Oil Yields of Canola as Affected by Nand S Levels and Methods of Application Under Rainfed Conditions

Field experiments were conducted at Cereal Crops Research Institute Pirsabak Nowshera, Pakistan, for two years (2003-04 and 2004¬05) to evaluate the effect of nitrogen and sulfur levels, and methods of nitrogen application on canola (Brassica napus L. cv. Bulbul- 98) under rainfed conditions. In the experiments four levels of S (0, 10, 20, and 30 kg ha-1) and three levels of N (40, 60, and 80 kg ha-1) and a control treatment with both nutrients at zero level were included. Sulfur levels were applied at sowing while N levels were applied by three methods (100 % basal, 90 % basal + 10 % foliar, and 80 % basal + 20 % foliar). The experiments were laid out in RCB design with factorial arrangement having four replications. Results indicated that biological yield and HI were increased significantly with the application of up to 10 kg S ha-1 but no significant increase in these parameters were recorded when S level was increased beyond 10 kg ha-1. Oil yields were enhanced up to 20 kg S ha-1. Plots with highest N level of 80 kg ha-1 had highest values for biological yield (7.37 t ha-1) and oil yield (685 kg ha-1). Nitrogen levels did not affect harvest index. No significant influence of the methods of N application was recorded on any parameter under study. Higher biological and oil yields were recorded during 2004-05 as compared to 2003-04.