Morfogênese, acúmulo de forragem e teores de nutrientes de Panicum maximum cv. Tanzânia submetido a diferentes severidades de desfolhação e fertilidades contrastantes / Morphogenesis, forage net accumulation and nutritional status of Panicum maximum cv Tanzânia under contrasting fertilization rates and grazing intensities
AUTOR(ES)
Alonso José de Resende Junior
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
05/12/2011
RESUMO
Nitrogen is the most important nutrient regulating pasture production. Response to N fertilization depends on residual leaf area index and other nutrient availability. The aim of this study was to evaluate morphogenetic and structural characteristics, grazing interval, forage yield and nutritional status of Tanzania guinea grass under contrasting defoliation severities and fertilization rates. The six treatments evaluated were factorial combinations between three post grazing heights (20, 30 e 50 cm) and two fertilization rates (unfertilized and fertilized with 500, 300 and 150 kg/ha of nitrogen, K2O e P2O5 respectively), arranged in five completed blocks, totaling 30 paddocks (experimental units) of 400 m² each.25 beef cattle animals were introduced into paddocks to graze every time sward reached 95% of light interception.Measured responses were leaf appearance rate, phyllochron, leaf elongation rate, stem elongation rate, leaf senescence rate, leaf life span, leaf mature length, live leafs per tiller, elongating leafs per tiller, mature leafs per tiller,senescent leafs per tiller and stem length.Nutritional status was measured in the two younger mature leavesof each tiller, considering 100 leaves sampled from 50 tillers of each paddockbetween May and April 2010. Fertilized and unfertilized treatments presented contrasting nutritional status. A high fertilization level combined with the lowest post grazing height resulted in the higher forage yields and leaf elongation rates. The results point to the possibility of enhancing grazing efficiency and animal production when high fertilizations are combined with high grazing intensity
ASSUNTO(S)
capim-tanzânia defoliation desfolha morfogênese vegetal morphogenesis nitrogen nitrogênio pasture - management tanzania guinea grass pastagens - manejoi
Documentos Relacionados
- Morphogenic and structural characteristics and forage accumulation of Panicum maximum cv. Tanzania under different intensities and frequencies of grazing
- Análise de correlação parcial no estudo da morfogênese e do acúmulo de forragem de Panicum maximum cv. ‘Tanzânia’
- Características Morfogênicas e Acúmulo de Forragem do Capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia) em Dois Resíduos Forrageiros Pós-Pastejo
- Morfogênese e dinâmica do perfilhamento de Panicum maximum JACQ. cv. Tanzânia-I sob pastejo
- Respostas de Panicum maximum cv. Tanzânia à associações entre adubação e severidade de desfolha