Corn agronomic traits and recovery of nitrogen from fertilizer during crop season and off-season.

• Autor(a) principal: GARCIA FUENTES, L. F.
• Data de Publicação: 2018
• Outros Autores: SOUZA, L. C. F. de, SERRA, A. P., RECH, J., VITORINO, A. C. T.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1100588
• topic: Manejo da adubação nitrogenada; Nutrição de plantas; De N pelo solo; N-fertilizer management; Soil-N supply; Zea Mays; Fertilidade do Solo; Plant nutrition; Soil fertility

The objective of this work was to evaluate corn agronomic traits in a cultivation subjected to different N rates, during the fall?winter (off-season) and spring?summer crop seasons, and N recovery from fertilizer. The experiment was set up in a randomized complete block design with four replicates, in a 5x2 factorial arrangement, with the following treatments: five N topdressing rates ? 0, 30, 60, 90, and 120 kg ha-1 ?, using urea as source; and two crop seasons, fall?winter and spring?summer. The following variables were determined: plant height, height of the first ear insertion, number of grains per ear, diameter and length of ear, 1,000-grain weight, N concentration in the leaves and grains, grain-protein concentration, grain yield, N recovery from fertilizer, and soil-N supply. Nitrogen rates in the fertilizer in the fall?winter season had no effect on grain yield, although corn agronomic traits showed a greater reliance on fertilizer-N rates in that season than in the spring?summer, which is a season associated to a greater capacity of soil-N supply to plants. The quantification of soil-N supply enabled knowing the nutrient dynamics during the fall?winter and the spring?summer seasons, which may be useful to guide N fertilization of corn.