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| Author(s): |
Hugo Miranda Faria
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Jaboticabal. 2022-03-15. |
| Institution: | Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal |
| Defense date: | 2021-07-07 |
| Advisor: | Jose Eduardo Corá |
| Abstract | |
Sugarcane is a crop of paramount importance for the Brazilian economy, with the planted area growing annually. Sugarcane cultivation requires a high amount of nutrients, mainly nitrogen, for the plant to develop properly. This study aimed to evaluate the effect of nitrogen rates and fertilizer application times on dry matter production and accumulated N in sugarcane biomass, yield, and total recoverable sugar (TRS) during two years of sugarcane cultivation (2nd and 3rd ratoon) in the crop cycle. The experiment was conducted in a commercial sugarcane area located in the State of São Paulo, Brazil (21°22′38.48″S, 47°57′28.01″W). The experiment was set up in a 4x3 factorial scheme plus the control treatment, distributed in randomized blocks with four replications. Two applications of nitrogen fertilizer were carried out. The first application was carried out right after harvest and the second application was performed when the crop was approximately 1.10 m high. The treatments consisted of four nitrogen rates (54, 109, 163, and 218 kg N ha−1) plus the control (0 kg N ha−1) and three application times, as follows: 1) application of all the fertilizer in the first application; 2) split N application, the first half of the rate in the first application and the other half in the second application; and 3) application of all fertilizer in the second application. The cultivar RB85-5156 was used in the experiment. Dry matter (DM) and accumulated N of the sugarcane shoot (biomass), divided into top and stalk, TRS, and yield were analyzed in two years of cultivation (2018/2019 and 2019/2020), during the sugarcane cycle. Higher amounts of DM and N accumulated in the tops, stalk, and biomass were observed after the second application of nitrogen fertilizer, when a crop was approximately 1.10 m high, a period with a high precipitation. No statistical difference was observed for sugarcane yield between the evaluated treatments. However, a higher amount of TRS was observed in the first agricultural year, when all the fertilizer was applied when the crop was approximately 1.10 m high. The number of rainy days per sugarcane sampling period was decisive for biomass production and yield. (AU) | |
| FAPESP's process: | 17/18418-2 - Improving nitrogen use efficiency in sugarcane using remote sensing data linked to crop modeling and yield mapping technologies |
| Grantee: | Hugo Miranda Faria |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |