Yield of six grasses cultivated by grazing under effect of different nitrogen fertilization and annual seasons

Abstract

Dry matter yield of six irrigated grasses cultivated by grazing under different nitrogen fertilization and annual seasons in Brazil. The experiment was conducted in a split plot design, tends a factorial design 4 x 6 (nitrogen and grasses) in the plots and season (autumn/winter and spring/summer) in the split-plots, in a completely randomized block, with four repetitions. The nitrogen doses were of 100; 300; 500 and 700kg/ha/ano and the grasses were: Xaraes, Mombaça, Tanzania, Pioneiro, Marandu and Estrela. The irrigation system was semi-fixed conventional sprinkling. The dry matter yield was obtained by means of the dry material in ventilated stoves at 60°C, for 72h. The appraised grasses presented different dry matter yield. The factor temperature was the responsible for the differences among seasons. The increase of the nitrogen fertilizer did not affect the dry matter yield due to methodology for its determination and for the degradation of the physical quality of the soil. It was observed, in the general, that the Xaraes, Tanzania and Mombaça presented larger, and Pioneiro, smaller dry matter yield, respectively. The highest temperatures happened in the spring/summer season and provided larger dry matter yield. The nitrogen fertilization did not influence the dry matter yield of the appraised grasses.