Efeito de fontes e doses de nitrogênio na produção e qualidade da forragem de capim-coastcross

Abstract

RESUMO -A produção e a qualidade da forragem do capim-coastcross cultivado em Latossolo Vermelho Distroférrico foram avaliadas no período de novembro a abril dos anos de 1998-1999 e 1999-2000 Effects of sources and rates of nitrogen on forage production and quality of coastcrossgrassABSTRACT -Forage production and quality of coastcross grown on a dark red latosol (Hapludox) were evaluated in 1998-1999 and 1999-2000, from November to April, in São Carlos, São Paulo state, Brazil, under a tropical altitude climate. The experimental design was a randomized block design, in a split-plot arrangement, with four replications. In the main plots were allocated ten treatments, organized in a 2 × 5-factorial scheme (two nitrogen sources: urea and ammonium nitrate, and five N levels: 0, 25, 50, 100, and 200 kg N/ha/cutting, in five consecutive cuttings -repeated measures). Data were analyzed by MIXED procedure of SAS, using a repeated measure model. Nitrogen fertilization increased DM yield, CP concentration, in vitro DM digestibility, and nitrate concentration, and reduced DM and NDF concentrations in the forage. In the first year, N doses associated with 80% of the maximum forage yield were 88 and 78 kg/ha, corresponding to average dry matter yields of 2,769 and 3,202 kg N/ha/cutting, respectively, for urea and ammonium nitrate. In the second year, N doses which produced 80% of the maximum forage yield were 91and 116 kg/ha, respectively, for urea and ammonium nitrate, corresponding to average DM yields of 2,312 and 3,073 kg ha/cutting, respectively.

Effect of <i>Pseudomonas fluorescens</i> and <i>Burkholderia pyrrocinia</i> on the Growth Improvement and Physiological Responses in <i>Brachiaria brizantha</i>

“…In forage grass, nitrate fertilization increases the protein contents and biomass production, but in excess can be toxic to cattle (0.35 to 0.45 dag/kg) [34] [35]. In our study, levels of nitrate in the leaves of co-inoculated plants did not reach toxic levels.…”

Produção animal em pastagem de capim-braquiária adubada com nitrogênio

“…Essas respostas são modestas e evidenciam que a aplicação de N na pastagem tem efeito limitado em melhorar a qualidade da forragem consumida pelos animais. O aumento no teor de PB da forragem com a adubação nitrogenada também tem sido verificado em outros trabalhos de pesquisa (Correa et al, 2007;Mistura et al, 2007;Vitor et al, 2009). Tabela 4.…”

<b>Forage yield of Coastcross-1 pastures inoculated with <i>Azospirillum brasilense

“…Due to their response to fertilization, these grasses are usually grown using high amounts of chemical fertilizers, especially nitrogen fertilizers (Corrêa et al, 2007).…”