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
Varsling og middelvalg i tørråtebekjempelsen i 2008 blir omtalt
Forfattere
Bent J. Nielsen Jens Grønbech Hansen Hans Pinnschmidt Lars Bødker Ragnhild Nærstad Vinh Hong Le Arne Hermansen Asko HannukalaSammendrag
Influence of weather conditions on sporangia production, release and infection of P. infestans was investigated in Denmark, Norway and Finland using Burkard spore traps and trap plants exposed in field plots. Results from field trials show that P. infestans normally forms its sporangia during humid periods at night and that they are released by a drop in the humidity in the morning. The infection can occur in the morning if there are dew drops remaining on the canopy while sporangia are being released. Sporangia released into the air can only infect if they make contact with free water from either dew or precipitation within very few hours. The studies also showed that the newly formed sporangia can remain in the lesions during overcast weather conditions and be dispersed over at least 2-3 days. By coupling the sporangia formation with a model of sporangia survival as affected by global radiation, a better correlation was achieved between infection on trap plants and dispersed sporangia than if only the index of sporangia formation was used as a predictor. The involvement of the survival model will reduce the number of false warnings, and thus reduce fungicide consumption.
Forfattere
Bent J. Nielsen Jens Grønbech Hansen Hans Pinnschmidt Lars Bødker Ragnhild Nærstad Vinh Hong Le Arne Hermansen Asko HannukalaSammendrag
Influence of weather conditions on sporangia production, release and infection of P. infestans was investigated in Denmark, Norway and Finland using Burkard spore traps and trap plants exposed in field plots. Results from field trials show that P. infestans normally forms its sporangia during humid periods at night and that they are released by a drop in the humidity in the morning. The infection can occur in the morning if there are dew drops remaining on the canopy while sporangia are being released. Sporangia released into the air can only infect if they make contact with free water from either dew or precipitation within very few hours. The studies also showed that the newly formed sporangia can remain in the lesions during overcast weather conditions and be dispersed over at least 2-3 days. By coupling the sporangia formation with a model of sporangia survival as affected by global radiation, a better correlation was achieved between infection on trap plants and dispersed sporangia than if only the index of sporangia formation was used as a predictor. The involvement of the survival model will reduce the number of false warnings, and thus reduce fungicide consumption.
Forfattere
Bent Nielsen Jens G. Hansen Hans Pinnscmidt Ragnhild Nærstad Arne Hermansen Vinh Hong Le Asko Hannukkala Lars BødkerSammendrag
Release and infectivity of Phytophthota infestans sporangia under field conditions
Forfattere
Arne HermansenSammendrag
Skurv i potet: Påvirkes skurv av vekstavslutning? Informasjon om nytt skurvprosjekt fra 2008
Forfattere
Arne HermansenSammendrag
Soppsjukdommer i løk. Sprøytestrategi i 2008
Forfattere
Bent J. Nielsen Jens Grønbech Hansen Hans Pinnschmidt Ragnhild Nærstad Arne Hermansen Vinh Hong Le Asko HannukkalaSammendrag
The existing potato late blight forecast and decision support systems used in the Nordic countries are based on data from the 1930s and the 1950-60s on how temperature and humidity influence Phytophthora infestans epidemiology. Influence of weather conditions on sporangium production, release, viability and infection of P. infestans was investigated in Denmark, Norway and Finland using Burkard spore traps and exposure of trap plants in field plots in 2005-2007. Large amounts of sporangia were trapped after nights with long periods with high humidity. Sporangia produced in one humidity period were mainly released at the first humidity drop in the morning hours, but there were also some periods with delayed sporangium release. Local new infections occurred mainly during the morning hours when leaves were still wet. On many days sporangia did not survive until the afternoon and the results indicate that conditions for survival of sporangia and infection are major bottlenecks for the spread and development of the disease. These results have important implications for practice. Survival of sporangia and infection must be better integrated into the calculation of "risky days" in late blight forecasting systems.
Forfattere
Ragnhild Nærstad Arne Hermansen Vinh Hong Le Bent J. Nielsen Jens Grønbech Hansen Hans Pinnschmidt Asko HannukkalaSammendrag
The existing potato late blight forecast and decision support systems used in the Nordic countries are based on data from the 1930s and the 1950-60s on how temperature and humidity influence Phytophthora infestans epidemiology. Influence of weather conditions on sporangium production, release, viability and infection of P. infestans was investigated in Denmark, Norway and Finland using Burkard spore traps and exposure of trap plants in field plots in 2005-2007. Large amounts of sporangia were trapped after nights with long periods with high humidity. Sporangia produced in one humidity period were mainly released at the first humidity drop in the morning hours, but there were also some periods with delayed sporangium release. Local new infections occurred mainly during the morning hours when leaves were still wet. On many days sporangia did not survive until the afternoon and the results indicate that conditions for survival of sporangia and infection are major bottlenecks for the spread and development of the disease. These results have important implications for practice. Survival of sporangia and infection must be better integrated into the calculation of "risky days" in late blight forecasting systems.
Forfattere
Arne HermansenSammendrag
Svartskurv kan også gi vekstsprekk i potet
Forfattere
Arne HermansenSammendrag
Tuber diseases in potatoes