Urea- Versus Ammonium Nitrate–Based Fertilizers for Green Sugarcane Cultivation

• Published in: Journal of soil science and plant nutrition 2021-06, Vol.21 (2), p.1329-1338
• Main Authors: Moreira, Lílian Angélica, Otto, Rafael, Cantarella, Heitor, Junior, Jose Lavres, Azevedo, Ricardo Antunes, de Mira, Acácio Bezerra
• Format: Article
• Language: English
• Subjects: Agricultural production; Agriculture; Ammonia; Ammonium; Ammonium nitrate; Biodiesel fuels; Biofuels; Biomedical and Life Sciences; Crop yield; Cultivation; Design of experiments; Ecology; Emissions; Environment; Ethanol; Experimental design; Fertilization; Fertilizers; Fossil fuels; Glutamate-ammonia ligase; Glutamine; Life Sciences; Metabolism; Nitrate reductase; Nitrates; Nitrogen; Original Paper; Plant Sciences; Potassium; Reductases; Soil Science & Conservation; Sugar; Sugarcane; Urea; Ureas; Urease
• ISSN: 0718-9508; 0718-9516
• DOI: 10.1007/s42729-021-00443-x

This study tested the hypothesis that enhanced-efficiency fertilizers, such as urea treated with NBPT, are a feasible substitute for ammonium nitrate–based fertilizers for green sugarcane cultivation. The experimental design included six N sources applied over sugarcane straw at two sites in Central-South Brazil. Treatments included ammonium nitrate, urea, and four urea-based fertilizers treated with different rates of the urease inhibitor N-(n-butyl)thiophosphoric triamide (NBPT) at two rates of N (50 and 100 kg ha −1 ), plus an additional control. Nitrogen status in the plant, the activity of glutamine synthetase (GS) and nitrate reductase (NR) in the leaves, and sugarcane stalk yield and quality were evaluated. At site 1, N rates increased the SPAD index, stalk yield, N uptake, and sugar yield. At site 2, N rates increased GS activity, N content, the SPAD index, and N uptake, but stalk and sugar yield were not increased due to large variability in these parameters. All N sources resulted in similar yields at both sites. These results were compared with those in the literature. Among 27 studies surveyed, the average sugarcane yield was 97.8 or 97.4 Mg ha −1 under ammonium nitrate or urea fertilization, respectively, and these averages did not differ by the Kruskal-Wallis test. The results of this study demonstrate that enhanced-efficiency fertilizers have the potential to reduce NH 3 emissions from urea-based fertilizers in green sugarcane fields without affecting sugarcane yield.