CRESCIMENTO E RENDIMENTO BRUTO DE AÇÚCAR DA CANA-DE-AÇÚCAR FERTIRRIGADA COM NITROGÊNIO E ZINCO

The objective was to evaluate the gross sugar yield of sugarcane fertirrigated with nitrogen and zinc in sugarcane of second year. The experiment was conducted in field conditions in an area of the Rio Paraiso II farm belonging to the Raízen industry, in the municipality of Jatai-GO. The soil of the experimental area is classified as dystrophic Red Latosol, very clayey. The experimental design used was randomized block, analyzed in factorial scheme 4 x 5, with four replications. The treatments consisted of four nitrogen doses (0, 60, 120 and 180 kg ha) and five doses of zinc (0, 2.5, 5.0, 7.5 and 10 kg ha) in sugarcane of second year. The plots was consisted of 5 lines of sugarcane of 5 m long, spaced 1.50 m apart, constituting 45 m per plot. The area used of plot was 2 central lines of each plot, disregarding 2 m at each end. The variables evaluated was gross sugar yield and plant height. The variety implanted in the experiment was the IACSP 95-5000. The irrigation was realized by a central Pivot, in galvanized steel, low pressure, with 12 support towers, with an area total irrigated of 139.31 ha, velocity of 268 m h in the last tower, applying an amount of water gross minimum of 1.35 mm for a full turn. The crude sugar yield and plant height of the fertirrigated sugarcane with nitrogen and zinc show increments above 18%.