Comparing the effects of integrated and conventional fertilization systems on canola (Brassica napus) yield and chemical properties of soil

آب و خاک

Article 2, Volume 22, Issue 2, May 2008   

Document Type: Research Article

DOI: 10.22067/jsw.v0i22.977

Authors

H. Sabahi^{* 1}; A. Gholavand²; A.M. Modarres Sanavi²; A. Asgharzadeh³

¹Environmental Sciences Research Institute of Shahid Beheshti University

²College of Agriculture of Tarbiat Modarres University

³Soil and Water Research Institute

Abstract

Abstract
To compare the canola yield and chemical characteristics of soil under integrated and conventional fertilization systems, an experiment was conducted in Savadkooh region for 2 years. The fertilizer treatments concluded 0, 50,100, 150, 200 kg.N.ha-1 urea (F0 to F4), 150 kg.N.ha-1 urea + 50 kg.N.ha-1 manure (MF1), 100 kg.N.ha-1 urea + 50 kg.N.ha-1 manure (MF2), 50 kg.N.ha-1 urea + 100 kg.N.ha-1 manure (MF3), 150 kg.N.ha-1 manure (M). The results showed that for both years the highest yield was obtained from integrated system of 150 kg.N.ha-1 urea + 50 kg.N.ha-1 manure (MF1). For the first year no difference between seed yield of integrated and chemical treatments was observed, however, the integrated treatments seed yield was significantly higher than the chemical treatments for the 2nd year. In addition, in organic system (M) yield was lower than inorganic system (F3) for the first year, while this was reversed for the second year. The application of manure increased available phosphorus significantly. For example, in organic system the available phosphorus increased 115% as compared with chemical system. In both systems the organic carbon content increased, but this increase was 12% and 35% for the chemical and integrated systems, respectively. Total nitrogen had a similar trend and the correlation coefficient was very significant (R2=0.93). According to the results it can be concluded that the integrated fertilization can be suggested as a suitable strategy to increase the available phosphorus in soil and to obtain a sustainable yield of canola.

Key words: Manure, Integrated fertilization system, Nitrogen, Phosphorus, Canola, Yield.