Acta Scientiarum: Animal Sciences (Oct 2011)

Características estruturais de pastos de Brachiaria decumbens diferidos por 140 dias e estratégias de adubação nitrogenada=Structural characteristics of Brachiaria decumbens pastures deferred for 140 days and nitrogen fertilization strategies.

  • Elisângela Oliveira Cardoso,
  • Giselle Caroline Fernandes Martins,
  • Fabiano Ferreira da Silva,
  • Aureliano José Vieira Pires,
  • Paulo Bonomo,
  • Fábio Andrade Teixeira

Journal volume & issue
Vol. 33, no. 4
pp. 333 – 339

Abstract

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O objetivo deste trabalho foi avaliar as características estruturais de pastos de Brachiaria decumbens diferidos por 140 dias, visando determinar a estratégia mais adequada de adubação nitrogenada. Foram estudadas quatro estratégias de adubação no início e no final do verão (0-0, 100-0, 50-50, 0-100 kg ha-1 de N), respectivamente, com quatro repetições. Para avaliação das densidades volumétricas, a forragem foi colhida em três estratos: estrato A- acima de 40 cm; B- 20-40 cm; e C- 0-20 cm do solo. O índice de tombamento foi menor (p The objective of this study was to evaluate the structural characteristics of Brachiaria decumbens pastures deferred for 140 days, in order to determine the most appropriate nitrogenous fertilization. Four fertilization strategies were studied at the beginning and end of summer (0-0, 100-0, 50-50, 0-100 kg ha-1 N), respectively, with four replications. For volumetric density evaluation, forage was harvested in three strata: stratum A- over 40 cm above the soil; B- 20-40 cm; and C- 0-20 cm above the soil. The falling index was lower (p < 0.05) for the fertilization strategy using 100 kg ha-1 N applied at the end of summer. In stratum B (between 20 and 40 cm above the soil), greater (p < 0.05) densities were observed for total forage, leaf blade and green stem using the fertilization strategy of 100 kg ha-1 N applied in early summer (100-0). Greater stem lengths (p < 0.05) were observed in pastures with fertilization strategy 0-100, followed by the 50-50 strategy. The strategies of applying 100 kg ha-1 at the end of summer, followed by the strategy of 50 kg ha-1 nitrogen partitioned in the beginning and end of summer, have a positive influence on the structural characteristics in pastures deferred for 140 days.

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