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The proportion of Norwegian wheat used for food has varied significantly during the recent decade, mainly because of the instability of factors that are essential to baking quality (i.e. protein content and gluten functionality). During the same period, serious contamination of Fusarium spp. and mycotoxins was observed in some grain lots [1, 2]. A project was established to generate greater knowledge of the interface between gluten functionality and effects of Fusarium species and other microorganisms on Norwegian wheat quality. Instances of severe degradation of gluten proteins that resulted in an almost complete loss of gluten functionality were observed in some lots of Norwegian wheat. The degradation of the gluten appeared to be caused by exogenous proteases. Metabarcoding of fungi and bacteria in these grain lots identified fungi within the Fusarium Head Blight complex, as well as one bacterial species, as candidate species for influencing gluten functionality. Some of these candidates were inoculated on wheat during flowering [3]. Analysis of baking quality of the flour from this experiment revealed a reduced proportion of un-extractable polymeric proteins (%UPP) and severe reductions in the gluten’s resistance to stretching (RMAX) in wheat flour from plants inoculated with Fusarium graminearum. Flour from wheat inoculated with Fusarium avenaceum was generally less infested, and showed minimal or no reduction in gluten functionality and %UPP compared to flour from the F. graminearum infested samples. Flour from wheat inoculated with Michrodochium majus is yet to be analysed. References 1. Koga, S., et al., Investigating environmental factors that cause extreme gluten quality deficiency in winter wheat (Triticum aestivum L.). Acta Agriculturae Scandinavica, Section B—Soil & Plant Science, 2016. 66(3): p. 237-246. 2. Hofgaard, I., et al., Associations between Fusarium species and mycotoxins in oats and spring wheat from farmers’ fields in Norway over a six-year period. World Mycotoxin Journal, 2016. 9(3): p. 365-378. 3. Nielsen, K.A.G., Effect of microorganisms on gluten quality in wheat., in Faculty of Biosciences. 2017, Norwegian University of Life Sciences: Ås.

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High concentrations of the mycotoxins HT-2 and T-2 (HT2 + T2), primarily produced by Fusarium langsethiae, have occasionally been detected in Norwegian oat grains. In this study, we identified weather variables influencing accumulation of HT2 + T2 in Norwegian oat grains. Oat grain samples from farmers’ fields were collected together with weather data (2004–2013). Spearman rank correlation coefficients were calculated between the HT2 + T2 contamination in oats at harvest and a range of weather summarisations within estimated phenological windows of growth stages in oats (tillering, flowering etc.). Furthermore, we developed a mathematical model to predict the risk of HT2 + T2 in oat grains. Our data show that adequate predictions of the risk of HT2 + T2 in oat grains at harvest can be achieved, based upon weather data observed during the growing season. Humid and cool conditions, in addition to moderate temperatures during booting, were associated with increased HT2 + T2 accumulation in harvested oat grains, whereas warm and humid weather during stem elongation and inflorescence emergence, or cool weather and absence of rain during booting reduced the risk of HT2 + T2 accumulation. Warm and humid weather immediately after flowering increased the risk, while moderate to warm temperatures and absence of rain during dough development, reduced the risk of HT2 + T2 accumulation in oat grains. Our data indicated that HT2 + T2 contamination in oats is influenced by weather conditions both pre- and post-flowering. These findings are in contrast with a previous study examining the risk of deoxynivalenol contamination in oat reporting that toxin accumulation was mostly influenced by weather conditions from flowering onwards.

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Fusarium head blight and seedling blight, both caused by Fusarium spp. and Microdochium spp., and glume blotch caused by Parastagonospora nodorum, are important diseases in wheat. In Norway, wheat seed lots are routinely analysed for infestation by these pathogens using traditional methods (plating grain on PDA, recording presence or absence of fungal colonies). This method is time consuming, require knowledge within fungal morphology, and do not facilitate identification to species in all cases. Molecular methods such as quantitative PCR (qPCR) could allow detection and quantification of fungal DNA at the species level in a relatively time effective way, particularly since the method allows for automation in different steps such as DNA extraction and pipetting. Whether the latter method is suitable within seed health evaluations will depend on the relationship between the amount of DNA of the different fungal species and field performance, and the purpose of the test (evaluation of planting value, need for seed treatment, survey of fungal species, quality of grain for consumption etc). To compare the two different methods, about 150 spring wheat seed lots from the years 2016-2017 (including two cultivars) were selected for the analysis of different fungi using species-specific qPCR and compared with the results from routine testing on PDA. In the 2016 material (81 samples), a mean seed infestation rate of 26% was observed for Microdochium spp. in the PDA test. The level of Fusarium was lower (mean infestation rate of 5%). A strong relationship was observed between the percentage of seeds infested by Microdochium and the level of Microdochium DNA (sum of DNA from Microdochium majus and Microdochium nivale) quantified by qPCR (R2 of 0.76, p<0.01). The relationship between Fusarium infested seeds and the level of Fusarium DNA (sum of DNA from three species) was moderate (R2 of 0.33, p<0.01). The samples were also analysed for the presence of P. nodorum. Compared to Fusarium and Microdochium, P. nodorum was present at an intermediate level (mean infestation rate of 12%). The relationship between the two different methods was weaker for this fungus (R2 of 0.21, p<0.01) than for Fusarium and Microdochium. The relationship between germination capacity and rating of the three groups of fungi by either method was studied. Preliminary results suggest that of the three fungi, Microdochium was associated with germination capacity in the 2016 material, and that the Microdochium infestation rate on PDA was slightly better correlated to germination capacity than the level of Microdochium DNA. Further results will be presented at the conference, including the association between the relative DNA content of the different Microdochium and Fusarium species and seed germination.

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Different seed lots of Pinus spp. cultivated within South Africa were screened for the presence or absence of seed-borne fungi according to modified ISTA (International Seed Testing Association) prescribed protocols. Numerous (454 isolates) fungi were successfully isolated, purified and stored using agar slants and cryopreservation. Sydowia polyspora was isolated from six different seed lots from three Pinus species (P. greggii (South), P. elliottii and P. taeda) and was morphologically and molecularly identified. Koch’s postulates was fulfilled by inoculating one year old seedlings (wounded and unwounded) with a spore suspension (107 ml-1) obtained from 30 day old pure cultures grown on PDA. Inoculated and uninoculated control seedlings were incubated in a greenhouse at 220C until symptom development. Sydowia polyspora was re-isolated from symptomatic needles with both wounded and unwounded needles showing characteristic symptoms. No symptoms were apparent on the control seedlings. To the best of our knowledge, this is the first report of the fungus being isolated and recorded within the country. Further investigations will look at the prevalence, pathogenicity and characterization of the fungus within South Africa.

