July 5, 2018 – Issue 14

Sub Categories

  • No categories
  • Top 10 questions from canolaPALOOZA 2018

    canolaPALOOZA 2018 was at AAFC Saskatoon June 25 and AAFC Lacombe June 27. Here are the top 10 questions from the two events.


  • Canola Watch quiz – Insect ID

    Can you identify these four insects?


  • Map of the Week – Cabbage seedpod weevil counts

    Alberta Agriculture’s cabbage seedpod weevil survey results for 2018 are mapped. In areas with a red marker, 25% or more of samples reported are above the threshold.


  • The disease triangle: Moisture means sclerotinia

    The three points of the disease triangle are host, pathogen and environment. When it comes to sclerotinia stem rot in canola in Western Canada, the disease triangle hinges on one component: Environment.


  • Sclerotinia stem rot timeline for infection

    The sclerotinia stem rot infection cycle begins when sclerotia in the soil (left from the last time an infected crop was produced on that field) take up enough moisture to germinate and form little mushrooms known as apothecia. Spores are then released into the air from the mushrooms. Under ideal warm and moist conditions, it takes about two to three weeks for sclerotia to germinate and release spores.


  • Sclerotinia stem rot: Late and second sprays

    If conditions are dry at early flower and then it rains at 40% to 50% flower, spraying at the end of the window may be effective – as long as there was enough moisture before flowering to get apothecia germinating. In this situation, later sprays could be especially effective if moisture also promoted a longer flowering window due to later compensatory growth. With lower seeding rates resulting in more branching, canola fields can be at 50% flower for a week or more.


  • Sclerotinia: Positive petal test may not mean “spray”

    Small amounts of spores can lead to yield-robbing levels of sclerotinia in continued moist conditions. A petal test to confirm the presence of sclerotinia DNA on petals could be used to provide an indication of pathogen pressure at the time of petal collection.


  • Hot weather and flowering. Any treatments?

    Not really. At least nothing shown to work consistently in Western Canada.


  • Hot days and 6 other reasons for missing pods

    Seeing blanks up canola stems where pods should be? Here are the seven most common causes…. At the bottom of this article, see a graph showing how canola plants can compensate for aborted flowers.


  • Lygus bugs: Thresholds and scouting tips

    Lygus. Credit: Dan Johnson

    In very dry conditions: Threshold tables for lygus indicate that if canola is $12 per bushel and spray costs $8 per acre, the threshold at the early pod stage is 5 lygus adults or late instar nymphs per 10 sweeps (0.5 per sweep).

    In moist and high-yield conditions: The economic threshold is quite a bit higher. At early pod stage, 50 lygus per 10 sweeps (5 per sweep) could cause a 2 bu./ac. reduction in yield — which could be a more suitable economic threshold in this situation. At late pod stage (the last week or so before cutting), pods are too tough to penetrate.


  • How late can you top dress fertilizer?

    The ideal time for a sulphur top up is any time before flowering, but a top up at early flowering may pay off if plants are showing signs of sulphur deficiency. The ideal time for a nitrogen top up is before the 5-leaf stage of canola, but AAFC research out of Indian Head, Saskatchewan, shows that nitrogen top dress as late as 5-10% flower can still provide a yield benefit.


  • ‘PALOOZA travels to Portage la Prairie for July 25

    With Saskatchewan and Alberta enjoying highly successful canolaPALOOZAs this week, the attention now turns to Manitoba’s CROPS-A-PALOOZA, July 25 in Portage la Prairie. The one day, hands on, free, in-field learning interactive event brings together the best research and agronomy extension professionals and farmers to learn how to grow the best crops.


Canola Watch