifer ecosystems in the Northern Hemisphere, where they regularly cause massive tree mortality. Central to the success of the bark beetle-fungus complex is the fact that bark beetles are among the few insects that are capable of breaching the potent anatomical and chemical defenses of healthy tree stems.....