Efeitos de fontes e doses de nitrogênio em soqueira de cana-de-açúcar, cultivar SP 79-1011

Abstract

Currently sugar cane is one of the main crops in the world scene, mainly because of the search for alternatives to minimize the effects of global warming. In this context the ethanol is a fundamental tool in eminence. The nitrogen is one of the most required nutrients by the crop and the increase in its doses has promoted significant increments in the sugar cane ratoon yields. This work was carried out with the objective of finding out the effect of either urea or ammonium nitrate in five doses on the remaining straws after the sugar cane cut, third ratoon crop, without previous burning, on leaf nitrogen contents, sugarcane ratoon yield or the sugar cane chemical-technological characteristics. The experiment was installed in a Red-Yellow Latosol dystropc area at alembic João Mendes "JM", located in the municipality of Perdões, Minas Gerais State. A randomized-block design with three replications in a 2x5 factorial arrangement with two nitrogen sources (urea - 44% and ammonium nitrate - 32%) and five doses (0, 40, 80, 120 and 160 kg.ha -1de N) was used. The application of urea or ammonium nitrate in the studied doses had not influence on the leaf nitrogen contents, sugarcane ratoon yield or the sugar cane chemical-technological characteristics.