Adubação nitrogenada no diferimento e seus impactos sobre a produtividade de matéria seca e seus componentes morfológicos do capim mombaça

Abstract

The objective of this work was to evaluate deferment times combined with nitrogen fertilization on the production and structural components of Mombasa grassgrass pastures. The study was conducted at the Federal Rural University of the Amazon, Parauapebas, Pará, Brazil, from April 4 to July 30, 2018. The design was in randomized blocks, in a 3x2 factorial arrangement, with three deferral periods (80, 60 and 40 days) and nitrogen fertilization levels (0 and 50 kg N ha-1) with six replications. The cuttings simulating the last grazing occurred on April 26, May 15 and June 3, 2018. Height, forage dry matter production and its morphological components (stem, leaf dead material) were evaluated. There was interaction between deferment period and nitrogen fertilization (P <0.05) for the production of total dry matter, leaves, stalk and dead material. When nitrogen fertilization was carried out, higher dry matter yield (P <0.05) was verified for the productive characteristics at 80 days of deferment. For the other periods, there was no difference (P> 0.05) (P <0.05), leaf production for the fertilized and deferred treatment for 80 days, and higher values for nitrogen fertilization and deferment in the 80-day period for the percentage of stalk and lower percentages of dead material registered at 40 days after deferment with the use of nitrogen fertilization. The nitrogen fertilization provides greater dry matter production in deferred Mombasa Grass for 80 days, proportionally accompanied by the morphological components of leaf, stem and dead material.