Publicação: Growth, herbage accumulation, and nutritive value of ‘tifton 85' bermudagrass as affected by nitrogen fertilization strategies
Carregando...
Data
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Tipo
Artigo
Direito de acesso
Acesso aberto
Resumo
Nitrogen fertilization affects ‘Tifton 85' bermudagrass (Cynodon spp.) herbage accumulation (HA) and nutritive value; however, forage response may be affected by N fertilizer source, application levels, and environmental conditions. This 2-yr study evaluated the effect of different N fertilization strategies on Tifton 85 bermudagrass responses in a tropical soil from southeast Brazil. Treatments were two N sources (ammonium nitrate [AN] and urea) applied at 0, 60, 120, 180, and 240 kg N ha-1 harvest-1. Fertilizer sources were enriched with 15N to quantify the recovery of fertilizer-derived N. Forage was harvested at 30-d intervals to evaluate HA and shoot N concentration. Leaf area index (LAI), intercepted photosynthetically active radiation (PARi), and chlorophyll index were measured 1 d before harvest. Ammonium nitrate and urea resulted in similar Tifton 85 HA. Maximum Tifton 85 HA (4.6 Mg ha-1 ) was reached at the fertilization level of 210 kg N ha-1 harvest-1 while critical shoot N concentration, herein defined at 90% relative production, was 23.7 g kg-1. Similarly, critical PARi and LAI were 71% and 4.7 m2 m-2, respectively. Nitrogen recovery in the plant and soil was greater for urea (52%) than AN (41%). Despite the relatively greater shoot N accumulation, N recovery decreased as N levels increased. Nitrogen application level should be adjusted to optimize HA, nutritive value, and N recovery.
Descrição
Palavras-chave
Idioma
Inglês
Como citar
Crop Science, v. 57, n. 6, p. 3333-3342, 2017.
