Evaluation of the effect of winter sowing dates on yield and yield components of canola (Brassica napus L.) and mustard (Brassica juncea L.) genotypes in Gorgan area

In order to evaluate the effect of winter sowing dates on yield and yield components of canola (Brassica napus L.) and mustard (Brassica juncea L.), an experiment was conducted at the Agricultural Research Station of Gorgan during 2009. The experiment was a spilt plot design, arranged in an RCBD with 3 replications. Four sowing dates (January 5, 20 and February 5, 20) were main plots and four genotypes Hyola 401, RGS003 (canola) and Bard1 and J98 (mustard) were sub plots. The results showed that delay in sowing date significantly decreased the number of pods per plant, the number of seed per pods, 1000-seed weight and seed yield. First sowing date had the highest seed yield (2407 Kg/ha) and fourth sowing date had the lowest seed yield (1054 Kg/ha). The number of pods per plant in mustard genotypes was more than that of canola genotypes.However the number of seeds per pod, 1000-seed weight and seed yield of canola genotypes were more than those of mustard genotypes. Hyola 401 had the highest number of seeds per pod, 1000-seed weight and seed yield.Based on the results of the experiment when sowing date is delayed and condition is not favorable for autumn sowing it is recommended to sow Hyola 401 in January 5.