65 research outputs found

    Use of cultivar resistance and crop rotation with Bacillus subtilis for clubroot control in canola

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    Non-Peer ReviewedThis study was conducted to assess additional strategies potentially complimentary to cultivar resistance or biocontrol in control of clubroot. New granular Bacillus subtilis formulations and a seed dressing method were developed to facilitate biofungicide delivery in field trials. The granular formulations were applied in furrow during seeding at 50 kg/ha to a clubroot resistant (CR) and susceptible (CS) canola cultivar, respectively, in three field trials. The seed dressing applied approximately 1×105 to 5×106 cfu/seed doses of the biocontrol agent, and was evaluated on the CS cultivar seeded to different crop-rotation scenarios where the plots had a 1-year, 3-year, or 11-year break from last canola crop. Clubroot disease pressure was high at all trial sites with disease severity indexes (DSI) ranging from 69% to 98% on the CS cultivar. None of the granular formulations reduced clubroot substantially, whereas the CR cultivar showed a high effect, reducing DSI to below 15% and doubling the yield over that of CS cultivar. Plots of varying rotation showed a pattern of clubroot pathogen pressure, with those of 1-year break from canola being the highest. The DSI for all rotational scenarios was high, reaching 100% in short-rotation plots. Biofungicide seed dressing did not reduce DSI, but longer crop rotation often reduced gall size slightly, showed much milder above-ground damage, and increased the yield significantly relative to short rotation in two separate trials. Even a 3-year break from canola was highly beneficial, with the yield doubled as opposed to that with only 1-year break from canola

    Causes and consequences of unexpected educational transitions in Switzerland

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    The present study examines transition patterns of Swiss secondary and tertiary school students. Switzerland's highly canalized education system allows us to test how tracking affects person-environment fit of students for students who choose a normative versus unexpected downward transition pattern. In addition, we investigate how self-efficacy expectations and personal values affect an unexpected transition choice. Results indicate that students with strong expectancies and personal values can oppose institutional norms and chart their own academic course; however, these students are less likely to perceive a good fit between their own interests and competencies and institutional demands after the transition. Our findings underscore the importance of developmentally appropriate educational environments and systems permeable enough to adapt to developing students' changing interests
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