Canola Response to Sulfur and Nitrogen Fertilization.

Canola (Brassica napus L.) production is a major crop in Western Canada.  In the province of Quebec (Canada), only a small area of spring canola is seeded each year.  It is well known that sulfur and nitrogen fertilization improves grain yield of canola in the Canadian prairies.  In Quebec (Canada), it is generally recommended to apply 80-120 kg N ha^-1 with no specific recommendation for sulfur fertilization.  An experiment was conducted during 3 years (2012-2014) at the Agriculture and Agri-Food Canada research farm (Normandin, Quebec, Canada: 48^o51’ N, 72^o32’ W).  Four Nitrogen (N) rates (50, 100, 150 and 200 kg ha^-1) and three Sulfur (S) rates (0, 20 and 40 kg ha^-1) were evaluated each year.  The interaction N x S was not significant for all the traits (grain yield, oil content, N and S content in seed) measured during the 3 years.  The effect of N fertilization on grain yield was significant in 2012 only.   An application of 200 kg N ha^-1 increased the grain by 14 %.  Nitrogen fertilization increased protein content in seed (2013 and 2014) but decreased oil content.  Sulfur fertilization increased grain yield during the 3 years.  In conclusion, the impact of nitrogen fertilization compared to sulfur was less important. Sulfur fertilization up to 20 kg ha⁻¹ improved both seed yield and oil content of canola. In some areas of eastern Canada, a specific attention should be made to avoid sulfur deficiency in canola.