Desempenho da cultura do milho em resposta ao uso de fontes de nitrogênio

Abstract

The corn crop, due to its characteristics, is highly responsive to nitrogen fertilization, especially when grown after another species of the same botanical family. However, as it is a highly dynamic nutrient in the soil-plant-atmosphere system, nitrogen is susceptible to various forms of loss, the main ones being ammonia volatilization (NH3) and nitrate leaching (NO3-). This work aims to evaluate the effect of using different nitrogen sources on morphological characters (plant height, ear insertion height and stem diameter), yield components (number of grains per ear, number of rows per ear and mass of a thousand grains) and the grain yield of the maize crop. The experimental design was a randomized block, with five treatments: Urea, Ammonium Sulfate, Yarabela and Protected Urea (stabilized), in addition to a control treatment and four replications, totaling 20 experimental units. The application of the sources was done in coverage, in parts, in the stages V4/V5 and V6/V7 of development of the corn crop, at the dose of 200 kg ha-1 of N. The evaluations of the morphological characters, yield components and Grain yields were made at the physiological maturation stage. The use of different N sources did not influence the productivity or the yield components of the crop, possibly due to the long water deficit observed during the experimental period.