Insects

Swede midge was not detected in canola grown in the Northern Great Plains between 2006 and 2021. Monitoring continues in North Dakota and western Canada to ensure early detection of swede midge if it continues to move northwestwards. The swede midge, Contarinia nasturtii (Kieffer) is…

Wheat stem sawfly larval mortality did not occur between fall and spring sampling periods indicating that populations are not affected by abiotic or biotic factors during the winter. The populations of wheat stem sawfly and its natural enemies varied across fields in southern Alberta. The…

Cabbage seedpod weevil continues to expand across the Prairies, contributing to yield losses of 5 to 30%. Insecticidal control remains the main management strategy despite decades of research into alternative biological and cultural methods of control. The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), is native…

The overall Economic Injury Level was found to be around 9 to 23 Lygus bugs per 10 sweeps using $15.47/bu ($682/tonne) canola prices. However, insecticide trials on farmers’ commercial fields found that yield was protected from Lygus feeding with a foliar insecticide application at the…

Wheat midge parasitism was found to be as high as 71% in the Peace River region of Alberta.  Parasitism was primarily by Macroglenes penetrans, the main parasitic wasp species that attacks wheat midge on the Canadian Prairies.  A parasitic wasp species, Inostemma walkeri, was newly…

A new economic threshold of 36 ± 7 aphids (29 to 43 aphids) per 180 degree sweep was calculated for Saskatchewan lentil, and provides 7 days lead time to arrange insecticidal application. The economic injury level was calculated at 78 ± 14 aphids (64 to…

AC Ultima formed relatively solid stems at lower internodes compared to Pronghorn, although this did not reduce stem cutting by wheat stem sawfly.  Higher seeding rates of both cultivars resulted in lower wheat stem sawfly damage and higher amounts of sawfly parasitism. Little research has…

Bertha armyworm larvae caused over twice as much feeding damage on plants with diamondback moth eggs than plants without. However, bertha armyworm egg laying was not affected when canola plants had diamondback moth eggs. Diamondback moth adults migrate to the Prairies on winds from the…

The alfalfa weevil increased from a minor pest in 2001 to be the principal insect pest of alfalfa in 2014. Its biological control agent Bathyplectes curculionis, a parasitoid wasp, now also occurs in most areas where alfalfa weevil is found on the Canadian Prairies. The…

Research showed no reduction of seed yield for Brassica napus canola at any infestation level of flies or eggs. Root maggots may be more of a perceived than real threat to Prairie canola producers. Recent wet field seasons across much of the Prairie provinces have…

Broflanilide provided consistent protection against wireworm damage in wheat, and also reduced neonate and resident wireworm populations at levels similar to the deregistered lindane but at a far lower dosage per acre. Wireworm has remerged as an insect pest in cereals, corn, potato, and vegetables…

This study validated the nominal economic threshold of 25 per cent defoliation. It also determined significant associations between landscape structure and flea beetle abundance, weather and flea beetle abundance, and plant density and flea beetle damage. As well, two flea beetle predators were confirmed. Flea…

A new species of gall midge, Contarinia brassicola Sinclair (canola flower midge), was identified on the Canadian Prairies in 2017. To date, economic injury to canola has been low, and research has found early seeded canola had higher feeding damage, but still produced optimum yield….

Seed solid-stemmed CWRS and CNHR wheat varieties at 30 to 35 seeds per square foot to maximize stem solidness and reduce the impact of wheat stem sawfly. For hollow-stemmed CWRS varieties and durum wheat, seed at 40 to 45 seeds per square foot. Growing solid-stemmed…

Research in southern Alberta found that canola fields seeded in April were the most susceptible to cabbage seedpod weevil. A new action threshold of 25 to 40 cabbage seedpod weevils per 10 sweeps at early flowering stage was developed. When cabbage seedpod weevil populations were…

Lygus bug and chocolate spot disease can damage faba bean seed. Research found both organisms are widespread in central and southern Alberta. Seed damage occurs independently of each other, and is primarily caused by lygus bug. Seed damage caused by lygus bug (Lygus spp.) or…

Seed at least 40 seeds per square foot (400 seeds per metre square) for optimum yield and wheat stem sawfly management when growing solid- or hollow-stemmed durum wheat varieties. The foundation for reducing yield loss from wheat stem sawfly (Cephus cinctus) in wheat varieties is…