Effect of Sowing Date and Glycinebetaine on Seed Yield, Oil Content, and Fatty Acids in Rapeseed Cultivars

This study primarily aimed to identify and suggest appropriate rapeseed cultivars and their optimum sowing time. A factorial split-plot experiment was conducted in a complete randomized block design with three replications during two years (۲۰۱۴-۲۰۱۶). The study was carried out using six rapeseed cultivars, namely, Elvis, HL۲۰۱۲, L۱۵۵, KR۲, HW۱۱۳ and Danob, three sowing dates (October ۷, ۱۷, and ۲۷), and two concentrations of glycinebetaine (۰ as control and ۰.۲%). The sowing dates and the GlycineBetaine (GB) were allotted to main plots and the six cultivars were allotted to subplots. The HL۲۰۱۲ cultivar had the highest seed yield (۴,۵۸۴ kg ha-۱), seed oil content (۴۴.۶%) and seed oil yield (۲,۰۶۰ kg ha-۱), which were achieved optimally in the first sowing date. Application of GB increased the average seed yield from ۴,۰۸۹ to ۴,۴۱۹ (kg ha-۱), seed oil from ۴۴ to ۴۴.۴% and seed oil yield from ۱,۸۱۸ to ۱,۹۷۶ (kg/ha). The amounts of proline and soluble carbohydrates in the plants increased from the first to the third sowing dates. The early sowing date and the application of GB had positive effects on the quantity and quality of rapeseed oil. The results of cluster analysis showed that three of the six cultivars could be suitable for cultivation in Karaj, Iran.

کلیدواژه ها:

Brassica napus L. ، Canola ، Proline ، Rapeseed cultivars ، Soluble carbohydrates.