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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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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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Net blotch, caused by the necrotrophic fungus Pyrenophora teres, is one of the major diseases in barley in Norway causing quantitative and qualitative yield losses. Resistance in Norwegian cultivars and germplasm is generally insufficient and resistance sources have not been extensively explored yet. In this study, we mapped quantitative trait loci (QTL) associated with resistance to net blotch in Nordic germplasm. We evaluated a collection of 209 mostly Nordic spring barley lines for reactions to net form net blotch (NFNB; Pyrenophora teres f. teres) in inoculations with three single conidia isolates at the seedling stage and in inoculated field trials at the adult stage in 4 years. Using 5669 SNP markers genotyped with the Illumina iSelect 9k Barley SNP Chip and a mixed linear model accounting for population structure and kinship, we found a total of 35 significant marker-trait associations for net blotch resistance, corresponding to 13 QTL, on all chromosomes. Out of these QTL, seven conferred resistance only in adult plants and four were only detectable in seedlings. Two QTL on chromosomes 3H and 6H were significant during both seedling inoculations and adult stage field trials. These are promising candidates for breeding programs using marker-assisted selection strategies. The results elucidate the genetic background of NFNB resistance in Nordic germplasm and suggest that NB resistance is conferred by a number of genes each with small-to-moderate effects, making it necessary to pyramid these genes to achieve sufficient levels of resistance.

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Barley net blotch caused by the necrotrophic fungus Pyrenophora teres is a major barley disease in Norway. It can cause grain shriveling and yield losses, and resistance in currently grown cultivars is insufficient. In this study, a set of 589 polymorphic SNP markers was used to map resistance loci in a population of 109 doubled haploid lines from a cross between the closely related Norwegian cultivars Arve (moderately susceptible) and Lavrans (moderately resistant). Resistance to three net form net blotch (P. teres f. teres) single spore isolates was evaluated at the seedling stage in the greenhouse and at the adult plant stage under field conditions during three years. Days to heading and plant height were scored to assess their influence on disease severity. At the seedling stage, three to four quantitative trait loci (QTL) associated with resistance were found per isolate used. A major, putatively novel QTL was identified on chromosome 5H, accounting for 23±48% of the genetic variation. Additional QTL explaining between 12 and 16.5% were found on chromosomes 4H, 5H, 6H and 7H, with the one on 6H being race-specific. The major QTL on 5H was also found in adult plants under field conditions in three years (explaining up to 55%) and the 7H QTL was found in field trials in one year. Additional adult plant resistance QTL on 3H, 6H and 7H were significant in single years. The resistance on chromosomes 3H, 5H, 6H and 7H originates from the more resistant parent Lavrans, while the resistance on 4H is conferred by Arve. The genetic markers associated with the QTL found in this study will benefit marker-assisted selection for resistance against net blotch.

Sammendrag

Det er per i dag påvist resistens eller nedsatt følsomhet mot kjemiske plantevernmidler hos flere skadedyr, plantepatogener og ugras i norske jord- og hagebrukskulturer. Hos skadedyr er resistens mot pyretroider og nedsatt følsomhet for tiakloprid vanlig hos rapsglansbille i oljevekster. Resistens mot pyretroider er påvist hos ferskenbladlus og potetsikade fra potet, gulrotsuger fra gulrot, ferskenbladlus fra persille, kålmøll og ferskenbladlus fra kålvekster, jordbærsnutebille fra jordbær, og ferskenbladlus, bomullsmellus, veksthusmellus og sør-amerikansk minerflue fra veksthus. Det er også funnet resistens mot pirimikarb hos ferskenbladlus og nedsatt følsomhet for imidakloprid hos ferskenbladlus og bomullsmellus. I jordbær og bringebær er det indikasjoner på begynnende resistensutvikling mot flere av middmidlene. Hos plantepatogener er resistens mot QoI-fungicider påvist hos gråskimmel fra jordbær, bringebær og gran i skogplanteskoler, hos mjøldoggsopper i jordbær og veksthusagurk, og hos bladflekksopper i hvete. Resistens mot triazoler er funnet i flere bladflekksopper i hvete. Resistens mot hydroksyanilid- og SDHI-er utbredt hos gråskimmel fra jordbær og bringebær, og i skogplanteskoler er det påvist resistens mot tiofanater.....

