1,083 research outputs found

    Leaf stripe resistance of spring barley cultivars

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    Results of six years of screening trials clearly indicate that effective resistance against barley leaf stripe is available, also in modern cultivars. Among the spring barley cultivars that are currently most widely grown in Denmark, Cabaret, Troon, Sebastian, Justina and Brazil appear most resistant, but only Brazil combines a favourable resistance performance (= low mean and standard deviation of environment-adjusted leaf stripe incidence) with a high number of observations (= years of testing). However, the cultivars appearing most resistant over the years are relatively old ones such as Vada, Alabama, Odin and particularly Scarlett, which has been resistant in all years in which it was tested. Amongst the new cultivars, Marigold, Native and SW Immer appear to have the most promising resistance properties so far. However, they have only been tested in two years of which only one had reasonably high infection levels. The results furthermore indicate huge year-to-year variation in infection levels, presumably due to variation in environmental conditions related to leaf stripe infection

    High damage potential of seed-borne spot blotch in organically grown spring barley in Denmark

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    Spot blotch of barley (Bipolaris sorokiniana, perfect state: Cochliobolus sativus) occurs wherever barley is grown but is normally not considered a major problem in Danish barley production. It is therefore not included in routine disease surveys or official variety testing in Denmark. However, recommended seed contamination thresholds are 30% for spring barley and 15% for winter barley. Several spring barley varieties were grown under organic (no seed dressing, mechanical weeding) and conventional (seed dressing with fungicides, herbicide application) production conditions at three sites in Denmark in 2003. The harvested seeds were analysed for contamination levels of seed-borne B. sorokiniana using a blotter method. The percentage of seeds contaminated with B. sorokiniana ranged from about 5 to 95 % and was highly depending on the site, production system and variety. Contamination levels of organically cultivated plots were about twice as high as those of plots receiving conventional treatments. The germinating ability of seeds was highly affected by the level of B. sorokiniana contamination and declined drastically at contamination levels above 60%. This effect appeared to differ among varieties. The 1000-grain weight was not affected by the level of spot blotch contamination of seeds. The results indicate that the importance of spot blotch may be underrated, especially in organic barley production and that the role of varietal resistance should be investigated. More results are expected from ongoing seed analyses

    Reddit news fandoms as digital news literacies: structuring the evaluation of information sources in a challenging information ecosystem

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    Journalism is in crisis. There is consensus that this crisis is driven by four principal factors -- the overcrowded media sphere, the failing funding model of news, declining trust in media, and growing partisanship among news audiences -- yet there is little agreement about how to correct the course, but journalism's relationship to its audience is at the heart of the solution (Nelson, 2021). Digital environments, such as social media site Reddit, offer a unique opportunity to explore the relationship between journalism and its audience as these environments also complicate that relationship. Reddit offers a visible look at the discursive labor of journalists and their audience as they apply their news literacies to work for journalism as critics, boundary makers, and fans. This discourse analysis explores the meaning making work of journalists and news audiences engaging in Ask Me Anything (A.M.A.) discussions on Reddit's World News board. Findings indicate that the hyperliterate news fans on World News generate surprisingly traditional boundaries around journalism that rely heavily on normative expectations of journalism. This study complicates notions of how cultural capital is gained and expressed online and furthers knowledge and understanding of news fandoms and news literacies in action.Includes bibliographical references

    Resistente bygsorter begrænser problemer med bladplet i økologisk såsæd

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    Seed born net blotch is a threat to the organic barley seed production in Denmark because it often exceeds the legal 15% infestation threshold in organically produced barley seed lots. Relationships among initial seed infestation levels, disease development during the growing season, yield parameters and net blotch infestation of the harvested grains were examined. Highly significant positive correlations among initial seed infestation, primary infection of seedlings and disease severity during the growing season as well as among disease severity at flowering and infestation of the harvested grains were found. The seed infestation level was much less than proportionally related to the primary infection of seedlings and to the disease severity later in the season. All these variables were negatively correlated with single grain weight, fraction of large grains and total yield. Varietal resistance appeared to be a key determinant for disease severity and seed infestation. The results will be used to help develop more flexible net blotch infestation thresholds for organically produced barley seeds

    Nanoconfinement-enhanced conformational response of single DNA molecules to changes in ionic environment

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    We show that the ionic environment plays a critical role in determining the configurational properties of DNA confined in silica nanochannels. The extension of DNA in the nanochannels increases as the ionic strength is reduced, almost tripling over two decades in ionic strength for channels around 100x100 nm in dimension. Surprisingly, we find that the variation of the persistence length alone with ionic strength is not enough to explain our results. The effect is due mainly to increasing self-avoidance created by the reduced screening of electrostatic interactions at low ionic strength. To quantify the increase in self-avoidance, we introduce a new parameter into the de Gennes theory: an effective DNA width that gives the increase in the excluded volume due to electrostatic repulsion

    Measurements of Forbush decreases at Mars: both by MSL on ground and by MAVEN in orbit

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    The Radiation Assessment Detector (RAD), on board Mars Science Laboratory's (MSL) Curiosity rover, has been measuring ground level particle fluxes along with the radiation dose rate at the surface of Mars since August 2012. Similar to neutron monitors at Earth, RAD sees many Forbush decreases (FDs) in the galactic cosmic ray (GCR) induced surface fluxes and dose rates. These FDs are associated with coronal mass ejections (CMEs) and/or stream/corotating interaction regions (SIRs/CIRs). Orbiting above the Martian atmosphere, the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft has also been monitoring space weather conditions at Mars since September 2014. The penetrating particle flux channels in the Solar Energetic Particle (SEP) instrument onboard MAVEN can also be employed to detect FDs. For the first time, we study the statistics and properties of a list of FDs observed in-situ at Mars, seen both on the surface by MSL/RAD and in orbit detected by the MAVEN/SEP instrument. Such a list of FDs can be used for studying interplanetary CME (ICME) propagation and SIR evolution through the inner heliosphere. The magnitudes of different FDs can be well-fitted by a power-law distribution. The systematic difference between the magnitudes of the FDs within and outside the Martian atmosphere may be mostly attributed to the energy-dependent modulation of the GCR particles by both the pass-by ICMEs/SIRs and the Martian atmosphere

    From Industry 4.0 to Smolt 4.0 - Current Status, Industry Challenges and Directions for Optimized and Sustainable Production

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    The recent growth and development in salmon farming in Norway has led to a need for more robust and larger smolt/post-smolts. New and larger smolt production plants have been constructed to serve this need. However, these plants are still mainly run through manual labor, meaning that operations and management efficiency strongly depends on the experience of the farmers. This may effectually restrict the desired production growth. To enable the future sustainable growth of the industry, it is necessary to move from the experience-based production regime to knowledge-based and more objective methods. One way of achieving this is to implement solutions based on Industry 4.0 concepts. This paper outlines how Industry 4.0 can be adapted to smolt production through the Smolt 4.0 concept by targeting and analyzing the state-of-the-art within production methods in the smolt industry and evaluating how operations can be improved using Industry 4.0 principles. Three case studies demonstrating how this can be achieved are presented. The study concludes by discussing how more automation and autonomy in smolt facilities can counter challenges related to fish welfare, personnel risks, productivity, and profit
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