NIBIO
Frederik A. Dahls vei 20,
1430 ÅS

Sentralbord: 03 246
(Man-fre frå kl 0800 - 1530)

Ansvarleg redaktør:
Ragnar Våga Pedersen

Nettredaktør:
Morten Günther

Redigere nettsiden

NIBIO har ikkje ansvar for innhald på eksterne nettsider som det er lenka til.

Tittel: Inoculum sources for downy mildews in onion, lettuce and cucumber in Norway
Kommentar: ICPP 2008. 9th International Congress of Plant Pathology. Torino, Italy. 24-29. august 2008
Forfattere:Nordskog, B., Gadoury, D., Brurberg, M., Sivertsen, T., Kennedy, R. & Hermansen, A.
Navn på utgivelse: Poster
Publikasjonstype: Poster
Utgivelsesår: 2008
Avdeling: Bioforsk Plantehelse - Ås
Fagområde: Plantehelse og plantevern
Sammendrag: Downy mildews represent some of the most important plant diseases in the production of several field vegetable crops in Norway. Disease outbreaks are difficult to predict since severity of the diseases and the first appearance of the pathogens can differ substantially between seasons. As part of an ongoing project, the initial sources of inoculum for downy mildews of onion (Peronospora destructor), lettuce (Bremia lactucae) and cucumber (Pseudoperonospora cubensis) is investigated to ensure the use of appropriate control measures for these diseases in Norway. Necrotic leaf tissue from infected plants has been examined for the presence of oospores. Oospores have so far been found profusely in lettuce and sparsely in onion, but not in cucumber. Other aspects that are surveyed are the distribution of spores in air. Spore traps are used to identify both the initial appearance of inoculum, and the presence and amount of spores over a field. To determine spore quantities, real-time PCR has been applied to analyze daily spore catch. These results were compared to data from parallel spore traps where hourly numbers of spores are enumerated by use of microscope. An attempt to backtrack an early infection of P. cubensis was made by producing trajectories to show where possible sources of infection may be located in the case of long distance distribution of spores by air. This work will be continued in 2008 and 2009, and the results will be used for better forecasting of downy mildew pathogens in Norway.
a a a