Effects of Nitrogen and Sulphur Different Levels and Sources on Yield, Nutrients Concentration and Oil Content of Canola(Brassica napus L.)

Nitrogen and sulfur are the most effective nutrients in oil seed production, especially, canola. In order to study the effects of different levels of nitrogen and sulphur on seed yield, yield components, seed oil, and leaf and seed nutrients content of canola (Brassica napus L.) a factorial experiment was carried out in a randomized complete block design with eight treatments and three replications for two years. The first factor consisted of two nitrogen levels (N1=180 and N2=240 kg. ha-1 net nitrogen) and second factor had four sulphur levels (S0=0, S1=200 kg ha-1 powder sulphur inoculated with Thiobacillus inoculant, S2=100 kg ha-1 from ((NH3)2SO4 and S3=100 kg ha-1   from CaSO4). The results showed that effect of the nitrogen levels were significant on leaf nitrogen concentration, and seed nitrogen concentration and uptake at 0.01-probability level and seed sulphur at 0.05 probability level but was not significant on other measured attributes. Effect of the sulphur levels were significant on leaf sulphur concentration, seed and oil yield and seed sulphur concentration and uptake at 0.01 probability level and leaf nitrogen and seed oil concentration at 0.05 probability level. The maximum seed and oil yield, seed nitrogen and sulphur uptake, leaf sulphur and seed oil concentration were obtained from S1 level with 5069, 2135, 99.5 and 23.3 kg per ha and 0.95 and 42.1 percent, respectively. The two way interactions of nitrogen and sulphur were significant on leaf and seed nitrogen concentration. In general, the application of 180 kg nitrogen and 200 kg inoculated sulphur with two percent Thiobacillus inoculant would be recommended to achieve the optimum growth of canola in similar soils.