Aster Yellows and Swede Midge – New Threats to Prairie Canola Product

Agronomy Research  Insects 
Start Date
End Date
Principal Investigator
Chrystel Olivier - AAFC (Saskatoon), Julie Soroka - AAFC (Saskatoon)
MCGA Funding
Total Project Funding
External Funding Partners
Alberta Canola, SaskCanola, Canola Council of Canada, Canadian Agricultural Partnership

Research Objective

  • To generate knowledge of factors influencing the biology of two new pests in canola such as:
    • extent of infestation
    • to evaluate yield losses
    • develop forecast warnings
    • identify resistant canola lines to the two pests

Project Description

Aster yellow is a disease spread by insects that significantly reduces canola yield, with incidence as high as 80 per cent in some fields in 2012. The second pest that was the focus of this study, the swede midge, is an insect pest of crucifer crops* that is native to Europe. The purpose of the study was to identify what biological factors will affect these two pests and to create a rating scale for damage sustained by the canola crop. The incidence of both pests had risen since 2012 and therefore researchers wanted to determine how great the infestation of these pests actually was and what the yield losses from fields with infestations amounted to. This information would enable agronomists to forecast warnings for infestation levels and therefore, yield loss. Finally, this study also aimed to identify resistance sources to these two pests in canola.  The study revealed information about yield losses from aster yellows, tentative economic thresholds for leafhoppers, and lifecycle patterns and host preferences of swede midge. The key result was that growers should scout crops for swede midge and leafhoppers and consult with agronomists if either pest or aster yellows are identified. 


*ie. crops that belong to the Brassicae family, such as cauliflower, cabbage, broccoli, etc.

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