Comparison of Seed Yield and Macro Nutrients Content in Seeds of 15 Winter Rapeseed (Brassics napus L.) Varieties as Affected by Sulphur Utilization

In order to compare the seed yield of 15 winter rapeseed (Brassics napus L.) genotypes, a field experiment were performed in 2006-7 and 2007-8 cropping seasons in Agricultural and Natural Resources Research Center of Markazi Province, Arak, Iran. Rapeseed genotypes were compared in a randomized complete block design with three replications. Means comparison showed that Licord (3795 kg/ha), Modena (3655 kg/ha) and Okapi (3277 kg/ha) genotypes had the greatest seed yield, respectively. In the second phase of this research, in order to evaluate the effects of sulphur (S) rates on seed yield and accumulation of macro nutrient in seeds of high yielding rapeseed genotypes, a field experiment carried out as factorial arrangement based on randomized complete block design with three replications, during 2008-9 and 2009-10 cropping seasons at the same site. Rapeseed varieties includinges of Okapi, Modena and Licord) and three rates of sulphur (0, 40 and 80 kg /ha) comprised the experimental factors. The interaction effect between sulphur*variety were significant for seed yield and other measured traits. The combination of 40 kg/ha Sulphur*Okapi showed the highest seed yield and seed nitrogen content. Greatest seed phosphorus and potassium content was observed in Modena cultivar and S2 treatment (40 kg S/ha). Licord cultivar showed the highest ratio of seed sulphur content at check treatment and different rates of sulphur utilization in comparison with other vareties. In general, it is presumed that utilization of 40 kg S/ha can enhance seed yield and seed macro nutrient content, related to rapeseed genotype.