Resposta da cana-de-açúcar irrigada sob diferentes níveis de adubação.

Abstract

The objective of this work was to study the sugar-cane yield irrigated with different levels of fertilization. If had been studied growth parameters: length, diameter and number of bonds in the culms, culms weight and the technological parameters: the sugarcane industrial fiber, rate of sugar (POL), soluble solids (°Brix), juice purity, rates of sugar in the culms (PCC), culms production, gross yield of sugar ard alcohol. The irrigation system used was central pivot, with total water depth of 27,5mm each 12 days. The total water depth applied in the experiment, represents the irrigation in the alcohol plant, 52% of the total necessity for the region, witch means a supplementary irrigation. The parcel of land had 1,0 x 12,0 m with fine lines. The variety studied was SP 71 6949, planted in August 2000 and gathered in September 2001. It was used randomized blocks with four treatments and there repetitions, it means that it was applied four levels of covering fertilization (Ni, N2, N3, N4). The results showed that the sugar and alcohol production increased, and in the liquid rate, too, when the levels of nutrients (N, P2O5, K20) increased. We concluded that the N2 treatment showed the best cost-efficiency by monetary unit applied.