Table 5.
Coefficients of determination (R2) of relationships obtained from simple regression analysis of the green pixel percentage obtained from the image analysis with the destructively obtained parameters nitrogen uptake, nitrogen concentration, biomass fresh and dry weight of wheat at individual measurements and for the combined measurements.
| Dates | BBCH | Nitrogen uptake (kg ha-1) | Nitrogen concentration (%) | Biomass fresh weight (kg ha-1) | Biomass dry weight (kg ha-1) |
|---|---|---|---|---|---|
| 04.03.2014 | 19 | 0.61∗∗∗ | 0.10∗∗ | 0.56∗∗∗ | 0.48∗∗∗ |
| 17.03.2014 | 22 | 0.85∗∗∗ | 0.06∗ | 0.88∗∗∗ | 0.71∗∗∗ |
| 01.04.2014 | 25 | 0.81∗∗∗ | 0.19∗∗∗ | 0.89∗∗∗ | 0.81∗∗∗ |
| 14.04.2014 | 30 | 0.75∗∗∗ | 0.30∗∗∗ | 0.81∗∗∗ | 0.68∗∗∗ |
| All dates | 0.84∗∗∗ | 0.15∗∗∗ | 0.83∗∗∗ | 0.82∗∗∗ | |
∗, ∗∗, ∗∗∗ Statistically significant at P ≤ 0.05, P ≤ 0.01, and P ≤ 0.001, respectively.