Sammendrag

Researchers in plant pathology and entomology often study the interaction between a host plant and its pathogen or an insect pest separately. Although studying single pathogen or insect interactions with a host plant is critical to understand the basic infection processes and to model each disease or pest attack separately, this is an extreme simplification of nature’s complexity, where multiple pests and pathogens often appear in parallel and interact with each other and their host plant. Effective management of pests and diseases require understanding of the complex interaction beteween diseases and pests on the host. Under natural conditions, wheat plants are subjected to attack by several insects and pathogens simultaneously or sequentially. The Bird cherry-oat aphid (Rhopalosiphum padi) and the necrotrophic pathogen Parastagonospora nodorum (syn. Stagonospora nodorum) the causal agent of Stagonospora nodorum blotch (SNB) are economically important pests of wheat in Norway. Since they colonize a common host, they may interact directly through competition for resources or indirectly by affecting the host response either positively (induced resistance) or negatively (induced susceptibility or biopredisposition). The effect of aphid infestation on P. nodorum infection and development of the disease could be an important factor in predicting SNB epidemics. However, studies on this multitrophic interactions are scarce. We conducted controlled greenhouse experiments to study the effect of aphid infestation on subsequent SNB development. The wheat cultivar ‘Bjarne’ was treated as follows:1) Aphid infested + insecticide sprayed + P. nodorum inoculated; 2) Insecticide sprayed + P. nodorum inoculated; 3) Water sprayed + P. nodorum inoculated; 4) Control plants (without aphid, insecticide or P. nodorum). When plants were at ca. BBCH 37, 18 adult female aphids (R. padi) were released per pot (treatment 1). Aphid inoculated plants were kept in an insect proof cage in a greenhouse compartment at 20°C, 70% RH, and 16 h photoperiod. Plants for the other treatments were kept in separate insect proof cages in the same greenhouse. Ten days after aphid release, plants infested with aphids (treatment 1) were sprayed with the insecticide BISCAYA (a.i. thiacloprid) at recommended concentration to remove aphids. Plants in treatment 2 and 3 were sprayed with the insecticide and water, respectively. Twenty-four hours after application of the insecticide or water, plants in treatment 1, 2, and 3 were inoculated with P. nodorum spore suspension (106 spores ml-1). The experiment included three replicates and was repeated two times. SNB incidence and severity were recorded. SNB incidence and severity were significantly higher on aphid infested plants than on non-infested plants (P < 0.05). Ten days after P. nodorum inoculation, disease severity were about 3-fold higher on aphid infested plants (treatment 1) than on non-infested plants (treatment 2 and 3). Plants in the blank control (treatment 4) were free of aphids and showed no symptoms of SNB . Infestation of wheat plants by the bird cherry-oat aphid prior to fungal inoculation enhanced the severity of SNB. P. nodorum is a necrotrophic pathogen that lives on nutrients from disintegrated plant cells. The increase in severity of SNB on aphid infested plants could be due to the increased number of dead or dying cells around the aphids feeding sites. However, whether aphids activity induced local or systemic susceptbility to plants is not yet known and needs to be studied further.

Sammendrag

The necrotrophic fungus Drechslera teres causes net blotch disease in barley by secreting necrotrophic effectors (NEs) which, in the presence of corresponding host susceptibility factors (SF), act as virulence factors in order to enable host colonization. At present the resistance within most Norwegian cultivars is insufficient. This study aims at detecting QTL associated with resistance and susceptibility in the Nordic barley breeding material and at discovering new NE _ SF interactions. This knowledge together with an understanding of the genetic background of the Norwegian net blotch population will be utilized to speed up resistance breeding. Resistance of a segregating mapping population of a cross between the closely related Norwegian varieties Arve and Lavrans to three Norwegian D. teres isolates was assessed at seedling stage in the greenhouse and in adult plants in the field. QTL mapping revealed four major QTL on chromosomes 4H, 5H, 6H and 7H. The 5H and 6H QTL accounted for up to 47% and 14.1% of the genetic variance, respectively, and were found both in seedlings and adult plants with the latter QTL being an isolate-specific association. The high correlation of seedling and adult resistance (R2=0.49) suggests that components of adult plant resistance can be predicted already at the seedling stage. Selected isolates and their culture filtrates will be screened on selected barley lines to characterize novel NE - SF interactions and to map the corresponding sensitivity loci. Effector protein candidates will be purified and further analysed to verify their effect on disease development. Additionally, 365 Norwegian D. teres isolates and a selection of globally collected isolates are currently being ddRAD genotyped in order to obtain SNP markers to study the genetic diversity and population structure of the current Norwegian fungal population. This data will also allow us to perform Genome Wide Association Studies (GWAS) to identify potential novel NE genes.

