| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4465340 | International Journal of Applied Earth Observation and Geoinformation | 2010 | 6 Pages |
The aim of this study was to explore the use of in situ spectroscopy for estimating sugarcane leaf nitrogen (N) concentration. Leaf spectral reflectance was measured using a field spectroradiometer in the 350–2500 nm range from sugarcane variety N19 crops of 6–7 months old under on-farm conditions. Lab-determined leaf N concentrations of the samples taken ranged from 1.00% to 1.55%. Vegetation indices based on simple ratio (SR); viz. SR (743, 1316), SR (743, 1317) and SR (741, 1323) generated from first-order derivatives of leaf reflectance showed the best correlation with leaf N concentration, with r2 values of 0.76 (P < 0.01), 0.75 (P < 0.01) and 0.74 (P < 0.01), respectively. The root mean square errors of prediction (RMSEP) using a leave-one-out cross validation method were 0.089% (P < 0.01) for SR (743, 1316), 0.092% (P < 0.01) for SR (743, 317) and 0.084% (P < 0.01) for SR (741, 1323). These results suggest that the in situ spectroscopy has potential use in predicting sugarcane leaf N.
