The risk of sclerotinia in parts of southeastern and central Saskatchewan and Manitoba has increased substantially since heavy showers hit July 1 and 2, says a research group tracking the disease.
The soil surface under heavy crop canopy in the areas that got rain will remain moist and favorable for germination of sclerotinia sclerotia and spore release until about July 10.
Petal testing using the DuPont Alert Sclerotinia Test Kit is being done by Manitoba Agriculture staff this week in selected fields to further assess the sclerotinia risk.
Results before the July rain indicated a low presence of sclerotinia spores and mycelium on canola petals, but since then, there is a more positive reaction indicating presence of the fungus.
Factors to consider
The decision whether to apply a fungicide to an individual field for control of sclerotinia should be determined by favorable weather conditions, as well as previous occurrences of the disease in the field, crop rotation and yield potential of the crop.
