Assessment of Nitrogen Fertilization in Sugarcane Using Multispectral Photogrammetry

Sugarcane agriculture, fundamental for many tropical economies, faces the challenge of balancing expansion with biodiversity preservation and economic viability. This study examines the impact level of nitrogen fertilizers in the C 86-12 cane variety via multispectral photogrammetry, using a long-term experiment with different nitrogen doses. Thirteen vegetation indices (VIs) were analyzed to assess their sensitivity to nitrogen levels in experimental plots. Samples from 6 to 10-month-old crops were collected using a multispectral camera, generating indices maps through Pix4D software. The correlation between VI values and applied nitrogen levels was evaluated using Kendall and Spearman methods. The results revealed a varied responsiveness of the indices to nitrogen levels, observing little correlation between nitrogen fertilization and sugarcane vigor in the early stages after planting. Additionally, it was observed that as the number of cuts made to the sugarcane plant increases, the efficiency of nitrogen fertilization improves, allowing for higher yields in tons of cane per kilogram of applied nitrogen. Future research should further explore the factors influencing nitrogen utilization and refine management strategies to optimize yield and sustainability in sugarcane agriculture, addressing the industry’s environmental and economic challenges.