Fontes de nitrogênio e nível de umidade no solo após a adubação afetam a produtividade do capim mombaça (megathyrsus maximum)?

Abstract

The objective of this study was to evaluate the effect of nitrogen fertilization with different sources and soil moisture level on the production of Megathyrsus maximum cv. Mombasa. The experiment was carried out at the Federal University of Tocantins in a period of 70 days during the months of August to November 2019 in a Typical Neosol Quartzearic Ortic. The treatments were arranged in a completely randomized design in a 2x3 factorial arrangement (nitrogen sources and irrigation time after application) corresponding to 6 treatments and with four replications, totaling 24 plots. Nitrogen was applied at a dose of 30 kg per hectare, in a single dose. The nitrogen sources were Ammonium Nitrate and Urea. The irrigation times after fertilization were: T0- irrigation on the day of application; T4: irrigation four days after application; T8: irrigation eight days after application. After the first irrigation, the plots were irrigated daily with a 6 mm water depth. There was no interaction (P> 0.05) of the frequency of irrigation and nitrogen sources, for the variables dry mass of stem, dry mass of whole plant, dry mass of dead material, dry mass of leaf and leaf: stem ratio. The plant height was influenced (P <0.05) by the nitrogen source, with the treatments receiving fertilization with calcium nitrate presented height 12.4% that the treatments receiving the fertilization with urea. The height of Mombasa grass is influenced by the nitrogen source. The production variables are not influenced by nitrogen sources and irrigation times.