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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.

2006

Sammendrag

A survey of the loose smut frequencies in certified barley seed lots in Norway during 1997"2002 showed that the disease has become more prevalent and has occurred at higher infection frequencies in recent years. Laboratory analyses (embryo method) of barley seeds harvested in 2001 and 2002, including both certified and farm saved seed, showed a large number of infected seed lots with higher than expected infection frequencies. One lot of farm saved seed (cv. Otira) from 2002 had 32% seed infection. Unexpectedly high loose smut infection frequencies recorded in fields sown with carboxin treated barley seed suggest a reduced effectiveness of the fungicide. A seed treatment experiment was conducted in 2002 using both greenhouse and field trials with two infected seed lots (cv. Otira with 14.4% and cv. Fager with 6.9% infected seeds) to evaluate and compare the effect of Fungazil C (carboxin + imazalil) and Premis Robust (triticonazol + imazalil) against loose smut. Fungazil C at normal rates reduced loose smut frequencies by approximately 50% or less. At twice the normal rate, loose smut symptoms were reduced by 60-80%. Premis Robust showed more effective loose smut control, but did not confer complete control.

Sammendrag

Increasing levels of Fusarium mycotoxins have been recorded in Norwegian cereals during the last few years. In 2004, unusual high levels of deoxynivalenol (DON) were recorded, in particular in oats (e.g. 25-30 000 ppb) and some alarming levels of T-2 and HT-2 were recorded in 2005, also in oats. Due to the lack of effective control measures, FHB and mycotoxin contamination poses a significant threat to the yield and quality of cereals. Today only a very limited number of check samples of grains used for food and fodder are tested for mycotoxin content. To reduce the risk of contaminated cereals entering the food and feed processing chain, a four-year project (2006-2009) has been started, with the aim to develop a strategy for identification and discarding of unsuitable grain lots. Because there will be impracticable to analyse every lot the basis for a three-step screening system will be established: 1 - Development of prediction models based on information about effects of agronomic/cultivation practice and climatic conditions, for selection of putative `high-risk" fields/lots; 2 " Selection of a suitable and rapid testing method with capacity to screen a large number of samples for relevant mycotoxins at low costs, for testing of `high-risk" lots; 3 " Chemical toxin analyses of grain lots found to be highly contaminated in step 2. Fusarium avenaceum , F. culmorum, F. poae and F. tricinctum have been the most frequently recorded Fusarium species on cereals in Norway for many years. However, more recently also F. graminearum has occurred more frequently and F. langsethia has been detected especially in oats. Investigations will be carried out to see if there has been a change in the composition of Fusarium species.

Sammendrag

To avoid problems with seed borne diseases in organic cereal production, seed health testing should be compulsory in certification of organic seed. In general, significantly lower infection frequencies of seed borne diseases are recorded on seedlings than on seed. Thresholds for the amount of seed borne inoculum that can be accepted for organic production are therefore needed. The aim of the work presented is to compare transmission rates of Drechslera on barley and oats under organic and conventional conditions, to be able to decide if existing thresholds used to assess the need of chemical seed treatment, can be applied for acceptance of organic seed lots, or for recommendation of alternative treatments. Field experiments were carried out in 2005 in conventional and organic fields situated close to each other at each of three locations (south/east-Norway, east-Norway and mid-Norway). 10 seed lots of barley and 10 lots of oats, with a range of seed infections (barley: 0-94 % Drechslera teres, average 23,7 %; oats: 0-66 % Drechslera avenae, average 22,0 %) were planted in rows of 100 seeds with 8 replicates in each location/`growing system". Percent emergence and seedlings with primary infections were recorded at BBCH 12-13. In average of the three locations 2,5 % and 2.1 % barley seedlings were infected when grown in conventional and organic fields, respectively. In oats, 2,0 % and 0,8 % infected seedlings were recorded in conventional and organic fields, respectively. Similar experiments will be carried out in 2006 and results from this will also be presented.