Manejo da adubação nitrogenada na cultura do milho: métodos de aplicação

Abstract

Corn (Zea mays L.), an important commodity for Brazilian agribusiness, increasingly requires a more rational use of inputs. Nitrogen (N) is the nutrient required in greater quantity by the corn crop and also the most complex to manage and the one that most burdens the production cost. Improvements in the management of nitrogen fertilization of the crop become essential for increasing productivity, and it is necessary to find alternatives to increase the efficiency in the use of the nutrient. Greater use of N can be achieved by synchronizing applications and the period of high demand for the nutrient by the crop, as well as by the application method. The objective of this work was to evaluate the corn response to different nitrogen fertilization distribution methods. The study was conducted in the experimental area of the Federal University of Pampa Campus Alegrete, which is located in the physiographic region of the West Frontier of the State of Rio Grande do Sul. The study consists of three treatments related to the management of nitrogen fertilization, which are: Traditional: nitrogen fertilization applied in the traditional way, distributed in the total area; Incorporated: nitrogen fertilization fully incorporated into the soil; Precision: nitrogen fertilization directed towards the cultivation line. The nitrogen fertilizer used as source was urea. The experiment was conducted in a randomized block design, with 4 replications, under a surface irrigation system, and water conduction through polytubes. Irrigation management based on variable irrigation shift with crop evapotranspiration. The NK 467 VIP3 hybrid was used, at a density of 75 thousand seeds per hectare. With the management carried out for this year, it can be observed that the different methods of application of nitrogen fertilization did not result in expressive differences in terms of productivity.