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Pre-harvest is a good time to scout for disease severity. The photo above shows severe sclerotinia infection. This article includes sclerotinia and various other diseases to look for…
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When doing their own disease surveys, growers may find it easier to check crops while swathing. Stop at five random spots in the field while swathing and check 20 standing plants at each spot. This will give you a good idea how much of the field actually had sclerotinia or blackleg or clubroot, for example…
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Pre-harvest is a good time to scout for disease severity. Fields with lots of diseased plants may also be poorer candidates for straight cutting due to the increased shattering risk. Read more for tips on how to identify blackleg, sclerotinia and alternaria…
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If infection rates are high, determine where most of the yield is. If it’s in the healthy plants, then make harvest decisions based on what’s best for the healthy plants. That means swathing at 50% to 60% seed colour change for ideal yield and quality. If most of the yield is in the infected plants, then earlier swathing — at…
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Late or mild infections of aster yellows could lead to poor seed set in normal-looking pods. Stress from aster yellows can also sometimes lead to purpling or may aggravate sunscald…
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It is not surprising that sclerotinia stem rot disease levels differ from field to field even if fields are in close proximity. Sclerotinia disease level is very dependent on the microclimate within the field. Moist growing conditions (ie. frequent rainfall or high humidity or heavy dews) promote disease development but factors that result in moisture-laden canopies can…
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Moisture before and during and following flowering was the biggest factor driving up sclerotinia stem rot infection this year. Moisture as rain or high humidity or dew through the period from two weeks before flowering through early podding has increased the sclerotinia risk considerably, no matter the rotation history of the field. Most regions had these conditions this year. Fungicide…
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Some regions are reporting higher rates of blackleg (shown above) and most regions are seeing sclerotinia stem rot damage. Fungicide is not effective at this stage of the season, but the weeks leading up to harvest are a good time to scout. Its important to know which disease is present in order to plan rotations and varieties for next year…
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In fields badly infected with sclerotinia, swath when the healthiest plants are ready. These plants will provide most of the yield. Swathing early will not preserve seeds in badly infected plants — those seeds are unlikely to mature no matter when you swath…