Nitrogen fertilization in sugar cane

Sugarcane extracts large amounts of nitrogen (N) from the soil; however, extraction depends on the variety of cane, soil characteristics, climatic conditions and crop management. Evaluations carried out at the Sugarcane Research Center of Colombia (CENICAÑA) with the CC 83-25 variety, harvested at 13 months of age, allowed to determine that for each ton of grinding stalks produced, 1.53 kg of N are extracted from the soil. That is to say, for an average production of 132.4 t/ha, typical of the flat part of the Cauca River valley, the total extraction by the crop can be estimated at 203 kg of N/ha; but since the buds, yaguas and leaves remain in the field as crop residues, the real extraction of N would be 93 kg of N/ha, which corresponds to the nitrogen compounds found in the grinding stalks transported to the factory.

The Colombian sugar industry is located almost entirely in the flat part of the Cauca River valley. Most of its soils are alluvial, clayey-loam and with medium organic matter content; 72% of the soils have organic matter contents between 2 and 4%.

The nutritional demands of sugarcane cultivation and the medium organic matter content of the soils in the Cauca River Valley mean that the greatest limitations in terms of soil fertility are related to N. For this reason, research on sugarcane fertilization carried out in Colombian sugar mills located in the flat part of the Cauca River Valley has been directed towards determining the doses, times and sources of N.
more appropriate for the most important varieties that are planted in the different soil groups in this region.