One experiment was conducted, with the purpose to evaluate the production, quality and the production cost of forage of ryegrass, in continuous grazing, fertilized with two types of fertilizer: Organic-mineral (FOM) and chemical (FC) applied as top dressing. The pasture was implanted in 04/24/1999, with top-seeding, and the level of fertilizer was300kg ha-1 of FOM formula 06-08-08 or FC formula 10-18-20. No significant interaction between fertilizer and evaluation period was observed for the variables studied. The fertilizer sources did not affect the percentage of dry matter (DM) in the residue (22.6 vs 22.2%), the accumulation rate of dry matter (72.3 vs 63.2kg ha-1 of DM), the total forage production (7518 vs 6801 kg ha-1 of DM), the percentage of crude protein (12.8 vs 12.7%), the neutral detergent fiber (57.4 vs 57.4%) and acid detergent fiber (31.0 vs 32.3%), for FOM and FC, respectively. The total cost of the pasture was of 225.90 and 253.50 R$ ha-1, where the fertilizer represented 37.6 and 44.4%, respectively, for FOM and FC. The production cost of the pasture DM was 0.030 and 0.037 R$ kg-1, for FOM and FC, respectively.
organic-mineral fertilizer; cost; yield potential
