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Table I
Mean values (± SE) of morphological parameters of red pine seedlings after the first growing season. Seedlings were fall fertilized with a single application of ammonium nitrate (NH4 NO3) at rates of 0, 11, 22, 44 and 89 kg N ha−1. For each parameter, values in the same row with different letters differed statistically according to Fisher’s Least Significant Difference test at α = 0.05.
Fall fertilizer application rate (kg N ha−1) | |||||
---|---|---|---|---|---|
0 | 11 | 22 | 44 | 89 | |
Height (cm) | 6.07 (0.57)b | 5.70 (0.48)b | 5.95 (0.42)b | 6.4 (0.26)ab | 7.45 (0.15)a |
RCD (mm) | 1.70 (0.07)a | 1.50 (0.04)a | 1.55 (0.18)a | 1.70 (0.14)a | 1.80 (0.13)a |
Shoot dry mass (g) | 0.64 (0.05)ab | 0.47 (0.09)b | 0.61 (0.20)ab | 0.81 (0.13)ab | 0.98 (0.10)a |
Root dry mass (g) | 0.19 (0.02)a | 0.21 (0.03)a | 0.18 (0.03)a | 0.20 (0.02)a | 0.25 (0.01)a |
Shoot N conc. (%) | 1.66 (0.12)c | 2.06 (0.08)b | 2.04 (0.08)b | 2.15 (0.04)ab | 2.33 (0.04)a |
Root N conc. (%) | 0.92 (0.09)b | 1.18 (0.03)ab | 0.97 (0.32)b | 1.34 (0.02)ab | 1.55 (0.14)a |
Shoot N cont. (mg) | 10.61 (0.48)b | 9.74 (2.01)b | 12.64 (4.41)b | 17.47 (2.97)ab | 22.98 (2.05)a |
Root N cont. (mg) | 1.87 (0.40)b | 2.51 (0.32)ab | 1.74 (0.73)b | 2.79 (0.37)ab | 3.86 (0.27)a |
Number of needle primordia | 17.0 (0.8)c | 19.2 (0.7)c | 17.7 (0.9)c | 25.0 (1.4)b | 31.7 (1.0)a |