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Sclerotinia stem rot (SSR) is the most important disease of oilseed Brassica crops in Norway. Fungicide applications should be aligned with the actual need for control, but the SSR prediction models used lack accuracy. We have studied the importance of precipitation, and the role of petal and leaf infection for SSR incidence by using data from Norwegian field and trap plant trials over several years. In the trials, SSR incidence ranged from 0 to 65%. Given an infection threshold of 25% SSR, regression and Receiver Operating Characteristics (ROC) analysis were used to evaluate different precipitation thresholds. The sum of precipitation two weeks before and during flowering appeared to be a poor predictor for SSR infection in our field and trap plant trials (P = 0.24, P = 0.11, respectively). Leaves from three levels (leaf one, three, five), and petals were collected at three to four different times during flowering from nine field sites over two years and tested for SSR infection with real-time PCR. Percentage total leaf and petal infection explained 57 and 45% of variation in SSR incidence, respectively. Examining the different leaves and petals separately, infection of leaf three sampled at full flowering showed the highest explanation of variation in later SSR incidence (R2 = 65%, P < 0.001). ROC analysis showed that given an infection threshold of 45%, both petal and leaf infection recommended spraying when spraying was actually needed. Combining information on petal and leaf infection during flowering with relevant microclimate factors in the canopy, instead of the sum of precipitation might improve prediction accuracy for SSR.

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The Svalbard Global Seed Vault was opened in 2008. The aim was to secure genetic diversity of crop plants important to future food production. The Seed Vault has the capacity to store 4.5 million seed samples, each containing on average 500 seeds sealed in airtight aluminum bags. By the end of 2016, the Vault had approximately 880,000 accessions representing more than 5000 plant species. The samples, originating from 71 gene banks and research institutes from all across the world, include major food crops such as wheat, rice, barley, sorghum, maize, legumes and forage crops, and vegetables. The seed samples are duplicates (backups) of seed stored in national, regional and international gene banks. Deposits can only be made by following a depositor agreement and the seed samples in the Vault remain the property of the depositing gene bank. The Vault is situated in permafrost at -3 to -4°C, but artificial cooling maintains a temperature of -18°C inside the Vault. Management of the Vault is secured through an agreement between the Norwegian Ministry of Agriculture and Food, the Crop Trust and the Nordic Genetic Resource Centre (NordGen). Secure storage of gene bank seeds in Svalbard was initiated during the 1980s, when the Nordic Gene Bank placed a collection of seed duplicates in an abandoned coal mine outside Longyearbyen in Svalbard. In addition to the secure storage of the base collection, a study of the longevity (germination and seed health) in long-term storage (100 years) in permafrost was started in 1986. A total of 42 seed samples of 16 common agricultural and horticultural Nordic species were included in the study. A set of sub-samples has been taken out for analyses every two and a half years during the first 20 years, and are taken out every five years for the next 80 years.

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The estimated potential yield losses caused by plant pathogens is up to 16% globally (Oerke 2006) and most research in plant pathology aims to reduce yield loss in our crops directly or indirectly. Yield losses caused by a certain disease depend not only on disease severity, but also on the weather factors, the pathogen’s aggressiveness, and the ability of the crop to compensate for reduced photosynthetic area. The yield loss-disease relationship in a certain host-pathogen system might therefore change from year to year, making predictions for yield loss very difficult at the regional or even at the farmer’s level. However, estimating yield losses is essential to determine disease management thresholds at which acute control measures such as fungicide applications, or strategic measures such as crop rotation or use of resistant cultivars are economically and environmentally sensible. Legislation in many countries enforces implementation of integrated pest management (IPM), based on economic thresholds at which the costs due to a disease justify the costs for its management. Without a better understanding of the relationship between disease epidemiology and yield loss, we remain insufficiently equipped to design adequate IPM strategies that will be widely adapted in agriculture. Crop loss studies are resource demanding and difficult to interpret for one particular disease, as crops are usually not invaded by only one pest or pathogen at a time. Combining our knowledge on disease epidemiology, crop physiology, yield development, damage mechanisms involved, and the effect of management practices can help us to increase our understanding of the disease-crop loss relationship. The main aim of this paper is to review and analyze the literature on a representative host-pathogen relationship in an important staple food crop to identify knowledge gaps and research areas to better assess yield loss and design management strategies based on economic thresholds. Wheat is one of the most important staple foods worldwide and is susceptible to several important plant diseases. In our article, we focus on Septoria nodorum blotch (SNB) or Glume blotch of wheat as an example for a stubble-borne, seed-transmitted disease with a worldwide distribution causing considerable and regular yield losses. In their review on yield losses due to wheat pathogens in Australia, Murray and Brennan (2009) estimated the current annual economic loss due to SNB as high as $108 × 106, with potential costs as high as $230 × 106. The causal fungus, Parastagonospora nodorum, is currently serving as a model organism for molecular studies of the intimate relationship between necrotic effector-producing fungal strains and their corresponding susceptibility genes present in wheat cultivars (Oliver et al. 2012). In this paper, we analyze the literature on the biology of this common wheat pathogen, the yield loss it reportedly has caused, and the effect of control strategies to reduce this loss. Based on this analysis, we will evaluate the use of common management practices to reduce disease-related yield loss and identify related research needs.

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Deoxynivalenol (DON) is the most common mycotoxin in Norwegian cereals, and DON is detected in most samples of crude cereal grain and cereal food commodities such as flour, bran, and oat flakes. The Norwegian Scientific Committee for Food Safety assessed the risk for adverse effects of deoxynivalenol (DON) in different age groups of the domestic population. This review presents the main results from the risk assessment, supplemented with some recently published data. Impairment of the immune system together with reduced feed intake and weight gain are the critical effects of DON in experimental animals on which the current tolerable daily intake was established. Based on food consumption and occurrence data, the mean exposure to DON in years with low and high levels of DON in the flour, respectively, were in the range of or up to two times the Tolerable Daily Intake (TDI) in 1-year-old infants and 2-year-old children. In years with high mean DON concentration, the high (95th-percentile) exposure exceeded the TDI by up to 3.5 times in 1-, 2- , 4-, and 9-year-old children. The assessment concluded that exceeding the TDI in infants and children is of concern. The estimated dietary DON intakes in adolescent and adult populations are in the range of the TDI or below, and are not a health concern. Acute human exposure to DON is not of concern in any age group.

