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.
2006
Sammendrag
VIPS (Varsling Innen PlanteSkadegjørere) has been developed under a government-funded action for reducing risk connected to the use of pesticides. Inputs to the forecasting models are weather data from the Bioforsk Agrometeorological Service consisting of a network of 80 weather stations, weather forecasts from the Norwegian Meteorological Institute and biological observations from the Norwegian Agricultural Extension Service. The service is open for the public, free of charge at www.vips-landbruk.no. At the moment VIPS includes forecasts for Stagonospora nodorum (glume blotch), Drechslera teres (net/spot blotch), Rhynchosporium secalis (scald), Sclerotinia sclerotiorum in oil seed rape, Phytophthora infestans (potato late blight), Mamestra brassicae (cabbage moth), Delia radicum (cabbage root fly), Psila rosae (carrot root fly), Venturia inequalis (apple scab), Cydia pomonella (apple moth) and Botrytis cinerea in strawberry. Models for additional pests/diseases are under development. During the growing season the occurrence of several pests and diseases are recorded through a message system. VIPS also includes a programme to assess the need for control of weeds in cereal fields (choice of herbicide(s) and calculation of doses). Current development aim at transferring the service from weatherstation-based to farm-based pest forecasts. Use of radar measurements of precipitation in combination with online interpolation of the other weather factors from nearest weather stations is expected to improve precision in the pest forecasts as well as farmers "ownership" to the information presented.
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.
Forfattere
Dag-Ragnar BlystadSammendrag
Friskt, sortsekte utgangsmateriale for formering av vegetativt formerte vekster er et viktig tiltak for å bekjempe virus og bakterier. Enkelte arter av sopp, nematoder og insekter kan også følge plantematerialet, og et friskt formeringsmateriale er en forutsetning for en vellykket bekjempelse. Prosessen for å framstille et slikt materiale kalles fremavl. Fremavl krever samspill mellom brukere, foredlere, FoU-miljøer, kontrollorganer og politiske myndigheter. Et slikt samspill er godt utviklet i Norge og gir sammen med et kjølig klima og god avstand mellom produksjonsenhetene gode muligheter for produksjon av friskt plantemateriale. Artiklen beskriver det norske fremavlssystemet og beskriver eksempler på vellykket bruk og markedsføring av fremavls-materiale av blomster og grøntanleggsplanter.
Sammendrag
The occurrence of Fusarium (represented by Fusarium spp. and Microdochium nivale) has been recorded in barley, oats and spring wheat seeds in Norway since the 1970-ies as part of the seed quality assessment. Annually a large number of samples representing both certified and farm saved seed from all cereal growing areas, was tested (100 or 200 seeds from each sample) at the Seed Testing Laboratory using the freezing blotter, the Doyer filter paper, and/or the agar plate (PDA) methods. In total, almost 30 000 samples of barley, more than 16 000 samples of oats and more than 9 000 samples of spring wheat were tested. The Fusarium frequencies were recorded in each sample, a mean of all samples was calculated each year for each cereal species, and multiple regressions with weather data from the growing season and also the Fusarium incidences in seed the previous year, were carried out. 69 % of the variation of the incidence of Fusarium in barley seeds was explained by 1) precipitation in July, 2) the incidence of Fusarium the previous year (both significant positive effects), and 3) precipitation in June, 4) temperature in July (both significant negative effects). In oat seed, precipitation in July and incidence of Fusarium the previous year explained 59 % of the variation. In spring wheat, as for barley and oats, precipitation in July and the incidence of Fusarium the previous year contributed positively, whereas precipitation in May and temperature in August had a negative effect.These four factors contributed significantly by 58% to the variation of Fusarium in spring wheat seed. It is concluded that the incidence of Fusarium in seed the previous year and precipitation in July were the main factors affecting the incidence of Fusarium in cereal seeds in Norway.
Sammendrag
En ny type blå limfeller med feromoner, Thriplineams, lover mer effektiv fangst av amerikansk blomstertrips i blomster- og grønnsakskulturer i veksthus. Fellene skal være spesielt godt egnet til tripsovervåking om vinteren, da tripsen er mindre aktiv enn om sommeren. Vi testet disse fellene i et gartneri med snittroser under høst- og vinterforhold.
Sammendrag
Rovmidden Amblyseius swirskii er en nykomling på nyttedyrmarkedet i Europa, og anbefales bl.a. i agurk, tomat, paprika, krydderurter, jordbær og diverse prydplanter. Produsenten hevder at A. swirskii etablerer seg lett og oppformerer seg raskt, og at den effektivt bekjemper veksthusmellus, bomullsmellus, nelliktrips og amerikansk blomstertrips. Mattilsynet har nå godkjent Amblyseius swirskii for bruk i norske veksthus fram til 30.06.2012. Vi har prøvd rovmidden mot veksthusmellus og nelliktrips i veksthusagurk, og resultatene tyder på at den kan være et viktig bidrag til bekjempelsen av veksthusmellus og nelliktrips.
Sammendrag
Bekjempelse av veksthusspinnmidd (Tetranychus urticae) og trips med rovmiddene Phytoseiulus persimilis (middrovmidd) og Amblyseius cucumeris (tripsrovmidd) kan være en utfordring i agurk som dyrkes med vekstlys og nedsenkingsmetoden. Mye lys (ca. 200 W/m2) og høy temperatur gjør at klimaet i toppen av plantene ofte blir for tørt til at middrovmidden trives, og mye rovmidd fjernes ved avblading. Artikkelen beskriver de to hovedstrategiene for biologisk bekjempelse av veksthusspinnmidd som brukes i veksthus med agurk, og gir råd om bruk av tripsrovmidd.
