Efeito do manejo do solo com plantas de cobertura, cultivares/híbridos e nitrogênio na cultura do milho

• Autor(a) principal: AGUIAR, Renata Alves de
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tde/2648
• topic: Zea mays L.; Mucuna aterrima; Crotalaria juncea; relação benefício/custo; nutrição mineral; 1. Milho Cultura 2. Plantas de cobertura 3. Solo Manejo Viabilidade econômica 4. Milho híbrido Fertilizantes hidrogenados 5. Nutrição mineral; Zea mays L.; Mucuna aterrima; Crotalaria juncea; the benefit / cost; mineral nutrition; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::PRODUCAO DE MUDAS

The corn is the main cereal produced in Brazil and its productivity is very affected by the improper use of nitrogen, which is the nutrient absorbed in larger quantities and therefore responsible for a significant share in production costs. Due to the importance of nitrogen for the corn crop becomes necessary studies to reduce the amount of nitrogen applied to the crop, reducing losses and increasing the efficiency of its use, beside minimize environmental risks. One way have been studied to reduce the amount of nitrogen applied and increase the efficiency of use of inorganic nitrogen, from the fertilizer, it is the combination of plants that cover the ground with nitrogened fertilizer. The study aimed to determine the economic viability and the effect of soil management with the use of soil cover plants, hybrids and nitrogen doses in coverage in the vegetative and reproductive characteristics, related to productivity of corn. The corn, in the experiment, was planted at begning of February in the field trial of Embrapa Arroz e Feijão, Red Latosol Distrophic. The experimental design was a randomized complete block with three replicates the arrangement of plots in sub-sub-divided. The plots were formed by four types of soil management: direct planting of corn on the black mucuna stubble (Mucuna aterrima Merr.); direct planting of corn on the of crotalária juncea stubble (Crotalaria juncea L.); direct planting of corn on vegetation spontaneous (aside) and planting corn in the system of conventional tillage (arado of aiveca). The subplots were formed by five doses of nitrogen in coverage: 0, 45, 90, 180 and 360 kg ha-1 of nitrogen in coverage, and the sub-sub-plots of four hybrids of corn: BRS 3003, AG 1051, Green Corn HT-1, HT-2 Green Corn. The analysis of the benefit / cost was performed on the basis of prices of materials and services raised in April 2007. The benefit / cost in the various systems was held in the Excel spreadsheets, and economically viable a relationship exceeding 1.0. It was concluded that: there is effect of hybrid and soil management on vegetative characteristics such as plant height and the first spik and on productive characteristics as income from pulp and grain and mass in a thousand grains of corn, and there is no interaction between hybrid, soil management and dose of nitrogen in coverage of the productivity of corn. The best soil management as the benefit / cost is the fallow without any addition of nitrogen in coverage, followed by the system of conventional tillage with 45 kg ha-1 and without the addition of nitrogen.