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During August 2013, white-grayish lesions, typical of Sclerotinia stem rot, had developed around leaf axils on the stems of turnip rape ‘Pepita’ in a field at the NIBIO research station Apelsvoll in Oppland County, Norway. Sclerotia were collected from inside infected turnip rape stubble and from harvested seeds, surface sterilized, bisected, and placed onto potato dextrose agar (PDA). Following 1 to 2 days incubation at 20°C, fast-growing white mycelium characteristic of Sclerotinia was observed, and within 5 to 7 days, new sclerotia had started to develop. Sclerotia size and growing pattern although variable was characteristic of S. sclerotiorum. DNA extraction, PCR amplification, and sequencing of the ITS regions of the rDNA was then carried out for 20 isolates. BLASTn analysis of 475 bp amplicons showed that 15 isolates were S. sclerotiorum, while five were identified as S. subarctica (previously called Sclerotinia sp 1; Holst-Jensen et al. 1998; Winton et al. 2006, 2007), with 100% identity to a U.K. S. subarctica isolate (Clarkson et al. 2010). A representative ITS region sequence was deposited in GenBank (accession no. KX929095). The identity of the S. subarctica isolates was further confirmed by the lack of a 304-bp intron in the LSU rDNA compared with S. sclerotiorum (Holst-Jensen et al. 1998), which was visualized by PCR amplification and gel electrophoresis. Sclerotia of two S. subarctica isolates were placed on PDA and incubated for 7 days. Agar plugs of actively growing mycelium were used for the pathogenicity testing of spring oilseed rape plants (‘Mosaik’) in the greenhouse. Plants were inoculated at growth stage BBCH 57/59 (preflowering) and BBCH 64 (40% of flowers open) by attaching two PDA plugs of actively growing mycelium per main stems with small needles, using four plants per treatment. Noninoculated PDA agar plugs were attached to the control plants. The experiment was repeated three times. Symptoms typical of stem rot appeared after 1 to 2 weeks of incubation at 16 to 20°C, 100% relative humidity. Stems started to develop white lesions with fluffy mycelium around the inoculation sites. Control plants did not show the characteristic symptoms for Sclerotinia infection. After senescence of the plants, sclerotia were collected from inside the stems and cultured on PDA. White mycelium started to grow after 1 to 2 days and new sclerotia were formed within 7 days, similar to the ones used for producing the initial isolate. Brassica oil seed crops are cultivated as important break crops in the cereal-based production system in Norway and can be severely affected by Sclerotinia stem rot. The disease is observed in all regions where Brassica oil seed crops are grown, and in severe cases, a reduction in oilseed yield of 25% has been recorded in untreated control treatments of fungicide trials. Although S. subarctica has been previously reported on wild hosts (Holst-Jensen et al. 1998), this is the first report of the pathogen on a crop plant in Norway. In the United Kingdom, Clarkson et al. (2010) demonstrated pathogenicity of S. subarctica isolated from Ranunculus acris on oilseed rape. As symptoms for S. subarctica and S. sclerotiorum are indistinguishable, S. subarctica might be present undetected in many farmer fields.

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Fleire soppar kan angripa kongler av gran (Picea spp.) og føra til dårleg spiring av frø. Frøsmitte kan også overførast til planter og gjera skade seinare i omløpet, både i planteskular og i produksjonsfelt til skog og juletre.

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Sclerotinia species are important fungal pathogens of a wide range of crops and wild host plants. While the biology and population structure of Sclerotinia sclerotiorum has been well-studied, little information is available for the related species S. subarctica. In this study, Sclerotinia isolates were collected from different crop plants and the wild host Ranuculus ficaria (meadow buttercup) in England, Scotland, and Norway to determine the incidence of Sclerotinia subarctica and examine the population structure of this pathogen for the first time. Incidence was very low in England, comprising only 4.3% of isolates while moderate and high incidence of S. subarctica was identified in Scotland and Norway, comprising 18.3 and 48.0% of isolates respectively. Characterization with eight microsatellite markers identified 75 haplotypes within a total of 157 isolates over the three countries with a few haplotypes in Scotland and Norway sampled at a higher frequency than the rest across multiple locations and host plants. In total, eight microsatellite haplotypes were shared between Scotland and Norway while none were shared with England. Bayesian and principal component analyses revealed common ancestry and clustering of Scottish and Norwegian S. subarctica isolates while English isolates were assigned to a separate population cluster and exhibited low diversity indicative of isolation. Population structure was also examined for S. sclerotiorum isolates from England, Scotland, Norway, and Australia using microsatellite data, including some from a previous study in England. In total, 484 haplotypes were identified within 800 S. sclerotiorum isolates with just 15 shared between England and Scotland and none shared between any other countries. Bayesian and principal component analyses revealed a common ancestry and clustering of the English and Scottish isolates while Norwegian and Australian isolates were assigned to separate clusters. Furthermore, sequencing part of the intergenic spacer (IGS) region of the rRNA gene resulted in 26 IGS haplotypes within 870 S. sclerotiorum isolates, nine of which had not been previously identified and two of which were also widely distributed across different countries. S. subarctica therefore has a multiclonal population structure similar to S. sclerotiorum, but has a different ancestry and distribution across England, Scotland, and Norway.

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Over the recent decades, the Norwegian cereal industry has had major practical and financial challenges associated with the occurrence of Fusarium and mycotoxins in cereal grains. From 2011, payment reductions to farmers were implemented for oat grain lots with high levels of deoxynivalenol (DON). However, according to preliminary results by NIBIO, NMBU and Graminor, certain oat varieties with generally medium or low DON contamination, may contain high levels of HT-2 and T-2-toxins (HT2+T2). These mycotoxins, formed by Fusarium langsethiae, are considerably more toxic than DON. Resistance to F. langsethiae is not included in the variety screening in Norway. In 2016 a new project, SafeOats, was initiated. This project is led by NIBIO and is a collaboration between NIBIO, NMBU, Kimen, and the main Norwegian and Swedish breeding companies, Graminor and Lantmännen. Harper Adam University (UK) and Julius Kühn-Institut (Germany) are international collaborators. SafeOats will develop resistance screening methods in order to facilitate the phase-out of susceptible oat germplasm. Furthermore, SafeOats will give new insight into the biology of F. langsethiae and HT2+T2 accumulation in oats, and thus facilitate the choice of relevant control measures. The results from SafeOats will benefit consumers nationally and internationally by providing tools to increase the share of high quality grain into the food and feed industry. SafeOats is financed by The Foundation for Research Levy on Agricultural Products/Agricultural Agreement Research Fund/Research Council of Norway with support from the industry partners Graminor, Lantmännen, Kimen, Felleskjøpet Agri, Felleskjøpet Rogaland Agder, Fiskå Mølle Moss, Norgesmøllene and Strand Unikorn/Norgesfor.

