September 14, 2023 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy |
Researchers from King Mongkut's Institute of Technology Ladkrabang, Thailand, and Nagoya University, Japan, investigated a rapid, non-destructive method for evaluating nutrient content in durian leaves using near-infrared spectroscopy (NIR). Traditional methods for assessing nutrient concentrations in leaves are time-consuming, limiting timely fertilization adjustments by farmers. This study employed Fourier transform near-infrared (FT-NIR) spectroscopy to scan fresh, dried ground, and pelletized durian leaf samples, covering wavelengths between 12,500–3,600 cm⁻¹.
The team developed regression models using partial least squares (PLS) with different wavelength selections, including a successive projections algorithm (SPA). The models for predicting nitrogen (N) and potassium (K) concentrations performed well, while phosphorus (P) predictions were less successful. The best model for N content used fresh leaves (r² = 0.852), and the best model for K content used dried ground leaves (r² = 0.820). The study found that NIR could effectively predict N and K concentrations based on the bonding of proteins formed by these nutrients, rather than direct wavelength associations.
This research demonstrates the potential for applying NIR spectroscopy to quickly assess nutrient levels in durian leaves, enabling farmers to make immediate, data-driven fertilization decisions to optimize crop quality.
