Influência da cobertura do solo e doses de nitrogênio na cultura do milho safrinha

Abstract

RESUMOA utilização da cobertura do solo e a adubação nitrogenada em cobertura no sistema de plantio direto, além de essenciais para a conservação do solo podem também auxiliar na disponibilidade de nutrientes para as plantas sucessoras. O objetivo deste trabalho foi avaliar a influência de três diferentes plantas de cobertura de solo e quatro níveis de adubação nitrogenada na cultura do milho safrinha em sistema de plantio direto. O experimento foi conduzido no Núcleo Experimental de Ciências Agrárias da Universidade Federal da Grande Dourados, Dourados-MS. O delineamento experimental foi o de blocos ao acaso no esquema fatorial 3x4, sendo três coberturas do solo (mucuna preta, uma área em pousio com capim camalote e outra com crotalária) e quatro doses de nitrogênio (0, 40, 80 e 120 kg ha -1 ), com quatro repetições. Foram avaliados a altura da planta e a inserção da espiga, diâmetro do colmo, o diâmetro e o comprimento de espigas, o peso de cem grãos e a produtividade. A cobertura do solo influenciou no diâmetro basal do colmo e na produtividade de grãos de milho. O incremento das doses de nitrogênio favoreceu a grande maioria dos componentes de produção da cultura do milho. A utilização das coberturas como mucuna preta e capim camelote e as doses de nitrogênio, aumentaram a produtividade de grãos de milho. Palavras-chave: conservação do solo, produtividade, Zea mays L. Influence of cover crops and nitrogen rates in winter corn crop ABSTRACTThe use of cover crops along with the nitrogen application in no-tillage system, besides being essential for the conservation of soil, can also assist in nutrient availability to succeeding crops. The aim of this study was to evaluate the influence of three different ground cover plants and four levels of nitrogen fertilization on winter maize under no-tillage system. The experiment was conducted at the Experimental Center of Agricultural Sciences of the Universidade Federal da Grande Dourados, Dourados-MS. The experiment was conducted in randomized blocks in a 3x4 factorial design, with three ground covers (velvet bean, an area under fallow with 'camalote' grass and another with sunn hemp) and four levels of nitrogen (0. 40. 80 and 120 kg ha -1 ), with four replications. The plant height and ear height, stem diameter, the diameter and length of ears, weight of hundred grains and productivity of winter corn were evaluated. Soil cover influenced the basal stem diameter and grain yield of maize. The increment of nitrogen favored the vast majority of yield components of corn. The use of hedges such as velvet bean and grass camelote and nitrogen increased the grain yield of maize.

Corn Agronomic Attributes in Succession of Leguminous Cover Crops and Nitrogen Doses

“…The probable synergism among the atmospheric N fixation by leguminous and nitrogen fertilization is more evident in the 2013/2014 harvest, when a significant increase of up to 35% in dry biomass and up to 60% in N accumulation was observed in the treatments that received the dose of 180 kg ha -1 (Table 1). These results meets with Weber et al (2009) and Torres et al (2014).…”

Biomass components of Pennisetum purpureum cv. Roxo managed at different growth ages and seasons

“…The highest daily increases in GSB in the rainy season were possible due to rainfall and the maintenance fertilisation carried out at the beginning of the experiment. Nitrogen fertilisation under satisfactory water conditions provides an increase in the stem elongation rate (COUTINHO et al, 2015) and larger stem diameters (TORRES et al, 2014). Although late cuttings provide a greater amount of harvestable biomass, the increase in rest period increased the participation of GSB in GFB.…”

Chemical attributes of the soil and agronomic characteristics of maize as a monocrop and intercropped with herbaceous and woody legumes in the savannah of Roraima, Brazil

“…These results agree with those of Santos et al (2010), who recorded greater lengths for maize cobs when grown intercropped with jack bean. However, Torres et al (2014) working with cover crops and nitrogen fertiliser in a crop of off-season maize, recorded no statistical difference for the length or diameter of the cobs. Growing maize under an alley cropping system, the total productivity of husked cobs showed no difference between the intercrops, while for commercial cob productivity, the treatments that provided the greatest weight were the intercrop with crotalaria (5,600.04 kg ha -1 ) and with jack bean (5,299.42 kg ha -1 ), there being no statistical difference between the two as shown in Table 6.…”