RESPONSE OF THE TYPE OF NITROGEN RESOURCE IN THE QUALITY OF MAIZE CULTIVATED IN SOUTHERN AMAZONIA

Abstract

Nitrogen is the nutrient most absorbed by maize crop and is usually the most limiting for development, especially when it is intended to work with maize cultivars with grain suitability and silage. The experiment was conducted in an experimental area of the Mato Grosso State University, Brazil. The objective of this work was to evaluate the vegetative and productive characteristics of a maize cultivar of dual aptitude as a function of sources and nitrogen doses in the municipality of Alta Floresta-MT, located in the region of the Southern Amazon. The experimental design was a randomized complete block design in a 5x2 factorial scheme. The treatments consisted of the combination of two nitrogen sources (urea and ammonium sulfate) and five nitrogen doses (0, 65, 130, 195 and 260 kg ha-1), with four replicates. For the vegetative characteristics, no nitrogen source effect occurred. Only for plant height and spike insertion occurred a difference between the nitrogen rates used, where they were adjusted to a quadratic regression model with maximum response, respectively, at the doses of 112.5 and 75.0 kg ha-1 of N. There was an effect of doses and nitrogen sources on the productive characteristics evaluated.