Incidence of Red Rot in Productivity and Quality On Sugar Cane in Function of Diferent Doses of Nitrogen.

The present study aimed to evaluate the effect of the fertirrigation fertilization by means of subsurface drip, on the incidence and the damage caused by red rot on productivity and quality in sugarcane (SP80-3280). The experiment was carried in Research and Development Unit of APTA to Jau-SP, in a randomized block design (RBD), consisting of five doses of N-fertilizer, in irrigation system drip irrigation: (1) 0 N-fertilizer (control); (2) 50 kg ha^-1 of N-fertilizer; (3) 100 kg ha^-1 of N-fertilizer; (4) 150 kg ha^-1 of N-fertilizer and (5) 200 kg ha^-1 of N-fertilizer. In the field, the parameters evaluated were:percentage of incidence of red rot.  During the evaluations, it was determined the stalk productivity and the sugar content of the treatments. It was observed that the fertirrigation fertilization increases the red rot. However, the productivity of stalks and sugar increased with the nitrogen fertilization, justifying the application of higher doses of nitrogen. The biggest financial yield was obtained with the dose of 150 kg ha^-1 of N-fertilizer.