Research Objective

• To determine if the canola seed size of new hybrid cultivars has an effect on:
  • Canola emergence
  • Yield
  • Quality

Project Description

Recent surveys indicate that approximately half of all western Canadian canola growers have crop densities of less than 40 plants per square metre (about 4 plants per square foot), yet optimal, consistent yields require a minimum of 50 plants per square metre. Adding to stand establishment challenges is that, in recent years, canola seed size has increased substantially with the new hybrid varieties. Large seed means a lower number of seeds per square metre are planted if seeding rate is based just on pounds per acre, and this approach could run the risk of less than 50 plants per square metre.

This three-year study investigated the influence of seed size on seedling emergence, and canola yield and quality. In 2013, direct-seeded experiments were conducted at nine western Canada locations. Four canola seed sizes (1,000-seed weights ranging from 4.0 to 5.7 g) and one unsized treatment (4.4 g average) were seeded at two rates (75 and 150 seeds per square metre). This project looked at the effects of the different seed sizes on canola emergence and early crop biomass (weight), overall yield, and quality of the crop. The results will directly help canola farmers in choosing their seeding rate based on seed weight to have the most effective crop yield and quality. The key result was that seeding rates should be established on 1,000-seed weight, using an online seeding rate calculator or online apps.