Fertilizer Management and Crop Rotation Strategies on Canola and Wheat Yields and Elemental Composition of Seeds

The aim of this study was to evaluate the efficacy of different fertilizer management systems such as organic, chemical and integrated fertilizer systems in increasing total quality and quantity yields of canola and wheat in two rotations included canola-soybean-wheat and canola-wheat. In this experiment, the effects of zeolite incorporation with different organic and chemical fertilizers were investigated on the improvement of yield components, crop yield and nutrient uptake of canola and wheat in Iran during 2014-2018. Two crop rotations of canola-soybean-wheat and canola-wheat provided the whole-plot treatments with nine fertilization management (F-1: urea, F-2: urea + zeolite, F-3: composted manure, F-4: composted manure + zeolite, F-5: urea + composted manure, F-6: urea+ composted manure + zeolite, F-7: urea+ azocompost, F-8: urea+ azocompost + zeolite and F-9: Control) providing the sub-plots. The highest yield of canola and wheat were observed under F-6 and F-8. Embedding soybean in the rotation was not significantly efficacious in increasing canola and wheat yields. Also, soybean did not reduce wheat and canola yield, it could fulfill its own requirements. Elemental composition of seeds in crops was affected by the treatments. Principal component analysis (PCA) perfectly displayed that organic fertilizers, especially composted manure accompanied with the application of 8 ton ha(-1) zeolite and urea (F-6) had the most predominant effect on yield and yield components in both wheat and canola. Crop rotation in the short-term programs might not produce desirable results, but it is expected to see the efficacy of crop rotation in long-term farming practices.