Does seeding date and rate of canola effect spring flea beetle pressure, yield, and quality?

Term: 1 Year, beginning 2024
Status: Ongoing
Researcher(s): Gursahib Singh, ICDC; Brianne McInnes, NARF; Amber Wall/Bryan Nybo, WCA; Koralie Mack/Jessica Enns, WARC 
SaskCanola Investment: $18,200
Total Project Cost: $35,400
Funding Partners: ADOPT

Objective

 To demonstrate canola yield and quality response to a wide variety of seeding dates in various locations in SK. 

 To demonstrate what seeding date is best for avoiding high flea beetle pressure in canola. 

 To demonstrate if a higher canola seeding rate is a good management strategy to protect yield in the event of heavy flea beetle pressure. 

Project Description

The last several growing seasons have been much drier and warmer than the long-term average throughout most growing regions in Saskatchewan. For instance, in 2023 snow melt was delayed in some regions, however, the melt was rapid and most producers were able to commence field activities by early May in northern regions, and even earlier in southern regions. Some producers in the Northeast region of the province were seeding canola the 1st week of May, which is not usually the case. With no late spring frost and very warm and dry spring and summer conditions this ended up being a relatively smart agronomic decision for some. Depending on the region of the province some areas may see canola being seeded as early as late April when dry spring conditions exist. With limited moisture throughout the growing season in recent years, taking advantage of early season soil moisture is essential for successful crop establishment. 

 According to a recent article in the Western Producer, some farmers are continuing to seed canola in late May even though there are known benefits of seeding early. According to Tyler Wist, an entomologist with Agriculture and Agri-Foods Canda, seeding canola early used to work well to get canola out of the ground before flea beetle populations appeared. Past research recommending early canola seed dates was when crucifer flea beetles were more prevalent; however, striped flea beetles have become more common. According to Tyler Wist, striped flea beetles emerge two weeks earlier in the spring than crucifer, which can now make seeding early less advantageous (The Western Producer 2023). Seeding date for canola should ideally be based on soil moisture conditions and soil temperature rather than a specific date; however, producers are wanting to get the crop in the ground whenever they can manage to do so.  

Knowing that seeding early is best for canola yield and quality, while also considering that seeding early may increase flea beetle pressure on the crop poses conflicting best management practices for canola producers. With tight canola rotations in major growing regions of the province resulting in high flea beetle populations, along with growing concerns of foliar insecticide use, relying on good agronomic decision making is essential. The intended benefit of this demonstration for producers is to show case a wide range of seeding dates in canola, in combination with an adequate and increased seeding rate, so producers can make best management decisions for seeding canola to avoid heavy flea beetle infestations and the need for insecticides, while achieving high yields and best quality.