Effect of seeding date on winter canola (Brassica napus L.) yield and oil quality in southern Ontario

Abstract

Winter canola or winter oilseed rape (Brassica napus L.) is not commonly grown in Canada. While winter oilseed rape is the dominant growth form in Europe, Canadian canola production is dominated by spring types in western Canada. Research conducted in the 1980s indicated that the environmental conditions in southern Ontario are well suited to the production of winter canola. Since then, however, interest in the crop has ebbed and little to no research has been conducted on the agronomic issues that potentially limit its adoption in the province. The objective of this research was to identify an optimal seeding date for winter canola in southern Ontario. Three winter canola hybrids were evaluated across five seeding dates ranging from early September to late October. Results established the first two weeks of September as the optimal seeding period for winter canola in southern Ontario. Seeding winter canola during this period, such that greater than 600 GDD could be accumulated before the first fall frost, not only reduced winterkill to approximately 20% but also maximized yield potential and ensured optimal oil quality. Winter canola showed great potential for production in southern Ontario and its addition to current crop rotations would diversify and enhance crop production practices in this portion of the province.

Factors Affecting the Quality of Canola Grains and Their Implications for Grain-Based Foods

“…Agronomic practices, including seed selection, sowing date, plant density, fertilization, irrigation, disease and pest control, and harvesting, influence canola grain quality [61,77,[84][85][86]. They can impact the yield, oil content, fatty acid composition, protein content, GSL content, and chlorophyll content of canola grains [85,[87][88][89][90].…”

“…Agronomic practices, including seed selection, sowing date, plant density, fertilization, irrigation, disease and pest control, and harvesting, influence canola grain quality [61,77,[84][85][86]. They can impact the yield, oil content, fatty acid composition, protein content, GSL content, and chlorophyll content of canola grains [85,[87][88][89][90]. Cultivars differ in oil content, protein levels, disease resistance, and other traits that can affect seed quality [86]; thus, choosing a canola cultivar suitable for the growing region is critical.…”

“…The sowing date of canola affects the exposure of the crop to different weather conditions during its growth cycle, which may have an impact on grain yield and quality [91]. Canola should be planted at the optimal time for the local climate to maximize seed yield and quality [85]. For example, early seeding can improve canola emergence, reduce the risk of heat stress during flowering and seed filling, and increase the oil content and fatty acid composition and yield of canola grains [93,94].…”

Modelled Climate Change Impacts on Spring Canola Production Across British Columbia, Canada

“…This is due to canola being an annual crop with a short growth cycle, alongside it being planted in both spring months and winter months (referred to as spring and winter canola respectively) and thus, being grown across the entire calendar year (Daun, 2011). Within Canada specifically however, spring planted canola dominates production -due to the extremely harsh conditions of Canadian winters threatening the growth of a mildcondition crop such as canola (Page et al, 2021).…”