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During the last ten years, Norwegian cereal grain industry has experienced large challenges due to Fusarium spp. and Fusarium mycotoxin contamination of small-grained cereals. To prevent severely contaminated grain lots from entering the grain supply chain, it is important to establish surveys for the most prevalent Fusarium spp. and mycotoxins. The objective of our study was to quantify and calculate the associations between Fusarium spp. and mycotoxins prevalent in oats and spring wheat. In a 6-year period from 2004-2009, 178 grain samples of spring wheat and 289 samples of oats were collected from farmers’ fields in South East Norway. The grains were analysed for 18 different Fusarium-mycotoxins by liquid chromatography – mass spectrometry. Generally, the median mycotoxin levels were higher than reported in Norwegian studies covering previous years. The DNA content of Fusarium graminearum, Fusarium culmorum, Fusarium langsethiae, Fusarium poae and Fusarium avenaceum were determined by quantitative PCR. We identified F. graminearum as the main deoxynivalenol (DON) producer in oats and spring wheat, and F. langsethiae as the main HT-2 and T-2-toxins producer in oats. No association was observed between quantity of F. graminearum DNA and quantity of F. langsethiae DNA nor for their respective mycotoxins, in oats. F. avenaceum was one of the most prevalent Fusarium species in both oats and spring wheat. The following ranking of Fusarium species was made based on the DNA concentrations of the Fusarium spp. analysed in this survey (from high to low): F. graminearum = F. langsethiae = F. avenaceum > F. poae > F. culmorum (oats); F. graminearum = F. avenaceum > F. culmorum > F. poae = F. langsethiae (spring wheat). Our results are in agreement with recently published data indicating a shift in the relative prevalence of Fusarium species towards more F. graminearum versus F. culmorum in Norwegian oats and spring wheat.

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High concentrations of the mycotoxin deoxynivalenol (DON), produced by Fusarium graminearum have occurred frequently in Norwegian oats recently. Early prediction of DON levels is important for farmers, authorities and the Cereal Industry. In this study, the main weather factors influencing mycotoxin accumulation were identified and two models to predict the risk of DON in oat grains in Norway were developed: (1) as a warning system for farmers to decide if and when to treat with fungicide, and (2) for authorities and industry to use at harvest to identify potential food safety problems. Oat grain samples from farmers’ fields were collected together with weather data (2004–2013). A mathematical model was developed and used to estimate phenology windows of growth stages in oats (tillering, flowering etc.). Weather summarisations were then calculated within these windows, and the Spearman rank correlation factor calculated between DON-contamination in oats at harvest and the weather summarisations for each phenological window. DON contamination was most clearly associated with the weather conditions around flowering and close to harvest. Warm, rainy and humid weather during and around flowering increased the risk of DON accumulation in oats, as did dry periods during germination/seedling growth and tillering. Prior to harvest, warm and humid weather conditions followed by cool and dry conditions were associated with a decreased risk of DON accumulation. A prediction model, including only pre-flowering weather conditions, adequately forecasted risk of DON contamination in oat, and can aid in decisions about fungicide treatments.

Sammendrag

The proportion of Norwegian wheat used for food has recently been dramatically lower due to both reduced production and poor quality. Furthermore, the Norwegian milling and baking industries have experienced major challenges in utilizing Norwegian wheat due to the instability of factors, such as protein content and gluten functionality, that are of major importance for baking quality. The variation in the wheat quality can itself cause economic losses for the milling and baking industry due to uncertainty in the marketplace. In the same period as a large variation in baking quality was reported in Norwegian wheat, serious contamination of Fusarium spp. and mycotoxins were observed in some grain lots. We have revealed the severe degradation of gluten proteins in some Norwegian wheat samples leading to an almost complete loss in the gluten functionality. The degradation of the gluten appears to be caused by exogenous proteases, and was associated with the presence of Fusarium spp., and their metabolites, and other microorganisms in the wheat. Increased knowledge is needed to establish the cause of the poor gluten functionality and to develop control measures to reduce the amount of poor quality wheat entering the food value chain. In 2014, a new project was established to generate deeper knowledge in the interface between gluten functionality and effects of Fusarium spp. and other microorganism on wheat quality, and to better utilize Norwegian wheat grown in this challenging environment. A metagenomic analysis, designed to identify microorganisms associated with reduced baking quality, has been undertaken. To study the influence of the identified microorganisms and their metabolites on gluten functionality, wheat plants were inoculated with microorganisms, selected based upon the results of the metagenomics study. Fusarium species are among those microorganisms being tested.

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This paper presents peer-reviewed studies comparing the content of deoxynivalenol (DON), HT-2+T-2 toxins, zearalenone (ZEA), nivalenol (NIV), ochratoxin A (OTA) and fumonisins in cereal grains, and patulin (PAT) in apple and apple-based products, produced in organically and conventionally grown crops in temperate regions. Some of the studies are based on data from controlled field trials, however, most are farm surveys and some are food basket surveys. Almost half of the studies focused on DON in cereals. The majority of these studies found no significant difference in DON content in grain from the two farming systems, but several studies showed lower DON content in organically than in conventionally produced cereals. A number of the investigations reported low DON levels in grain, far below the EU limits for food. Many authors suggested that weather conditions, years, locations, tillage practice and crop rotation are more important for the development of DON than the type of farming. Organically produced oats contained mainly lower levels of HT-2+T-2 toxins than conventionally produced oats. Most studies on ZEA reported no differences between farming systems, or lower concentrations in organically produced grain. For the other mycotoxins in cereals, mainly low levels and no differences between the two farming systems were reported. Some studies showed higher PAT contamination in organically than in conventionally produced apple and apple products. The difference may be due to more efficient disease control in conventional orchards. It cannot be concluded that any of the two farming systems increases the risk of mycotoxin contamination. Despite no use of fungicides, an organic system appears generally able to maintain mycotoxin contamination at low levels. More systematic comparisons from scientifically controlled field trials and surveys are needed to clarify if there are differences in the risk of mycotoxin contamination between organically and conventionally produced crops.

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Fusarium and Microdochium may cause seedling blight and poor germination of cereal seeds. However, indications of poor survival of Fusarium in seed and improved germination after some months of storage have been observed. A study was carried out to investigate if seed storage can contribute to improved seed quality. Samples from seed lots of barley, oats and spring wheat were tested for germination capacity and Fusarium /Microdochium infection frequencies a few days after harvest, and after 5, 12 and 15 months of storage. In barley, the average germination percentage increased slightly, from 92% at harvest to 95% after five months of storage. In oats, the average germination percentage increased from 82% to 85% during the first five months. In spring wheat, the average germination percentage was reduced from 81% at harvest to 67% after five months. In barley and oats, average Fusarium /Microdochium frequencies were reduced during storage, with the highest reduction observed during the first five months (from 50% to 37%, and from 60% to 46%, barley and oats respectively). In spring wheat, no significant reduction in average infection level was recorded (58% at harvest, 50% after 15 months of storage). There was however, variation between seed lots in all three cereal species in both germination percentage and Fusarium /Microdochium frequencies during the storage period. It is concluded that storage of barley and oats seeds for 5 months after harvest may in some cases increase the seed quality and thereby meet the certification requirements of minimum 85% germination.

