Impact of Nitrogen and Sulphur Fertilisers on Yield and Quality of Sugarcane Plant Crop

Abstract

It is expected that an improvement in nitrogen (N) uptake by plants would occur if sulphur (S) availability in the soil solution is non-limiting. In this study, sugarcane (plant crop) responses to N were studied at different levels of S application. The experiment was performed in Piracicaba city (Sao Paulo State, Brazil), from May 2004 to September 2005. Sugarcane plants were grown in 220 L pots filled with sandy soil. A randomised block design was adopted to evaluate four N doses (0, 40, 80 and 120 kg ha−1 of N) and two S doses (0 and 70 kg ha−1 of S) applied at the time of planting. Responses were observed for sugarcane biomass and stalk production in response to N application 16 months after the planting. The highest N dose (120 kg ha−1) increased aboveground, belowground, and whole plant dry matter and stalk production by 56, 37, 53 and 56 %, respectively, when compared to the treatment without added N. The lowest N doses (0 and 40 kg ha−1) resulted in highest root to shoot ratio. The sugarcane technological parameters (brix, fiber content, juice sucrose) were not affected by N and S application. However, sugar production increased in those doses of N that led to an increased production of stalks: even the lowest application of N (40 kg ha−1) increased sugar production by 14 % in comparison with the zero application. There were no statistically significant effects of the S treatment, so the results of this study do not confirm the hypothesis that S is an interacting factor for sugarcane response to N application. However, this study involved only 1 year of experimentation and needs confirmation.