NPK fertilization to establish setaria on a lowland soil

Abstract

This work was carried out at the Dairy Cattle Research Center of EMBRAPA, Coronel Pacheco, MG, Brazil, during the periods from January to July 1988, and from December 1988 to June 1989, to compare the effect of various combinations of NPK on the establishment of Setaria (Setaria sphacelata cv Kazungula) in a lowland soil of southeast Brazil. The following fertilizer combinations were compared: 1) = NPK; 2) = NP; 3) PK; 4) P; 5) NK; 6) N; 7) K, and 8) without fertilizer (check). The fertilizer sources and levels used were: P, 50 kg/ha of P₂O₅ as single superphosphate; N, 80 kg/ha, as ammonium sulphate and K, 40 kg/ha of K₂O as potassium chloride. Phosphorus was applied at sowing and N and K fertilizers were divided in three applications starting thirty days after sowing. Phosphorus fertilization had no effect on the number of seeds germinated. Ninety days after sowing the best growth of setaria was attained in the treatments containing phosphorus. In the absence of fertilization the number of plants per square meter decreased with time, being insufficient for the establishment of the grass. The application of N and a K addition to P improved the dry matter yield of both setaria and weeds. Despite a high degree of competition from the weeds, setaria succeeded to establish in the presence of fertilizers P plus N and/or K.