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The plant pathogenic fungus Fusarium langsethiae produces the highly potent mycotoxins HT-2 and T-2. Since these toxins are frequently detected at high levels in oat grain lots, they pose a considerable risk for food and feed safety in Norway, as well as in other north European countries. To reduce the risk of HT-2/T- 2-contaminated grain lots to enter the food and feed chain, it is important to identify factors that influence F. langsethiae infection and mycotoxin development in oats. However, the epidemiology of F. langsethiae is unclear. A three-year survey was performed to reveal more of the life cycle of F. langsethiae and its interactions with oats, other Fusarium species, as well as insects, mites and weeds. We searched for inoculum sources by quantifying the amount of F. langsethiae DNA in weeds, crop residues, and soil, sampled from a predetermined selection of oat-fields. To be able to define the onset of infection, we analysed the amount of F. langsethiae DNA in oat plant material sampled at selected growth stages (between booting and maturation), as well as the amount of F. langsethiae DNA and HT-2 and T-2 toxins in the mature grain. We also studied the presence of possible insect- and mite vectors sampled at the selected growth stages using Berlese funnel traps. All the different types of materials were also analysed for the presence F. graminearum DNA, the most important deoxynivalenol producer observed in Norwegian cereals, and which presence has shown a striking lack of correlation with the presence F. langsethiae in oat. Preliminary results show that F. langsethiae DNA may occur in the oat plant before heading and flowering. Some F. langsethiae DNA was observed in crop residues and weeds, though at relatively low levels. More results from this work will be presented at the meeting.

Sammendrag

The plant pathogenic fungus Fusarium langsethiae produces the highly potent mycotoxins HT-2 and T-2. Since these toxins are frequently detected at high levels in oat grain lots, they pose a considerable risk for food and feed safety in Norway, as well as in other north European countries. To reduce the risk of HT-2/T- 2-contaminated grain lots to enter the food and feed chain, it is important to identify factors that influence F. langsethiae infection and mycotoxin development in oats. However, the epidemiology of F. langsethiae is unclear. A three-year survey was performed to reveal more of the life cycle of F. langsethiae and its interactions with oats, other Fusarium species, as well as insects, mites and weeds. We searched for inoculum sources by quantifying the amount of F. langsethiae DNA in weeds, crop residues, and soil, sampled from a predetermined selection of oat-fields. To be able to define the onset of infection, we analysed the amount of F. langsethiae DNA in oat plant material sampled at selected growth stages (between booting and maturation), as well as the amount of F. langsethiae DNA and HT-2 and T-2 toxins in the mature grain. We also studied the presence of possible insect- and mite vectors sampled at the selected growth stages using Berlese funnel traps. All the different types of materials were also analysed for the presence F. graminearum DNA, the most important deoxynivalenol producer observed in Norwegian cereals, and which presence has shown a striking lack of correlation with the presence F. langsethiae in oat. Preliminary results show that F. langsethiae DNA may occur in the oat plant before heading and flowering. Some F. langsethiae DNA was observed in crop residues and weeds, though at relatively low levels. More results from this work will be presented at the meeting.

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Hvilken jordarbeiding som benyttes i den enkelte kornåker påvirker blant annet avlingsmengde, kvaliteten på kornet og miljøet. I denne publikasjonen er det samlet informasjon om effekter av ulik jordarbeiding, som hjelp til korndyrkere ved vurdering av jordarbeidingsmetoder, og for myndigheter ved beslutninger om jordarbeiding i regionale miljøprogram (RMP).

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Forsøksresultatene som presenteres i denne rapporten er biologisk godkjenningsprøving av soppmidler utført på oppdrag fra Mattilsynet i 2014. Inkludert i rapporten er også forsøk eller egne forsøksledd som grupperes som biologisk utviklingsprøving. Forsøkene er utført etter GEP-kvalitet1 hvis ikke annet er nevnt. Dette innebærer at det er utarbeidet skriftlige prosedyrer for nesten alle arbeidsprosesser. Disse prosedyrene, kalt standardforskrifter (SF’er), er samlet i en kvalitetshåndbok. Denne er delt ut til alle personer som arbeider med utprøving av plantevernmidler. De samme personene har også vært med på et endagskurs i GEP-arbeid.

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In 2008, an epidemic caused by a new Neonectria sp. was discovered on white fir (Abies concolor) in several counties in southern Norway [1]. Later the pathogen was also found on other fir species in Norway and Denmark [2]. Typical symptoms and signs were dead shoots, flagging (dead branches), canker wounds, heavy resin flow, and occasionally red fruiting bodies (perithecia). Pathogenicity tests on several Abies spp. proved the fungus to be very aggressive, which corresponds well with observations of mortality of white fir and subalpine fir (A. lasiocarpa) from different age classes under field conditions. Sequencing of the internal transcribed regions (ITS) of the ribosomal DNA showed that this Neonectria sp. was most similar to N. ditissima (only 5 bp different from isolates in the GenBank), a common pathogen worldwide on broad leaf trees. The ITS sequences were very different (> 20 bp) from N. fuckeliana, a well-known fungus on Norway spruce in Scandinavia and other parts of the world, especially in the northern hemisphere. In 2011, the new Neonectria species was found on diseased trees in a Danish nordmann fir (Abies nordmanniana) seed orchard. Resin flow was seen from mature cones, and tests revealed that the seeds were infected by the Neonectria sp.

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Norsk juletreproduksjon har de siste årene hatt stor vekst, og det har spesielt blitt satset på edelgran (Abies spp.). Dette har ført til uforutsette sykdomsproblemer. Blant annet gjør soppen Sydowia polyspora, som også har vist seg å være frøoverført, stor skade. Vi har i den forbindelse forsøkt å finne effektive metoder for å eliminere frøsmitten samtidig som spireevnen opprettholdes.

Sammendrag

Forsøksresultatene som presenteres i denne rapporten er biologisk godkjenningsprøving av soppmidler utført på oppdrag fra Mattilsynet i 2012. Inkludert i rapporten er også forsøk eller egne forsøksledd som grupperes som biologisk utviklingsprøving. Forsøkene er utført etter GEP-kvalitet1 hvis ikke annet er nevnt. Dette innebærer at det er utarbeidet skriftlige prosedyrer for nesten alle arbeidsprosesser. Disse prosedyrene, kalt standardforskrifter (SF’er), er samlet i en kvalitetshåndbok. Denne er delt ut til alle personer som arbeider med utprøving av plantevernmidler. De samme personene har også vært med på et endagskurs i GEP-arbeid.

