کارایی جذب و بهره وری نیتروژن در تناوب های دو گانه گندم در شرایط مقادیر متفاوت نیتروژن در ایلام

This study was carried out under temperate climate condition of Ilam province, Iran, during 2012-2013 growing seasons to determine the suitable crop rotation for enhancing nitrogen uptake, utilization, and use efficiency of wheat. A two factor experiment was laid out as split plot arrangement (RCBD) with four replications. The main plots consisted of 6 pre-sowing plant treatments (control, Perko PVH, Buko, Clover, Oilseed radish and combination of three plants Ramtil, Phasilia, clover), and sub-plots were allocated to four levels of nitrogen fertilizer (Zero, fertilizer recommendation, 50% lower and 50% higher than the recommended fertilizer). Results showed that nitrogen use efficiency (NUE), nitrogen uptake efficiency (NUpE), nitrogen utilization efficiency (NUtE) and Nitrogen efficiency ratio(NER) in wheat were significantly affected by crop rotation and nitrogen fertilizer and their interaction. The lowest and highest nitrogen use efficiency were in oilseed radish: wheat and fallow: wheat rotation, The high frequency of nitrogen use efficiency in oilseed radish: wheat due to high utilization efficiency of nitrogen in the rotation. The highest and lowest Nitrogen utilization efficiency (NUtE) were observed in oilseed radish: wheat and fallow: wheat rotation, Respectively. Because the total performance Perko: wheat rotation as fertilizer recommendation nitrogen and more than the recommended were greater than the other rotation, Thus Perko: Wheat rotation with the consumption nitrogen as fertilizer recommendations for wheat due to economic performance and high nitrogen uptake and use efficiency, Were evaluated better than any other rotation.