The English grain aphid (Sitobion avenae) has started to appear
across the Prairies in various cereal crops this past week so the time to scout
is now. Look for this aphid infesting wheat heads (favourite host) as well as
barley, oat, rye, Timothy and canaryseed.
This aphid can also be a vector for barley yellow dwarf virus. You might
see the green, red colour morph or both morphs in fields this
year (Fig. 1). You will probably also see ladybeetle (@FieldHeroes) adults and larvae hunting the
aphids (Fig. 2). The economic threshold for aphids in spring wheat in Western
Canada is 12-15 aphids per head prior to the soft dough stage.
Agriculture and Agri-Food Canada, with funding from the Pest Management Centre, has developed a smartphone app called Cereal Aphid Manager (CAM) to facilitate scouting for aphids in cereals that also allows you to record the beneficial insects in the field that can keep aphid populations below the economic threshold – available at Apple iTunes and Google Play app stores. CAM information and download links.
Submitted by Dr. Tyler Wist (Tyler.Wist@agr.gc.ca).
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| Fig. 1 Green and red morph English grain aphid (Tyler Wist, AAFC) |
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| Fig. 2 Seven-spotted lady bird larva hunting aphids (Tyler Wist, AAFC) |
