Optimal application rates of inorganic nitrogen (N) and phosphorus (P) as well as cattle manure were estimated using Response Surface Methodology (RSM). A central composite design (CCD) was conducted at field level during the 2012-13 and 2013-14 growing seasons. The applied levels of N were 0, 150 and 300 kg ha-1 N in form of urea. The used levels for P fertilizer were 0, 100 and 200 kg ha-1 (P2O5) and for cattle manure were 0, 15 and 30 t ha-1, respectively. Seed yield (SY), biological yield (BY were measured. N losses (NL) and agronomical N use efficiency (ANUE) were estimated. Increased N and P rates up to 200 kg ha-1 made in increased SY. Rate optimization of N, P and manure got based on economic, environmental and eco-environmental scenarios. In economic scenario, using 145.4 kg ha-1 N, 200 kg ha-1 P and 18.4 t ha-1 manure resulted in 6500 kg ha-1 SY with ANUE of 10.49. In environmental scenario, by application of 21.21 kg ha-1 N, no application of P and applying 16.3 t ha-1 manure, SY and ANUE of 3160 kg ha-1 and 9.08 were obtained, respectively. In eco-environmental scenario, 144.7 and 34.3 kg ha-1 N and P plus 30 t ha-1 manure resulted in 4031 kg ha-1 SY and a considerable high ANUE of 16.50 succeeding 36.4% higher than economic scenario. The results of this study showed that the eco-environmental scenario had more advantages than the other scenarios mainly due to higher ANUE.

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