Growth dynamics and morphogenesis of Trachypogon plumosus under soil fertility correction levels and regrowth ages

Autores

  • Newton de Lucena Costa Embrapa Roraima
  • Anibal de Moraes UFPR
  • Paulo César Faccio de Carvalho UFRGS
  • Alda Lúcia Gomes Monteiro UFPR
  • Antônio Carlos Vargas Motta UFPR
  • Ricardo Augusto de Oliveira UFPR

DOI:

https://doi.org/10.18227/1982-8470ragro.v7i1.825

Palavras-chave:

Dry matter. Growth rate. Leaves. Tillering.

Resumo

The effects of soil fertility correction levels (control, liming, fertilization and liming + fertilization) and regrowth ages (21, 28, 35, 42, 49, 56, 63, 70, 77 and 84 days) on growth dynamics, forage yield and morphogenetic and structural characteristics of Trachypogon plumosus were assessed in Roraima´s savannas. Dry matter yields (DMY), absolute growth rate (AGR), tiller population density (TPD), number of live leaves (NLL), final leaf length (FLL), leaf area index (LAI), leaf elongation rate (LER) and leaf senescence rate (LSR) increased consistently with regrowth age, while average growth rate (AvGR), and leaf appearance rate (LAR) were inversely proportional to regrowth age. The grass showed high responsiveness to the soil fertility improvement. Liming + fertilization or fertilization alone promoted higher DMY (2,116 and 1,759 kg ha-1), AGR (40.5 and 33.6 kg ha-1.day), AvGR (32.5 and 27.9 kg ha-1.day), NLL (5.5 and 4.9 leaf tiller-1), LAR (0.119 and 0.109 leaf day-1 tiller-1), LER (2.53 and 2.06 cm day-1 tiller-1), FLL (22.1 and 18.9 cm), LAI (2.64 and 2.83) and TPD (762 and 725 tillers m-2). To maximize the forage use efficiency and to prevent losses to leaves senescence, it is recommended a regrowth period between 56 to 63 days for fertilization and liming + fertilization, and 63 to 70 days for control or liming pastures.

Biografia do Autor

Newton de Lucena Costa, Embrapa Roraima

Pesquisador da Embrapa Roraima

Anibal de Moraes, UFPR

Professor-Doutor da UFPR

Paulo César Faccio de Carvalho, UFRGS

Professor do Departamento de Plantas Forrageiras e Agrometeorologia da UFRGS

Alda Lúcia Gomes Monteiro, UFPR

Professor do Departamento de Zootecnia da UFPR

Antônio Carlos Vargas Motta, UFPR

Professor do Departamento de Solos da UFPR

Ricardo Augusto de Oliveira, UFPR

Professor do Departamento de Fitotecnia da UFPR

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Publicado

02/05/2013

Edição

Seção

Original Scientific Article