Effect of biological phosphorus and Irrigation disruption on biomass, seed yield and protein content of canola (Brassica napus L.)

Abstract:Results of evaluation of irrigation (irrigation disruption at beginning of flowering, end of flowering, grain filling and control) and biological phosphorus (0, 50, 100 and 150 g/ha) on the yield of Brassica napus L. cv. “Hyola 401”, a split plot experiment was carried out based on randomized complete block design with four replications at the research farm of Shahid Beheshti Agriculture College (latitude 38° 51ʹ N and longitude 41° 44ʹ E and 1313 m above sea level) in 2010. Results of ANOVA showed the significant effect of irrigation disruption on 1000 seed weight, and significant interaction effect between irrigation disruptions and phosphorus on seed yield, biomass, protein content, protein yield and Harvest Index (HI) of protein. Means comparisons indicated that the maximum (4.55 g) and minimum (3.25 g) 1000 seed weight belonged to irrigation disruption at the beginning of flowering with 150 and 50 g/ha of biological phosphorus application, respectively. The highest yield of seed (777.58 kg/ha) and protein (189.3 kg/ha), and harvest index of protein (0.52 %) were obtained from irrigation disruption at the end of flowering and 50 g/ha biological phosphorus, and the lowest seed yield (120.87 kg/ha), protein yield (28.58 kg/ha) and harvest index of protein (0.14 %) were obtained from irrigation disruption at the beginning of flowering and without phosphorus. The highest percent of protein (28.26 %) was obtained from irrigation disruption at beginning of flowering without phosphorus and the lowest percent (20.65 %) was obtained at no disruption stage with 150 g/ha phosphorus. Means comparisons showed that the highest biomass (4.007 kg/ha) belonged to normal irrigation with 50 g/ha phosphorus application. The lowest biomass (3.83 kg/ha) belonged to no phosphorus treatment and irrigation disruption at the beginning of flowering stage.