Efici?ncia de recupera??o de nitrog?nio pela cana de-a??car em fun??o da aduba??o nitrogenada de plantio e da inocula??o com bact?rias promotoras do crescimento vegetal

• Ano de defesa: 2017
• Autor(a) principal: Pereira, Willian
• Orientador(a): Souza, Sonia Regina de
• Banca de defesa: Souza, Sonia Regina de, Lima, Eduardo, Schultz, Nivaldo, Cunha, Raquel Capistrano Moreira Valtas, Olivares, F?bio Lopes
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Agronomia - Ci?ncia do Solo
• Departamento: Instituto de Agronomia
• País: Brasil
• Palavras-chave em Português: Bact?rias endof?ticas. .; Saccharum sp; T?cnicas isot?picas
• Palavras-chave em Inglês: Endophytic Bacteria; Saccharum sp; Isotopic Techniques
• Área do conhecimento CNPq: Agronomia
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/4439

Nitrogen fertilizer is one of the main responsible for fossil energy consumption and greenhouse gases emissions on sugarcane production cycle. The increase of efficiency on use of N is a matter of interest in reducing production costs and increasing energy balance of sugarcane production. The search for technologies that increase the efficiency of nitrogen fertilization and for productive and efficient varieties of sugar cane in the use of N is relevant and strategic for sugarcane production in Brazil. This work objective was to evaluate the recovery efficiency of N fertilizer by sugarcane inoculated with plant growth promoting bacteria (BPCV) and N recovery efficiency by three commercial varieties of sugarcane. Two experiments were installed in the experimental field of Embrapa Agrobiologia, Serop?dica, RJ. The first experiment was installed in a dystrophic Yellow Red Ultisol and conducted for three years. A second experiment was installed in a dystrophic Yellow Ultisol, where the cane plant and first ratoon were harvested. On first experiment microparcels with 15N application were installed in treatments that received nitrogen fertilization, both in cane plant and evaluated soeches. On second trial three sugarcane varieties were used: RB867515, IACSP95-5000 and CTC 15 and two nitrogen rates (50 and 100 kg N ha-1) plus one control without fertilization were applied. In cane plant, microparcels were installed with 15N-urea at a dose of 50 kg of N ha-1 and on first ratoon the microparcels were installed with application of 15N-ammonium sulphate in all treatments. On the first experiment the inoculation with BPCV increased the content of N in the aerial part in some evaluations throughout the cycle of plant cane, but this result did not extend until the harvest. N fertilizer participation in plant nutrition was 13% on the average of the three cycles studied, other sources accounted for a large part of N in the aerial part. The 15N-fertilizer recovery efficiency was 50, 30 and 20% in cane plant, first and second ratoon, respectively, but without differences between treatments. On second experiment nitrogen fertilization promoted growth increase, shoot yield and N extraction on three varieties studied. The varieties altered the chemical characteristics of soil in function of nitrogen fertilization of planting. The RB867515 variety was the most productive and with the largest extractions of N in cane plant. Nitrogen fertilization of planting reflected in increased productivity on sequent soybean only in RB867515 variety. The average recovery of N-fertilizer by the varieties in plant cane cycle was 41%. Individually, the recovery was 38, 39 and 47%, on varieties RB867515, CTC 15 and IACSP95-000, respectively. At the first stand the nitrogen fertilization of planting influenced the recovery efficiency of N in CTC 15 variety, being the most efficient over the others. The management of nitrogen fertilization of planting in function of the variety can influence the productivity gain of subsequent ryegrass of RB867515