Nitrogen fertilization and intercropping of Trachypogon plumosus with Stylosanthes capitata cv. Lavradeiro under seeding densities

Abstract

The effect of nitrogen levels (0, 40, 80, 120, 160, and 200 kg of N ha-1) on pure pastures of Trachypogon plumosus and the sowing densities of Stylosanthes capitata cv. Lavradeiro (1.0; 2.0; 3.0 and 4.0 kg of seeds ha-1) on forage yield, botanical composition and apparent fixation and transfer of nitrogen (N) was evaluated under field conditions. Nitrogen fertilization quadratically affected grass forage yields and its nitrogen content, and the maximum values were estimated by the application of 154.6 and 155.7 kg N ha-1, respectively. The legume forage yield was directly proportional to the densities of its sowing, occurring the opposite for the grass forage yield. The forage yields of the grass-legume mixture, independently of legume sowing density, were higher than those showed by the grass grown alone and for all doses of N evaluated. The use of legume sowing densities between 2.0 and 3.0 kg ha-1 allows the establishment, the productive stability and the persistence of the grass-legume mixture. The apparent N fixation by the legume and its transfer to the grass were directly proportional to the legume sowing densities.