Study on Rate and Method of Phosphorus Application in Canola Field

In order to determine the best rate and application method of P fertilizer on canola the experiment was carried out in Golpaygan, Kermanshah, Fars, Safi Abad, Khorram Abad, Mazandaran, Bushehr, Khorasan and Iranshahr. Factorial experiment carried out based on randomized complete block design with three replications. The two factors were application rate (0.4R, 0.8R and 1.2R which R was the recommended amount of fertilizer for wheat) and application method (broadcasting and banding). The source of P-fertilizer was Triple Super Phosphate (TSP) and applied before planting. Other fertilizers were used in accordance with the fertilizer recommendations for wheat. Also a control treatment without P-fertilizer was considered. The results in Golpayegan showed that application method had not significant effects, but the rates of application had changed yield significantly. Although the level of 1.25R had the highest yield, but this treatment was not differed significantly with R treatment. Although the main and interaction effects of seed yield were not changed significantly in Kermanshah but the oil percentage affected and the furthest percentage of oil were obtained from 1.25R treatment. The experiment in Darab- Fars was performed in a soil with low Olsen P levels (about 5 mg.kg-1) and the seed yield in 1999-2000 was lower than 2000-01. In the first year of experiment, application of 0.4R and in the second year application of 0.8R as banding or 1.2R as broadcasting had provided the furthest yield compared to other treatments. In other words, application of P-fertilizer as banding decreasd fertilizer requirement relative to broadcast application in second year. In Safi Abad- Dezful we observed that we should appli 2 times more P fertilizer in broadcast methods to get equal seed yield of 0.4R as banding treatment. In Khoramabad, oil yield mean comparison have been shown the highest yield were achieved with the application of 1.25R as broadcasting. In Bushehr, seed yield were increased 6.5% when P-fertilizer applied as banding compared with the broadcasting. Experiments were conducted in three regions (Baie-Kola, Dasht-e- Naz and Firozkandeh) in Mazandaran province. In Baie-Kola highest yield were obtained in the 0.75R, but the difference between the two methods (Banding and Broadcasting) were not changed significantly. In regions Dasht-e- Naz and Firozkandeh, significant changes between treatments were not observed. The same situation was observed in experiment at Bushehr. The experiments in Khorasan province were carried out in Mashhad, Neishabour, Kashmar, Birjand and Gonabad for two years. The results indicated that the treatments were not caused significant changes in yield in Mashhad and Gonabad, but the changes in Nishabur, Kashmar and Birjand were significant. Key words: canola , phosphorous,Ban ding ,Broad cast ,Rate ,Regions