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Aksfusariose er en utbredt og destruktiv sjukdom i korn som kan forårsakes av en rekke ulike sopparter innen slekta Fusarium. I tillegg til å redusere avlingsmengde, kvalitet og frøspiring, kan ulike Fusarium-arter produsere en rekke ulike soppgifter (mykotoksiner) som kan være giftige for mennesker og dyr. Fuktige værforhold i perioden rundt blomstring av kornet ser ut til å øke risikoen for angrep av Fusarium. I tillegg kan dyrkningspraksis påvirke forekomsten av aksfusariose og utvikling av mykotoksiner i kornet.

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Plogen har tradisjonelt vært viktig for å få et godt såbed, for innblanding av halmrester og gjødsel i jorda, og for god bekjemping av ugras og sjukdommer. Redusert jordarbeiding uten bruk av plogen, gir imidlertid store miljøfordeler i form av mindre erosjon og utvasking av næringsstoffer. Denne rapporten fokuserer på konsekvenser av ulik jordarbeiding på plantevernsituasjonen i korn. Basert på dagens kunnskap fra norske og internasjonale studier konkluderes det med at redusert jordarbeiding gir økt risiko for utvikling av ugras og plantesjukdommer, samt mykotoksiner. I tillegg kan redusert jordarbeiding føre til økt bruk av kjemiske plantevernmidler som glyfosat, fenoksysyrer og soppmidler. Ugraset og de fleste plantesjukdommer kan som regel bekjempes med plantevernmidler, mens Fusarium spp. og mykotoksiner bare delvis kan bekjempes av kjemiske midler. Miljørisikoen av kjemiske plantevernmidler påvirkes av egenskaper til plantevernmidlene. Redusert jordarbeiding fører til økt risiko for transport til grunnvann av fenoksysyrer og lavdosemidler (sulfonylurea-preparater). Risiko for transport til overflatevann av ugrasmidler og soppmidler er minst når åkeren ligger i stubb. Været og klimaet har stor betydning for utvikling av skadegjørerne, risiko for utvikling av mykotoksiner og utvasking av plantevernmidler. Vårpløying kan være gunstig miljømessig sett fordi det kan redusere erosjon og næringsstofftap. Samtidig gir det mindre behov for, og derfor redusert miljørisiko av, plantevernmidler enn andre typer jordarbeiding. Vårpløying egner seg derimot dårlig på stiv leirjord, det fører til større tidspress på våren og risiko for forsinka våronn og derved lavere avling.

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Sydowia polyspora was found to be seed borne on true fir (Abies spp.) where it is associated with two serious diseases; current season needle necrosis (CSNN) and Sclerophoma shoot dieback [1]. To our knowledge, S. polyspora was previously only reported to be seed borne on Scots pine (Pinus sylvestris) [3]. In 2009, we discovered S. polyspora on Norway spruce (Picea abies) seedlings from germination tests at the Norwegian Forest Seed Center. This indicated that S. polyspora also was seed borne on spruce. Based on this, we wanted to investigate how widespread S. polyspora was on conifer seeds. In 2010, we tested 44 seed lots from 8 genera. S. polyspora was isolates from seeds from the following genera; Abies, Larix, Picea, Pinus, Pseudotsuga, Thuja, and Tsuga. Interestingly, they are the exact same genera that Funk [2] reported S. polyspora from on diseased foliage and shoots. We found S. polyspora on Norway spruce harvested in 1970, thus, the fungus may survive for decades in seed lots. In Norway, Sclerophoma shoot dieback has been found on Norway spruce in Christmas tree fields. Fungal species from a number of other genera were also detected in the seed test, but here we only report S. polyspora.

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Sydowia polyspora is a pathogenic, seed borne fungus on conifers [1]. It is especially troublesome in the Christmas tree industry, where it causes current season needle necrosis (CSNN) on fir (Abies spp.). Needles get chlorotic spots or bands and in severe cases the entire needles turn necrotic and shed. The fungus also commonly kills current year shoots (Sclerophoma shoot dieback) on both fir and spruce (Picea spp.). The latter we proved on subalpine fir (A. lasiocarpa) inoculated by S. polyspora from noble fir (Abies procera) seeds. Two conifer seed lots known from previous tests to contain a high percentage of S. polyspora were selected for a treatment experiment; alpine pine (Pinus mugo var. rotundata) and Noble fir. Both seed lots received the following five treatments; surface sterilized (10 sec. in 70 % ethanol plus 90 sec. in 0,5 % NaOCl), dipped in 15 % acidic acid, mixed with 0,36 gram Signum (boskalid and pyraklostrobin) per 100 gram seeds, mixed with 0,8 gram Mycostop (Streptomyces griseovirides) per 100 gram seeds, dipped in different concentrations of thyme oil (extracted from Thymus vulgaris), and control (no treatment). Based on the results we recommend Signum for conifer seed treatment. This fungicide controlled S. polyspora well and did not influence on the germination ability. Agricultural

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Forecasting models for prediction of diseases and pests in crop plants are helpful tools in decision support systems for crop management.  Correct use of pesticides may result in optimal effect, increased yield and better quality of the crop, while minimizing the environmental strain and costs. In Norway, a range of decision support systems for diseases, pests and weeds are available through the internet service VIPS (www.vips-landbruk.no). The reliability of disease and pest forecasts depends on robust forecasting models and relevant weather data. Although weather data are collected from a network of 80 weather stations located in agricultural production areas in Norway, many farms are remotely located from a weather station. The accuracy of forecasts relies on distance and geographical variation from the farm site to the nearest weather station. Forecasts for pest or diseases can be tailored to fit the local conditions at a farm site by use of weather forecasts and radar measured rainfall. The use of this system will be of particular interest to farms located far from the nearest weather station. Also, locally adapted forecasts for pest or diseases promote a sense of ownership and personal interest in the forecasting systems provided. The Norwegian Meteorological Institute provide weather forecasts on a 4x4 km spatial resolution in rural areas on a 1 hour timescale, while radar measured rainfall has a 1x1 km spatial resolution on a 15 min time scale. These data are currently connected to the existing weather stations to predict warnings ahead of time. The new approach is to adapt these data to individual farm sites. Previous tests have shown that weather prognosis for rainfall is less accurate than weather prognosis for temperature, wind, air humidity and radiation. Estimated rainfall will therefore be based on radar measurements. As part of a pilot project, the use of farm scale forecasts to predict development of plant diseases were tested at 35 farms in the Solør-Odal district in Norway in 2010 and 2011. Preliminary results show that late-blight forecasts produced on a farm scale often differ from forecasts based on data from the nearest weather station, proving the significance of the local approach in farm scale forecasting. Predictions of DON (deoxynivalenol) concentration in oats at harvest based on farm scale weather data, compared to predictions based on weather data from the nearest weather station will also be studied. Future aspects will be to work towards an improved system where farmers throughout Norway can register their farm and automatically have access to a range of pest and disease forecasts based on site specific weather data.