Sammendrag

Net blotch is a major barley disease in Norway caused by the necrotrophic fungus Drechslera teres leading to yield losses of up to 40%. At present, resistance of Norwegian cultivars is insufficient. The pathogen secretes necrotrophic effectors (NEs) which act as virulence factors in order to gain entry into and nutrients from the host (Liu et al., 2014). NEs cause a hypersensitive response in the presence of corresponding dominant host susceptibility factors. In this study we examine the potential role of NEs and host receptors in explaining susceptibility to net blotch in Norwegian barley. This knowledge together with an understanding of the genetic background of the Norwegian net blotch population will be utilized to speed up resistance breeding. 365 Norwegian D. teres isolates collected from various regions and years, together with a selection of globally collected isolates, will be RADtag genotyped in order to obtain GBS markers to study the genetic diversity, genomic evolution and population structure of the current Norwegian fungal population and to compare it to pathotypes from other countries. Additionally, this data will allow us to perform Genomewide Association Studies (GWAS) to identify potential novel NE genes. Selected isolates and their culture filtrates will be screened for specific reactions against an association mapping panel of ca. 200 mostly Norwegian barley lines and a biparental mapping population (both genotyped with the Illumina barley 9K chip) to characterize novel NE-host susceptibility interactions and to map the corresponding sensitivity loci. Effector protein candidates will be purified and further analysed to verify their effect on disease development.

Sammendrag

Net blotch is a major barley disease in Norway caused by the necrotrophic fungus Drechslera teres leading to yield losses of up to 40%. At present, resistance of Norwegian cultivars is insufficient. The pathogen secretes necrotrophic effectors (NEs) which act as virulence factors in order to gain entry into and nutrients from the host (Liu et al., 2014). NEs cause a hypersensitive response in the presence of corresponding dominant host susceptibility factors. In this study we examine the potential role of NEs and host receptors in explaining susceptibility to net blotch in Norwegian barley. This knowledge together with an understanding of the genetic background of the Norwegian net blotch population will be utilized to speed up resistance breeding. 365 Norwegian D. teres isolates collected from various regions and years, together with a selection of globally collected isolates, will be RADtag genotyped in order to obtain GBS markers to study the genetic diversity, genomic evolution and population structure of the current Norwegian fungal population and to compare it to pathotypes from other countries. Additionally, this data will allow us to perform Genomewide Association Studies (GWAS) to identify potential novel NE genes. Selected isolates and their culture filtrates will be screened for specific reactions against an association mapping panel of ca. 200 mostly Norwegian barley lines and a biparental mapping population (both genotyped with the Illumina barley 9K chip) to characterize novel NE-host susceptibility interactions and to map the corresponding sensitivity loci. Effector protein candidates will be purified and further analysed to verify their effect on disease development.

