Effect of Crop Residue Management and Nitrogen Splitting Methods on Yield and Yield Components of Canola (Brassica napus L.)

(CRM) and N fertilizer on yield and yield components of canola. Field experiment was carried out on Farm Research Station, College of Agriculture at Shahid Chamran University, during 2006-2007 and 2007-2008. Wheat crop was planted in first year and followed by planting canola in second year. The experiment design was a randomized complete block with 3 replications as a split plot. Crop residue management (incorporation, removal and burning of wheat residues) was main plot and N- splitting (the source of nitrogen was 150 kg/ha urea) was subplot including: (1) 50% pre- planting + 50% at twelve leaf stage, (2) 25 % pre- planting + 75% at twelve leaf stage and (3) 25 % pre- planting + 50%at twelve leaf stage + 25 % pre- stem growth. Plant parameters including plant height, peduncle height, pod weight/m2, number of secondary branches, pod length, pod number/m2, seed number/pod, 1000 seed weight, seed yield, biological yield, harvest index, oil percent, protein percent, and oil and protein yield were measured. The findings in the present study showed that yield and yield components have able to perform better when the plants grown on the soil contains incorporation treatment as compared to the other treatments. A highly significant effect was obtained at N- splitting of 25+50+25 when compared to the other N- splits. The highest (4630.5 kg/ha) yield was achieved from the plants sown on the soil receiving 25+75 of N-splitting with incorporation treatment, while the lowest (1964.7 kg/ha) yield was obtained under the burning of residues from the soil having 50+50 of N-splitting. Whereas, the highest oil percent (43.15%) was extracted from seeds of the plants which were grown on the soil receiving 50+50 of N- splitting incorporation treatment and the lowest oil percent (37%) appeared to be gone from seeds of those plants grown on the soil having 25+75 of N- splitting with no residues treatment. In general, incorporation of management technique plus N- splitting exhibited a positive impact on yield and yield components of canola when compared to other treatment.