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
Forfattere
Arne Stensvand David M. Gadoury Håvard Eikemo Andrew Dobson M. Catherine Heidenreich Robert C. SeemSammendrag
Field trials at Ås, Norway and Geneva, NY, USA revealed a substantial impact of initial levels of powdery mildew (Podosphaera macularis) upon disease development in strawberry (Fragaria × ananassa). Five-row plots of 50 to 100 mildew-free plants (planting distance 0.45 × 1.2 m) were established each year within large grain fields with a minimum distance of 90 m between plots and were left untreated with fungicides. Beginning each season, plants at the center of each plot were inoculated with 0, 1, 10, or 100 mildew-infected leaflets. Uninoculated plots developed only trace levels of powdery mildew, despite nearby diseased plots and wild strawberries in both Norway and NY trials over 3 years. More rapid and severe disease development was observed in the inoculated plots; e.g., mildew was observed on 31, 36, 311, and 912 leaflets in the 0, 1, 10, and 100 plots, respectively, in Norway in year 1 of the trial, and reached only 6 leaves per plot in the 0 plot in year 2. Spatiotemporal analyses were subsequently performed, but the practical impact of the trials was to demonstrate long-lasting benefits of clean, mildew-free planting stock in commercial strawberry production, even in areas where the pathogen is endemic and the environment is very conducive to disease.
Forfattere
Robert C. Seem Arne Stensvand David M. Gadoury Håvard Eikemo Andrew Dobson M. Catherine HeidenreichSammendrag
The objective of this work was to investigate how primary disease levels of powdery mildew (Podosphaera aphanis) in strawberry (Fragaria × ananassa) influence disease development in time and space. Experiments were repeated over two seasons in field trials in Norway (Ås, cv. Korona) and USA (Geneva, NewYork, cvs. Earliglow and Elan). Five-row plots of 50 to 100 mildew-free plants (planting distance 0.45 x 1.2 m) were established each year within large grain fields, with a minimum distance of 90 m between plots, and no fungicide treatments. At start of the experiments, plants at the center of each plot were inoculated with 0, 1, 10, or 100 mildew-infected leaflets. Uninoculated plots developed only trace levels of powdery mildew, despite nearby diseased plots. More rapid and severe disease development was observed in the inoculated plots; e.g., mildew was observed on 31, 36, 311, and 912 leaflets in the 0, 1, 10, and 100 plots, respectively, in Norway in year 1 of the trial. Within the plots, disease development was highest close to the inoculum source and downwind from the prevailing wind. It may be concluded that in the absence of nearby sources of contamination, disease severity in strawberry plantings is determined by the dose of initial inoculum resident within the planting. The practical impact of the trials was to demonstrate long-lasting benefits of clean, mildew-free planting stock in commercial strawberry production, even in areas where the pathogen is endemic and the environment is very conducive to disease.
Forfattere
Belachew Asalf Tadesse Arne Stensvand David M. Gadoury Robert C Seem Andrew Dobson Anne-Marte TronsmoSammendrag
Development of ontogenic resistance to powdery mildew (Podosphaera aphanis) in strawberry fruit has not been quantified, and thus cannot be exploited in disease management programs. Four commercially-relevant strawberry cultivars were evaluated for ontogenic resistance to powdery mildew. Fruits were inoculated at one of the four growth stages: flowering, green, white and early pink fruit. There was a significant difference between and within cultivars at the bloom and green stage of inoculations (P <0.05) for both disease incidence and severity. On average 16.4, 39.5, 48.7, and 60.3 % of the fruits inoculated at bloom developed powdery mildew in cultivars Elan, Korona, Frida and Inga, respectively. None of the cultivars developed powdery mildew when inoculated at the pink stage. It may be concluded that flowers and green fruits of strawberry were much more susceptible to powdery mildew infection than white and pink fruits. The high susceptibility of cultivars at the flower and early green stages seemed coincident with the succulent nature of the fruits at these stages, making it easy for penetration and establishment of mildew. Control measures targeting at these critical windows of fruit susceptibility are likely to reduce yield loss.
Forfattere
Belachew Asalf Tadesse Arne Stensvand David M. Gadoury Robert C Seem Andrew Dobson Anne-Marte TronsmoSammendrag
Det er ikke registrert sammendrag
Sammendrag
De senere årene er det registrert økt forekomst av sopparten Fusarium graminearum i norskprodusert korn. F. graminearum produserer blant annet soppgiften deoksynivalenol (DON). Korn høstet fra angrepne planter kan derfor være uegnet til mat og fôr.
Sammendrag
Aksfusariose er en utbredt og destruktiv sjukdom i korn. Korn høsta fra angrepne planter kan inneholde soppgifter (mykotoksiner) og derfor være uegnet til mat og fôr. I Fusariumprosjektet ved Bioforsk Plantehelse ønsker vi å kartlegge faktorer som kan ha betydning for angrep av aksfusariose og utvikling av mykotoksiner i kornet.
Sammendrag
Behandling med Proline under blomstring reduserte mengden deoksynivalenol (DON) med 40-80 %. Derimot var det ingen reduksjon ved fungicidbehandling av de svært giftige toksinene T-2 og HT-2.
Sammendrag
For å kunne imøtekomma EU sine krav (som er handheva av Mattilsynet) om å redusera innhaldet av mykotoksin i korn som går til mat og for, jobbar vi på ’Fusariumprosjektet’ på Bioforsk med å etablere ein strategi for identifisering av kontaminerte kornprøver. Denne strategien går blant anna ut på å etablere ei metode for hurtigtesting av eit større antal prøver.
Sammendrag
I felt finnes en rekke ulike Fusarium-arter som kan forårsake aksfusariose. Disse artene påvirker hverandre i et komplisert samspill. Dette samspillet har betydning for sykdomsutviklingen hos den enkelte kornart, og vil influere på veksten av den enkelte Fusarium-art og på mengden av de ulike mykotoksinene som blir produsert.
Sammendrag
Vi har laget varslingsmodeller for DON-innhold i hvete, men modellene må testes i praksis slik at vi kan fastslå påliteligheten. Feltdata som jordarbeiding og vekstskifte må også inkluderes i modellene for at de skal bli sikrere.