Effect of nitrogen and potash fertilizations on ruzigrass dry matter yield and composition

The present work was held at the Experimental Station of the Husbandry Institute located in Ribeirao Preto, Sao Paulo, Brazil. The aim of the work was to study the effect of nitrogen and potash fertilization on dry matter yield and composition of Brachiaria ruziziensis Germain & Everard. The experimental design used was randomized blocks and the treatments were arranged in a 2 x 2 factorial (two nutrients in two levels: 0 and 1). Level 1 of the nutrients was calculated to replace 3% and 2% for N and K, respectively, of the total removed forage at each harvest (considering dry matter at 65 degrees). Nitrogen fertilization increased the dry matter and crude protein yields in 319 and 598%, respectively. The effect of potash was not statistically significant. Nitrogen fertilization also increased crude protein, sulphur, zinc and copper forage concentrations. There was decrease in the forage phosphorus and calcium concentrations when the grass was fertilized with nitrogen and potash.