Techniques of precision agriculture are alternatives to optimize the use of inputs, among them nitrogen. The present work had as its objective to verify the possibility of use of a commercial optical sensor in sugarcane, verifying its capability in identification of the crop response to different nitrogen (N) rates. An experiment was installed in randomized blocks in an experimental area with third sugarcane ratoon, harvested mechanically, with different N rates (0, 50, 100, 150 and 200 kg ha-1) and four repetitions. At 30, 60 and 90 days after the harvest (DAH) the measuring of NDVI (normalized difference vegetation index) was accomplished starting from the optical sensor. No response was verified of NDVI on measurements at the 30 and 60 DAH, however at 90 DAH the sensor was capable to differentiate the doses of applied N, positively correlated with the sugarcane final production. This work gives subsidies to studies of same nature that seek the management of the nitrogen fertilization in sugarcane using optical sensor.
precision agriculture; remote sensing; NDVI