Sammendrag

In Europe there is an on-going process on implementing regulations aimed at reducing pollution from agricultural production systems, i.e. the Water Framework Directive and the Framework Directive for Sustainable Use of Pesticides. At the same time, there is an increasing focus on food security possibly leading to continued intensification of agricultural production with increased use of external inputs, such as pesticides and fertilizers. Application of sustainable production systems can only be achieved if they balance conflicting environmental and economic effects. In Norway, cereal production is of large importance for food security and reduction of soil and phosphorus losses, as well as pesticide use and leaching/runoff in the cereal production are of special concern. Therefore, we need to determine the most sustainable and effective strategies to reduce loss of top soil, phosphorus and pesticides while maintaining cereal yields. A three-year research project, STRAPP, is addressing these concerns. A catchment area dominated by cereal production is our common research arena within STRAPP. Since 1992 a database (JOVA) with data for soil erosion, nutrient and pesticide leaching/runoff (i.e. concentrations in stream water), yield, and agricultural management practices (fertilization, use of pesticides, soil tillage and rotations) has been established for this catchment allowing us to compare a unique diversity in cropping strategies in a defined location. An important part of STRAPP focuses on developing ‘best plant protection strategies’ for cereal fields in the study area, based on field inventories (manual and sensor based) of weeds and common diseases, available forecast systems, and pesticide leaching risk maps. The results of field studies during the growing seasons of 2013 and 2014 will be presented, with a focus on possible integrated pest management (IPM) strategies for weeds and fungal diseases in cereal production. We will also present the project concept and methods for coupling optimized plant protection strategies to (i) modelling of phosphorus and pesticide leaching/runoff, as well as soil loss, and (ii) farm-economic impacts and adaptations. Further, methods for balancing the conflicting environmental and economic effects of the above practices, and the evaluation of instruments for increased adoption of desirable management practices will be outlined.

Sammendrag

Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.

Sammendrag

Leaf blotch diseases in wheat can cause yield losses above 30 %. The necrotrophic fungus Parastagonospora nodorum is the dominating leaf blotch pathogen in Norwegian spring wheat. It has been well documented at the seedling stage that the pathogen produces necrotrophic effectors (NEs) which induces cell death in plants carrying susceptibility genes (Snn), allowing the necrotroph to enter. However, the role of these interactions under field conditions is less researched. In this study, we conducted field experiments with bi-parental and association mapping populations of spring wheat, to investigate the role of NE/Snn in adult plant resistance. The populations have been genotyped with the Illumina 90 K SNP chip, P. nodorum has high genetic diversity and both sexual and asexual reproduction, but the actual adaptation of the pathogen population to cultivars with different levels of resistance is not well studied. We are screening a collection of Norwegian isolates from known host sources to look for differences in NE-frequencies and haplotype distribution. The mapping populations are also inoculated and infiltrated with culture filtrates from single isolates on the seedling stage. Isolates involved in novel interactions will be deepsequenced in order to look for candidate effector genes. Potential effector proteins will be purified by LPC and HPLC to confirm their role in disease development.

Sammendrag

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.

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.

Sammendrag

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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Bladsjukdommer i norsk hvete


Vi har sett en alarmerende skift i balansen av sopp patogene i de siste 3 årene. Bladsjukdommer kan redusere hveteavlinger betydelig. Soppsjukdommer på hveteblader inkluderer hveteaksprikk, hvetebladprikk, hvetebrunflekk, mjøldogg, og i de siste årene, gulrust. Vi har dokumentert at hveteaksprikk har vært den dominerende arten på hveteblader fra 2005 til 2014, men vi vet fra andre europeiske land at dominerende sopparter kan skifte raskt over tid. Hveteaksprikk har forsvunnet fra Sverige, Danmark, Tyskland og Stortbritania i løpet av de siste 20 år og ble erstattet av hvetebladprikk. Ulike sopper behøver ulike tiltak.  Med hensyn til optimal bruk av plantevernmidler og resistensforedling er det avgjørende å vite hvilke sopparter vi har og hvilke arter vi kan forvente i framtiden. Vi ønsker å gjennomføre en systematisk kartlegging av de ulike sopparter på høst- og vårhveteblader over to år. Samtidig skal vi sammenstille ulike dyrkningsfaktorer som jordtype, hvetesort, jordarbeiding og næringsstoffnivå av planter fra de samme åkrene for å bestemme mulige faktorer som kan påvirke hvilke bladsjukdommer vi kan forvente i framtidig hvetedyrking. Basert på resultatene skal vi utvikle anbefalinger for optimale dyrkningsstrategier for ulike områder.

Active Updated: 11.01.2017
End: des 2018
Start: jan 2017