Efficacy of integrated fertilizer management to improve agronomic and physiological traits of canola cultivars

The effects of integrated chemical and organic fertilizers on quantitative, qualitative and physiological traits of two canola cultivars were studied in East Azerbaijan Research Center for Agriculture and Natural Resources, Iran, during 2011 and 2012 growing seasons. The first factor comprised six levels of fertilizers including organic, chemical, and their combination and the second factor was two canola cultivars. Fertilizer treatments had significant effect on all studied traits except for proline, oil percentage, oleic acid, linolenic acid, seed sulfur, and potassium content in the first year, and leaf area, protein percentage, 1000 seed weight, seed number in silique, silique number in plants, oleic acid, and linolenic acid in the second year. Canola response to fertilizer proportions was quite different so that in the first year chemical fertilizations were better, while in the second year the effect of organic fertilizations was more pronounced. High level of organic fertilizer improved nitrate reductase activity, photosynthesis, chlorophyll content, and final seed yield in the second year. It seems that the positive effect of cattle manure would be visible at least 1 year after application. Moreover, canola cultivars differed from each other in terms of some agronomic and physiological traits during each year of the experiment.