Phosphorus is essential for forage crops and fertilization combined with reactive and natural sources of phosphorus can increase the quality and yield of Piata grass. The objective of this study was to evaluate the production and the relationship between the components of Piata grass subjected to different combinations of reactive and rock phosphate. The experiment was conducted in a greenhouse in a randomized block design with seven replications. Treatments consisted of four combinations of sources and reactive phosphate rock (equivalent to 70 kg ha-1 of P2O5): absence of phosphate fertilizer (control); fertilization with Algeria reactive rock phosphate; fertilization with 50% of Algeria reactive rock phosphate and 50% fertilization with single superphosphate and single superphosphate fertilization. The Piata grass was grown for three cuttings for characterization of dry matter production of tillers, leaves, pseudostem, relations between roots and leaf/pseudostem and shoot/root part. Phosphorus fertilization, regardless of the source, provided an increment in the production of dry matter of leaves, pseudostem and shoots of Piata grass in the second and third cuttings of evaluation and on the average, indicating increased forage production.
yield; Urochloa brizantha ; dry matter; fertilizer phosphorus