Table 4.
Linear regression value (R2) and Root Mean Square Error (RMSE) of NDVI derived from Sentinel-2 and Achene yield and Biomass at differtent Sunflower crop growth stages (BBCH scale) and Day After Sowing (DAS).
| Achene yield | Biomass | ||||
|---|---|---|---|---|---|
| Crop Growth Stage BBCH scale (Meier, 2001) | DAS | R2 | RMSE | R2 | RMSE |
| Germination | 8 | 0.02 | 66.7 | 0.01 | 242.6 |
| Leaf Development | 18 | 0.01 | 66.9 | 0.03 | 240.4 |
| Inflorescence development | 53 | 0.63 | 40.9 | 0.61 | 151.9 |
| Inflorescence development | 58 | 0.71 | 36.1 | 0.68 | 137.6 |
| Flowering | 63 | 0.73 | 34.5 | 0.72 | 128.3 |
| Flowering | 68 | 0.72 | 35.6 | 0.69 | 135.1 |
| Development of fruit | 78 | 0.69 | 37.1 | 0.68 | 137.5 |
| Ripening | 88 | 0.63 | 41.0 | 0.69 | 135.4 |
| Ripening | 98 | 0.58 | 43.4 | 0.65 | 143.1 |