Sammendrag
Rovmidden Amblyseius swirskii ble godkjent mot trips og mellus i veksthuskulturer i Norge i juli 2006. Godkjenningen gjelder til 30/6-2012. Selv om A. swirskii bare har vært i salg siden 2005, er det lovende resultater blant annet fra agurk, paprika og snittroser. Det er interessant å prøve rovmidden i kulturer der det er angrep av trips og mellus samtidig og i kulturer med stort smittepress av amerikansk blomstertrips.
Sammendrag
Freezing and thawing influence the transport potential and pathways for contaminants by altering the soil physical properties. Firstly, soil frost delays or impedes infiltration of rain and meltwater, reducing the transport rate of dissolved contaminants. But at the same time, particle bound contaminants may be mobilised because the reduced infiltration capacity increases surface runoff and erosion risk. Secondly, freezing water expands and imposes mechanical stresses on the soil, which may cause aggregate breakdown and facilitate particle detachment and transport. The influence of repeated freezing and thawing on aggregate stability of different soils is poorly documented for Nordic winter conditions. The purpose of this study (Kværnø and Øygarden, subm.) was to quantify the effect of variable freeze-thaw cycles and soil moisture conditions on aggregate stability of three soils: Silt, structured clay loam (Clay A) and artificially levelled silty clay loam (Clay B). These soils are representative of two erosion prone areas in South-eastern Norway. Field moist surface soil was sieved into the fraction 1- 4 mm, and packed into cylinders. The water content of the soil was adjusted, corresponding to matric potentials of -0.75, -2 and -10 kPa. The soil cores were insulated and covered, and subjected to 0, 1, 3 or 6 freeze-thaw cycles: freezing at "15"C for 24 hours, and thawing at 9"C for 48 hours. Aggregate stability was measured in a rainfall simulator (representing rainfall) and a wet-sieving apparatus (representing surface runoff). The aggregate stability of Silt was found to be significantly lower than of Clay A and Clay B. Clay A and Clay B had similar aggregate stabilities, even if it was expected that the artificially levelled Clay B would have lower stability. Freezing and thawing decreased the aggregate stability for all three soils, but the effect was more severe on the silt soil. There was no evident effect of water content on the aggregate stability, probably due to experimental limitations. The wet-sieving apparatus resulted in less aggregate breakdown than the rainfall simulator. Rainfall impact seemed to be more detrimental than wet-sieving the more unstable the soil was, that is, after many freeze-thaw cycles, and on silt soil. The results indicate that freezing and thawing is an important factor influencing the erosion risk of the studied soils. In the future, climate change is expected to give more unstable winters with more freezing and thawing events. Combined with more precipitation as rainfall during the winter period both runoff and erosion will probably increase, possibly resulting in heavier loads of particulate bound contaminants to surface waters. The results are also helpful for improving predictions of contaminant fate and transport, as most of the existing hydrological and soil erosion prediction models do not satisfactorily describe soil processes occurring under Nordic winter conditions. This study focused on arable soils with conventional agricultural management, where plant nutrients and pesticides pose a threat to water quality. It would be useful to conduct similar experiments on soils where other organic and inorganic contaminants are of concern, e.g. on soils where sewage sludge and compost have been applied, and soils in road cuttings and on contruction sites. References Kværnø, S.H. & Øygarden, L. submitted: The influence of freeze-thaw cycles and soil moisture on aggregate stability of three soils in Norway.
Sammendrag
The performances of the plum rootstocks Ferlenain, Ishtara, Jaspi and P 8-13 compared with St. Julien A as a standard, for the cultivars `Opal" and `Reine Claude GF 1119" were assessed in a field trial in western Norway at 60° North. This trial was one part of an international plum rootstock trial located in seven European countries and organized from INRA Bordeaux. Trees were planted in spring 1994; spaced 2.0 x 4.0 m and formed with a central leader as free spindles. Soil management was grass in the alleyways and herbicide strips 1-m wide along the tree rows. Tree vigour, yield, fruit size and yield efficiency were evaluated for the seven subsequent years. Tree size was significantly affected by the rootstocks. P 8-13 produced the largest trees for both cultivars as measured by trunk cross-sectional area. The smallest trees were produced on Ferlenain for the cultivar `Opal" and on Jaspi for `Reine Claude". The cultivar `Opal" was the most productive and gave three times larger crop than "Reine Claude" on average for the six cropping years. The `Reine Claude" trees came two years later into production than `Opal". There were small differences between the different rootstocks in productivity: However, the rootstock Ferlenain produced significant lower crop than the other rootstock for `Opal". Trees on Jaspi were the most yield efficient for `Opal" and Ferlenain for `Reine Claude". The fruit sizes were in general medium to small for both cultivars and became little affected by the different rootstocks. The average fruit size was about 30 g for `Opal" and 25 g for `Reine Claude". Fruit quality characterized by the content of soluble solids was high for `Reine Claude" with average 20 % and 15 % for `Opal" and did not differ much between trees on the various rootstocks.