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I 2005 undersøkte vi soppfloraen på frø av edelgran (Abies spp.). Mellom anna fann vi mykje Sydowia polyspora, soppen som fører til flekkar på årsnåler (CSNN /Current Season Needle Necrosis) og visne skot (Sclerophoma-skade). På bakgrunn av dette ville vi undersøkja om S. polyspora også kan førekoma på andre bartrefrø og inkluderte difor, i tillegg til edelgran, frøparti frå slektene Douglas (Pseudotsuga), furu (Pinus), gran (Picea), hemlokk (Tsuga), sypress (Chamaecyparis) og tuja (Thuja) i ein frøtest i 2010. S. polyspora vart funnen på frø i alle slektene. Her omtalar vi også andre soppfunn frå denne testen.  

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Gårdsvarsling gjør det mulig å beregne lokalt tilpassede plantevernvarsler ved bruk av værvarsel og radarmåling av nedbør. Vanligvis beregnes plantevernvarsler på grunnlag av data fra værstasjoner, men mange gårdsbruk ligger langt unna nærmeste målepunkt. For disse brukene vil varsler basert på værvarsler og radarmålt nedbør være et godt alternativ. Gårdsvarsler tilpasset det enkelte gårdsbruk vil derfor øke nytteverdien av varslingstjenesten innen planteskadegjørere (VIPS) for mange dyrkere.

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Aksfusariose er en kornsjukdom som kan angripe alle kornarter. Sjukdommen forårsakes av sopparter innen slekta Fusarium. Ulike Fusarium-arter kan produsere en rekke forskjellige mykotoksiner (soppgifter). Grenseverdier for innhold av enkelte mykotoksiner i korn og kornprodukter til mat og fôr er fastsatt av Mattilsynet (i henhold til EU’s regelverk). Denne dyrkningsveiledningen gir, på bakgrunn av dagens kunnskap, råd om hvordan en kan redusere risikoen for utvikling av mykotoksiner i korn.

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Varsling av angrep av potettørråte og aksfusariose mot enkeltgårdsbruk er prøvet ut for 35 gårdsbruk i Solø-Odal. Denne utprøvingen av gårdsvarsel er basert på fjernmåling av nedbør med radar og beregning av loakle værforhold basert på værvarslingsmodell. Foreløpige resultater fra evaluering av erfaringene fra 2010 er lovende. Samarbeidspartnere er Meteorologisk institutt, Solør-Odal Landbruksrådgivning og Bioforsk Plantehelse

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Current season needle necrosis (CSNN) has been a serious foliage disorder on noble fir (Abies procera), Normann fir (A. nordmanniana) and grand fir (A. grandis) in Europe and North America for more than 25 years. Approximately 2-4 weeks after bud break, needles develop chlorotic spots or bands that later turn necrotic. The symptoms were reported as a physiological disorder with unknown aetiology. In a recent study in Norway, Sydowia polyspora (anamorph: Hormonema dematioides) was found to cause CSNN. To determine if fungi found to cause diseases on fir (Abies spp.) might be seed borne, seed samples from Austria, Georgia, Russia, Canada and Norway were tested using agar plate methods. Some fungi were identified to species based on sequencing of ITS regions of rDNA. S polyspora was isolated from 10 of the 12 seed samples tested, representing all countries of the study. The fungus occurred in frequencies from 0.5 – 87%. Sirococcus conigenus, causing shoot blight of several conifer species, was found in a Norwegian A. procera seed lot (31% infected seeds), which to our knowledge is the first report of this pathogen on noble fir seed. Caloscypha fulgens, the seed or cold fungus, was recorded at low levels on subalpine fir from Canada. In addition the following fungus genera was recorded: Acremonium, Acremoniella, Alternaria, Aspergillus, Botrytis, Cephalosporium, Chaetomium, Cladosporium, Dictyopolyschema, Epicoccum, Fusarium, Genicularia, Mucor, Neonectria, Penicillium, Phoma, Rhizopus, Sordaria,  Trichoderma and Trichothecium, and an unidentified fungus. Species within some of these fungal genera are known pathogens in nurseries and production fields. In 2009, we discovered S. polyspora on samples of pine and spruce seedlings from germination tests at the Norwegian Forest Seed Center. Due to these latter findings, we tested 44 conifer seed lots for S. polyspora this year. The main results will be presented. There is reason to consider seeds infected with S. polyspora as an important source of inoculum for infection of young trees. To reduce the damages in production fields, and to limit the risk of long distance spread of important  seed borne diseases of conifers by international trade, seed health testing of fir seeds is recommended.

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The osmotic method has been used for many years in Norway and Sweden as a routine method for detection of Pyrenophora teres (anamorph Drechslera teres) and P. graminea (anamorph D. graminea) on barley. The method is based on the ability of Pyrenophora spp. to produce red pigments. However, it cannot distinguish between P. teres and P. graminea because they produce the same pigment. A validation study has been carried out with the aim to provide the necessary documentation for including the method in the International Rules for Seed Testing (ISTA Rules). Seven laboratories participated and each tested 3 x 300 seeds of three barley seed lots. Analyses of the results demonstrate that the method gives sufficient repeatability and there is no particular problem with this test at a laboratory level. Furthermore, in previous studies with the osmotic method organized by a Nordic working group, it has been shown that the osmotic method easily gives reproducible results for Pyrenophora teres/P. graminea in barley when used by experienced laboratories. Moreover, the osmotic method is well suited for routine analyses because it is quick and easy to carry out. The study showed, that if used correctly and with proper equipment the osmotic method for detection of Pyrenophora teres/P. graminea is easy to perform and it showed good conformity amongst laboratories.

