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As a rough estimate, the 20% flower or "bloom" stage is when the main stem has around 15 “flowers”. Canola can reach 20% bloom in 4-5 days after first flower…
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Prevalence of sclerotinia stem rot has a direct correlation to above-average moisture. If a field has regular rains or high humidity or both from two weeks before flowering and through flowering, then infection will likely occur. If growers decide to spray, the window for most products is 20-50% flower. Earlier is usually better as early infection on the main stem…
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For fungicide to provide an economic level of blackleg suppression, the crop has to be susceptible to the disease, blackleg incidence and severity must be high (usually due to short canola rotations) and the fungicide has to go on early – cotyledon to 4-leaf stage – before visible symptoms appear…
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Those same moist fields that have delayed spring harvest as well as seeding in central Alberta (and some other regions) also mean more mud clinging to equipment. More mud means more clubroot spores riding along on tires and equipment frames. Though the time crunch is on, knocking off as much mud as possible will reduce clubroot spread. In these conditions,…
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Make sure soil is cleaned off any used equipment recently purchased from areas known to have clubroot. This is good biosecurity practice. Ideally, this should be done at the purchase location before bringing it home…
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Using the same disease resistance genetics over and over causes a shift in pathogen population, which can then overcome the resistance in our varieties – similar to herbicide resistance in weeds. Knowing the resistance genetics used in previous years will allow growers to rotate to a different resistance gene and reduce the blackleg infection within a field. As many as…
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Each Prairie province does its own disease survey most years. The Manitoba Canola Disease Survey has been happening for over 15 years and tracks a variety of diseases. Alberta’s survey the past few years has mainly been focused around monitoring the spread of clubroot. Blackleg results are based on prevalence, incidence and severity — but what do these words mean?…
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Results from the disease survey show increases in sclerotinia stem rot incidence. Blackleg incidence is down from 2015 in Manitoba and Saskatchewan and up in Alberta…
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Disease scouting long after swathing is not usually the most accurate, as saprophytic organisms — those that feed on and break down dead material — move in fast and cloud the identification process. Verticillium is one disease that can be more obvious and easier to identify after cutting a canola crop…