Study of the Phenological and Physiological Traits Associated with the Seed Yield in Different Canola (Brassica napus L.) Cultivars

In order to determine the most important phenological traits influencing the increase in seed yield and their relationship with yield and yield components in spring cultivars of canola, a factorial Split plot experiment was conducted based on randomized complete block design with four replications in 2013-2014 growing season in the Research Field of Gonbad Kavous University. Treatments included four canola cultivars (C1= Hyolla401, C2= Zarfam, C3= Hyolla308 and C4= RGS003), two planting dates (D1= 20 November and D2= 30 December) and three levels of nitrogen fertilizer (N1= zero, N2= 50% and N3=100%). The results showed significant differences in seed yield and other traits. The highest yield in the RGS003 (4.4ton ha-1) planted on 20 November and the lowest in Hyolla308 (1.1ton ha-1), were observed using nitrogen fertilizer and in this respect they were divided into three groups: high yielding (RGS003), medium (Hyolla401 and Zarfam) and low (Hyolla308). The maximum seed filling rate (6.1g/day) for the treatment RGS003 and 100% of the recommended nitrogen fertilizer and lowest (3.7g/day) the date of 30 November was Hyo1la 308. In addition, on the date of 30 December, Hyolla308 lowest seed weight (3.52g) with 100% nitrogen fertilizers, and RGS003 had the highest seed weight (4.04g), respectively. Seed yield except in the days to flowering (r=0.70**) and 1000 seed weight (0.19g) had a significant positive correlation with the other traits.