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VIPS (Varsling Innen PlanteSkadegjørere) is a web-based forecasting and information service developed for integrated management of pests and diseases in cereals, vegetables and fruit crops. It also includes a decision support for management of weeds in cereals. VIPS was established in 2001 as a collaborative project between Bioforsk and Norwegian Agricultural Extension Service (NAES) under a government-funded action for reducing risk connected to the use of pesticides. The service is open and free of charge at www.vips-landbruk.no. Forecasting models that predict the likelihood of pest or disease outbreak can assist crop growers in determining when or if pesticides are needed. Reduced unneccesary fungicide applications will reduce the monetary and environmental costs asssociated with traditional spray programs. Inputs to the forecasting models in VIPS are weather data from the Bioforsk Agrometeorological Service consisting of a network of 80 automatic weather stations located across crop production areas, weather forecasts from the Norwegian Meteorological Institute and biological/field observations collected by NAES. A general interface is used for all models incorporated in the system, allowing new models to be implemented. Currently, VIPS includes forecasts and/or monitoring of leaf blotch diseases (Stagonospora nodorum Septoria tritici, Drechslera tritici-repentis) in wheat, net/spot blotch (Drechslera teres) and scald (Rhynchosporium secalis) in barley, Fusarium Head Blight (Fusarium spp)  in spring wheat and oats, stem rot (Sclerotinia sclerotiorum) in oil seed rape, potato late blight (Phytophthora infestans), cabbage moth (Mamestra brassicae), cabbage root fly (Delia radicum), turnip root fly (Delia floralis), carrot root fly (Psila rosae), the tarnished plant bug (Lygus rugulipennis) in vegetables, lettuce downy mildew (Bremia lactucae), celery late blight (Septoria apiicola), onion downy mildew (Peronospora destructor), apple scab (Venturia inequalis), codling moth (Cydia pomonella), apple fruit moth (Argyresthia conjugella) and grey mould (Botrytis cinerea) in strawberry. A preliminary model for calculation of the mycotoxin deoxynivalenol (DON) content in oats at harvest is also included. Models for additional pests/diseases are under development. During the growing season the monitoring of several pests and diseases are recorded through a message system in VIPS. Forecasts are also available as SMS messages. Current development aiming at transferring the service from weatherstation-based to farm-based forecasts is presented by Nordskog et al. at this seminar. The weed management component was developed in Denmark and has been adjusted to Norwegian conditions. It includes assessment of the need for control of weeds in cereal fields, eg choice of herbicide(s) and calculation of doses. Both experiments and practical large-scale testing of “VIPS weeds” have demonstrated the potential of a significant reduction in the use of herbicides in cereals.

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The increased occurrence of Fusarium toxins during recent years in Norwegian cereals, especially deoxynivalenol (DON) in spring wheat and DON and T-2/HT-2 toxins in oats (see abstract by Hofgaard et al), is a serious challenge for the cereal industry and farmers. Contamination levels above regulatory or advisory maximum limits have frequently been detected. In Norway, many farmers bring their grain directly to the buyer at harvest, and, in a time and cost perspective, it is not realistic to test all grain lots for mycotoxin content by chemical analysis. In order to reduce the risk of cereal grain lots with unacceptable Fusarium toxin content entering the feed and food chain, a three-step screening strategy has been developed in close cooperation with the cereal industry. 1 Toxin risk (DON, T-2/HT-2) in cereal fields will be predicted by models based on information on climatic conditions and agronomic/cultivation practice (see abstract by Elen et al). 2 Grain from "high-risk" fields will be analysed for mycotoxins by a rapid "on-site" test method (lateral flow tests) before the grain enters the silo/storage/mill. 3 Samples from lots with toxin levels close to the defined maximum limits (based on analyses in step 2) can be forwarded to chemical analyses for precise decision of the mycotoxin concentrations.

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I "Fusariumprosjektet" ved Bioforsk Plantehelse har vi i løpet av en 4 års periode (2006-2009) samlet inn kornprøver fra partier med norskprodusert havre og vårhvete med tilhørende opplysninger om klima og dyrkningsmessige forhold. Kornprøvene er videre analysert for innhold av 17 ulike mykotoksiner. Ved å sammenstille og analysere data og informasjon om de ulike kornprøvene, har vi kartlagt ulike faktorer som kan ha betydning for utvikling av mykotoksiner i kornet. Dataene er videre brukt for å utvikle varslingsmodeller for Fusarium-mykotoksiner i korn, og for utprøving av ulike hurtigmetoder som er utviklet for å måle innhold av mykotoksiner i korn.

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I "Fusariumprosjektet" ved Bioforsk Plantehelse har vi i løpet av en 4 års periode (2006-2009) samlet inn kornprøver fra partier med norskprodusert havre og vårhvete med tilhørende opplysninger om klima og dyrkningsmessige forhold. Kornprøvene er videre analysert for innhold av 17 ulike mykotoksiner. Ved å sammenstille og analysere data og informasjon om de ulike kornprøvene, har vi kartlagt ulike faktorer som kan ha betydning for utvikling av mykotoksiner i kornet. Dataene er videre brukt for å utvikle varslingsmodeller for Fusarium-mykotoksiner i korn, og for utprøving av ulike hurtigmetoder som er utviklet for å måle innhold av mykotoksiner i korn.

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CSNN (current season needle necrosis) gjer stor skade på edelgran til juletre og pyntegrønt både i Europa og USA. Nålene vert misfarga og fell ofte av. Det vi veit om CSNN så langt er: Utbrot av CSNN er truleg klimarelatert Stor variasjon i angrep mellom lokalitetar Genetisk variasjon i resistens mot CSNN CSNN skuldast etter alt å døma ikkje Ca-mangel CSNN smittar frå tre til tre Sydowia polyspora (syn. Kabatina abietis) isolert frå nåler med CSNN-symptom Smitteforsøk med S. polyspora gav CSNN-symptom S. polyspora vart funnen på frø S. polyspora isolert frå nåler med øydelagt vokslag rundt spalteopningane Pestalotiopsis funerea gav ikkje CSNN-symptom Dårleg effekt av kjemiske middel mot CSNN   

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The leaf blotch disease complex (LBD) frequently reduces yield of wheat in Norway. In visual assessments field symptoms can be difficult to attribute definitively to specific causal agents, and may be caused by any or all of the following three pathogens: Stagonospora nodorum (teleomorph: Phaeosphaeria nodorum) causing Stagonospora nodorum or glume blotch (SNB), Septoria tritici (teleomorph: Mycosphaerella graminicola) causing Septoria tritici or speckled leaf blotch (STB), and Drechslera tritici-repentis (teleomorph: Pyrenophora tritici-repentis) causing tan spot (DTR). There is no broad resistance to all three pathogens in commercially relevant wheat  varieties. We analyzed 9 years of historical data on severity of LBD in the field and 36 years of historical data on post-harvest SNB infection of wheat kernels. Overall, correlation between leaf severity and seed severity over years was low (r=0.5). However, during the last 4 years correlations between SNB seed infection and severity of LBD increased (r=0.825). LBD severity varied signficantly with geographic location and increased exponentially on the last 3 leaves betweeen BBCH stage 70 and the last assessment at BBCH stage 89. An improved understanding of environmental and host developmental factors as they affect each member fo the LBD complex in the field will be essential to screening for quantitative and durab