Trial Report Summary

Effect of seeding rate and plant growth regulators on Winter Wheat

Crop Type(s):
Winter Wheat

Ken Gross, Ducks Unlimited Canada


Winter wheat varieties have had a 21 per cent higher yield than Canadian Western Red Spring wheat over the past three years in the Prairie Provinces [Western Winter Wheat Initiative]. Return on investment can be more than two times higher than for spring wheat. In addition to providing an effective tool to manage pests, nutrients and moisture, winter wheat can improve crop rotations and distribute cropping activities, enhancing timeliness of operations.

Lodging is a major crop production issue, especially in high yielding winter wheat environments. Lodging can be managed through variety selection and agronomics. Crop varieties vary in their resistance to lodging, with stem length, thickness of stem internodes, root structure, and head density and shape affecting resistance to lodging.

Plant growth regulators (PGRs) are another management tool used to reduce lodging.

PGRs are synthetic compounds that alter hormonal activity to modify plant growth and development. PGRs are used to improve crop standability, as they are intended to produce shorter, thicker, and stronger stems.

Similarly, seeding rate is another important factor that determines winter wheat yield. Yield advantage to higher seeding rates happens because of several factors, and not just because of weed competition. In areas where fusarium is a problem, higher plant populations may mean fewer tillers, which may mean more uniform flowering making a fungicide application more precise to protect both yield and quality.
The objective of this project was to evaluate the effects of different PGRs and seeding rates on winter wheat height, lodging and yield.

Project Findings:

Winter wheat holds an important place in crop rotations on the Canadian prairie. The current study showed that higher seeding rate and use of plant growth regulator, Manipulator did not have any effect on lodging and grain yield. Although this PGR resulted in reduction in plant height but this change was not reflected in yield gain. More work is needed to identify best management practices that can maximize winter wheat yield and increase profitability for producers.


Entire findings are available by downloading the report PDF.

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