Semeadura de capim braquiária em pós-emergência da cultura do milho para obtenção de cobertura morta em sistema de plantio direto
Carregando...
Data
2003-06-23
Autores
Bernardes, Lister Fernandes [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Em sistema de plantio direto, a produção de fitomassa das culturas implantadas com este fim, logo após a colheita da cultura de verão, não tem sido satisfatória. Assim sendo, buscou-se avaliar os efeitos de épocas e densidades de semeadura de Brachiaria decumbens em pós-emergência da cultura do milho em seus teores foliares de nutrientes, produtividade de grãos e componentes de produção, quantidades totais de fitomassa (restos culturais do milho + braquiária + plantas daninhas) de raízes e de superfície e seus respectivos teores e quantidades de nutrientes absorvidos. O experimento foi conduzido a campo, em Ituverava, SP, empregando-se blocos casualizados em esquema fatorial 2x2 com uma testemunha e quatro repetições. Os tratamentos foram milho solteiro (testemunha), fator época de semeadura de capim braquiária na entrelinha da cultura de milho, quando o mesmo se encontrava no estádio V5 (cinco folhas completamente desdobradas) e V7 e fator densidade de semeadura de braquiária, de 20 e 40 sementes viáveis/m2. Semeou-se o milho com 80 cm entrelinhas, no dia 06 de novembro. Em cada entrelinha semeou-se duas linhas de braquiária com 40 cm entre si. Colheu-se o milho em 06 de março do ano seguinte e sete meses depois quantificou-se a fitomassa. O capim braquiária não afetou os componentes produtivos e a produtividade de grãos. A fitomassa foi superior com a utilização de capim braquiária, principalmente quando introduzida no estádio V5 e na maior densidade de semeadura. As quantidades de N, P, K, Ca, Mg e Mn/ha contidos na fitomassa correlacionaram-se positivamente com as produtividades da mesma, não sendo significativa para Zn e Cu.
In no-tillage system, the production of phytomass of the crops introduced for this purpose, soon after the summer crop, it hasn't been satisfactory. Therefore, was evaluated the effect of the times and densities of Brachiaria decumbens planting in post-emergence of the corn crop in its foliar concentration of the nutrient, grains yield and production components, total amounts of phytomass (corn crop remains + signalgrass + weed) of roots and of surface and respective concentration and amounts of absorbed nutrients. The experiment was conducted in the field, in Ituverava, São Paulo, where the randomized blocks were used in a 2 x 2 factorial with one control plot and 4 repetitions. The treatments were the single corn (control plot), moment factor of the signalgrass's planting into the between lines of the corn crop, when the same thing was found in the stage V5 (five leaves totally unfolded) and V7, and the density factor, of 20 and 40 seeds viáveis/m2. The corn was sowed with between lines of 80 cm, on November 6th. In each between lines, two lines of signalgrass were sowed with 40 cm between them. The corn was harvested on March 6th of the following year and seven months the fitomassa it was quantified. The signalgrass hasn't caused any effect in the productive components and grains yield. The total phytomass yield was higher with the use of signalgrass, mainly when it was introduced in the stage V5 and in the largest density planting. The amounts of N, P, K, Ca, Mg and Mn/ha in the total dry matter presented positive correlation with the yields of the same, being not significant for Zn and Cu.
In no-tillage system, the production of phytomass of the crops introduced for this purpose, soon after the summer crop, it hasn't been satisfactory. Therefore, was evaluated the effect of the times and densities of Brachiaria decumbens planting in post-emergence of the corn crop in its foliar concentration of the nutrient, grains yield and production components, total amounts of phytomass (corn crop remains + signalgrass + weed) of roots and of surface and respective concentration and amounts of absorbed nutrients. The experiment was conducted in the field, in Ituverava, São Paulo, where the randomized blocks were used in a 2 x 2 factorial with one control plot and 4 repetitions. The treatments were the single corn (control plot), moment factor of the signalgrass's planting into the between lines of the corn crop, when the same thing was found in the stage V5 (five leaves totally unfolded) and V7, and the density factor, of 20 and 40 seeds viáveis/m2. The corn was sowed with between lines of 80 cm, on November 6th. In each between lines, two lines of signalgrass were sowed with 40 cm between them. The corn was harvested on March 6th of the following year and seven months the fitomassa it was quantified. The signalgrass hasn't caused any effect in the productive components and grains yield. The total phytomass yield was higher with the use of signalgrass, mainly when it was introduced in the stage V5 and in the largest density planting. The amounts of N, P, K, Ca, Mg and Mn/ha in the total dry matter presented positive correlation with the yields of the same, being not significant for Zn and Cu.
Descrição
Palavras-chave
Milho, Cobertura morta, Brachiaria decumbens
Como citar
BERNARDES, Lister Fernandes. Semeadura de capim braquiária em pós-emergência da cultura do milho para obtenção de cobertura morta em sistema de plantio direto. 2003. iii, 42 f. Dissertação (mestrado) - Universidade Estadual Paulista, Faculdade de Ciências Agrárias e Veterinárias, 2003.