AGRONOMIC CHARACTERISTICS AND ECONOMIC EVALUATION OF MAIZE UNDER NITROGEN DOSES IN THE FORM OF COMMON AND PELLET UREA

Abstract

Corn is the third commodity producer in Brazil, second only to soybeans and beef. Despite the technological advances that have been occurring in the agricultural environment in recent years, the productivity of the crop has remained almost constant over the years, close to 2,500 kg ha^-1, a value considered low when compared to other countries. Nitrogen fertilization is a complex factor for several crops due to the various transformations that occur with N in the soil and influence its use by plants. The objective of this work was to study the effect of common and pelleted urea in different doses on the agronomic characteristics of maize in Barreiras city, state of Bahia, as well as its economic evaluation for the 2013/14 harvest. The treatments consisted of a 2 x 3 factorial scheme, two types of urea (conventional urea and polymerized urea) with three doses of nitrogen (N) (75, 100, 125 kg ha^-1). The following variables were analyzed: plant height, ear diameter, dry weight of a thousand grains, yield estimate and economic evaluation. Only for the variable weight of a thousand grains, a significant difference was observed between nitrogen sources. The application of nitrogen doses directly influenced maize production, regardless of the source used, with an increase of 6.50 kg ha-1 of maize for each kg of N applied. The 75 kg ha^-1 dose of common urea presented the best economic return for the conditions tested.