Fatty acid composition of canola cultivars as affected by different sowing dates

To investigate the effect of sowing date on yield and qualitative traits of canola cultivars to cope with late-season drought stress, an experiment was carried out during two planting years in Karaj, Iran. Sowing dates at six levels including three fall and three winter dates were considered as the main factor, and five canola cultivars (RGS003, Dalgan, Zabol10, Hyola 401, and Hyola 4815) were considered as the sub-factors. Results showed that except for palmitic acid, the simple effect of sowing date on all the studied traits was significant in winter. The simple effect of cultivar on all traits in fall was significant, and in winter it was only significant on the seed yield and seed oil yield. The interaction between sowing date and cultivar in fall is the reason for significant effect of seed oil yield, linoleic acid, linolenic acid, erucic acid, and glucosinolate. The same reason holds for the significant difference in seed yield, oil content, oil yield, and erucic acid of the plants sown in winter. Dalgan cultivar had the highest seed yield and oil yield on sowing date of October 7, also with the highest levels of oleic, linoleic, and palmitic fatty acids. Based on the results of this study, Dalhgan cultivar with low and standard erucic acid and glucosinolate is recommended for cultivation in the area.