Effect of nitrogen and potassium fertilization on the growth of the second ratoon of sugarcane

Abstract

The objective of this study was to evaluate the influence of nitrogen and potassium fertilization on some biometric variables of the second sugarcane ratoon. The experiment was conducted in pots containing Dystrophic Red Latosol, implanted in an experimental area of the Goiano Federal Institute Campus Rio Verde, GO. The experimental design was a randomized block design, with three replications, analyzed in a 2×5 factorial scheme, being that treatments was with and without nitrogen fertilization (0 e 120 kg of N/ha), combined with five potassium rates (0, 60, 120, 180 e 240 kg ha^‑1). The biometric variables plant height, leaf length and number, number of plants, stalk length and diameter, stalk number and mean stalk length were determined at 150, 190, 230 and 270 days after the cut. The application of nitrogen increased leaf length, but limited the amount of leaves per plant. As for the average stalk length and plant height, there were only increases with nitrogen use without the presence of potassium fertilization. Potassium yielded increases in plant height when there was no fertilization with N, while for the stalk diameter the 240 kg ha^‑1 dose obtained the highest value when associated with nitrogen fertilization.