Estrutura do pasto de capim-marandu diferido com alturas e doses de nitrogênio variáveis

• Ano de defesa: 2013
• Autor(a) principal: Cordeiro, Marcos Guilherme
• Orientador(a): Fonseca, Dilermando Miranda da
• Banca de defesa: Sousa, Braulio Maia de Lana
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado Profissionalizante em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Brachiaria brizantha; Diferimento; Manejo; Pastagem; Adubação
• Palavras-chave em Inglês: Brachiaria Brizantha; Deferral; Management; Grazing; Fertilization
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA
• Link de acesso: http://locus.ufv.br/handle/123456789/5979

The objective of this work was to generate some recommendations of height and doses of nitrogen at the beginning of differencing which result in differed pasture with an adequate mass and forage morphological composition. The experiment was carried out from March to June, 2012, in a pasture area with Brachiaria brizantha cv. Marandu, established in 2000 on Capim-Branco farm, which belongs to the Federal University of Uberlandia, in Uberlandia, state of Minas Gerais. Two pasture heights (15 and 30 cm) and four doses of nitrogen (0, 40, 80 and 120 kg/ha) were evaluated at the beginning of the differencing period. They were arranged in a 2 x 4 factorial design. It was used a complete random design with three replicates. The plots with 6 m2 (2 x 3 m) were allocated in the pasture area after animals were removed from the pasture on 3/15th/2012. On this date, the marandu grass was at a height of 30 cm. The 30- and 50-cm heights were mechanically established by using pruning shear. The doses of nitrogen fertilization were manually applied on the pasture after adjustment of the heights. Agriculture urea was used as source of nitrogen at a single dose. Variation in the pasture height during differing period was not influenced by the two evaluated initial heights (15 or 30 cm). However, the dose of nitrogen had a linear and positive effect on this trait. Number of basal tiller was higher in the 15-cm differed pasture than in the 30-cm pasture only when it was applied 120 kg/ha of N. Values of leaf area index (LAI) did not vary with the initiation height of pasture. Heights of the pasture and the extended plant increased according to the nitrogen fertilization. Tillers did not fall in the differed pastures. The increment in the dose of nitrogen in the beginning of diferring period had a positive and quadratic effect on the forage mass only when the pasture was 15-cm differed. Regarding the conditions with no application of nitrogen and of those which had an application of 80kg/ha of this nutrients, 30-cm differed pastures presented greater forage mass than the 15-cm differed pasture. Brachiaria brizantha cv. Marandu differed pastures at 15 or 30 cm in the beginning of differing and fertilized with 80 kg/ha of N presented an adequate structure and potential for a good animal performance in the dry season.