Project code: J-003187/PRR23-010
Project Leads
Caitlin Watt – Agriculture and Agri-Food Canada
Héctor Carcamo – Agriculture and Agri-Food Canada
Boyd Mori – University of Alberta
Objective
To demonstrate to growers the impacts of insecticide spray and non-spray regimes on insect pests and their natural enemies in alfalfa seed fields.
Alfalfa seed production in southern Alberta is threatened by multiple insect pests, including the alfalfa weevil (Hypera postica), alfalfa plant bug (Adelphocoris lineatus) and various plant bugs (Lygus species). As a perennial crop, alfalfa seed typically faces increasing insect and disease pressures over the years of growth before being terminated. With limited control products available and increasing resistance to pesticides, growers face declining yields and some are choosing to terminate their crops earlier. Further, alfalfa seed growers rely on leaf cutter bees (own operations or outsourced) for pollination and seed production; therefore it is critical that insecticide applications during flowering periods are avoided as much as possible. For effective pest management, alfalfa seed growers need appropriate solutions to consider both acceptable levels of pest control and protection of pollinators and natural enemies of pests.
This project initiated in spring 2023, as part of a larger ongoing project (2023-2028) co-led by University of Alberta and Agriculture and Agri-Food Canada scientists, and funded through Results Driven Agriculture Research and the Alfalfa Seed Commission of Alberta. The larger project aims to update economic thresholds and improve molecular diagnostic methods for detecting parasitism and insecticide resistance in target pest populations. The present project adds a new integrated pest management objective, expanding the scope to include monitoring of beneficial insects (natural enemies of target pests) and examining environmental factors that may impact insect pests in alfalfa seed crops. Commercial fields are set up with sprayed (conventional practices) and unsprayed strips to assess impact of these measures on abundance of pests and beneficials, as well as on plant damage. This project also supports growers outreach and transfer of knowledge about impacts of pest management practices to inform their decision making.
With trials conducted in commercial alfalfa seed fields across southern Alberta, this work reinforces already established grower partnerships by the Alfalfa Seed Commission of Alberta and provides an opportunity to demonstrate to growers the benefits of integrated management approaches by capitalizing on the naturally occurring and introduced populations of beneficial species. Project results will be shared with growers and industry stakeholders through on-farm demonstrations, field days, meetings and publications to transfer the gained knowledge.