Ultraviolet-B Radiation and Nitrogen Affect Nutrient Concentrations and the Amount of Nutrients Acquired by Above-Ground Organs of Maize
Table 3
Interactive effects of UV-B radiation and nitrogen on P concentration (mg g−1) and P acquired (g m−2) by above-ground organs of maize.
Nitrogen
Radiation
Silking
Maturity
Lc
Sc
La
Sa
Lc
Sc
Gc
La
Sa
Ga
N0
UV
3.19
2.87
0.48
0.83
2.56
0.99 b
3.27
0.42
0.62
2.19 a
C
3.23
2.73
0.54
0.88
2.72
1.87 a
3.05
0.53
1.18
2.60 a
Mean
3.21
2.80
0.51 C
0.85 C
2.64
1.43 A
3.16
0.48 C
0.90
2.39 D
N1
UV
3.49
2.77
0.51
0.95
2.52
0.86 b
3.20
0.50
0.58
2.92 b
C
3.33
2.82
0.69
1.50
2.80
1.19 a
3.39
0.68
1.13
4.24 a
Mean
3.41
2.80
0.60 BC
1.22 B
2.66
1.02 B
3.30
0.59 BC
0.85
3.58 C
N2
UV
3.38
3.05
0.55
1.18
2.27
1.00 a
3.07
0.50
0.77
3.12 b
C
3.39
2.85
0.80
1.81
2.93
1.22 a
3.59
0.87
1.31
5.36 a
Mean
3.38
2.95
0.68 AB
1.49 A
2.60
1.11 B
3.33
0.68 B
1.04
4.24 B
N3
UV
3.38
2.90
0.67
1.33
2.52
0.95 a
3.06
0.59
0.84
3.42 b
C
3.22
2.46
0.89
1.56
3.15
1.02 a
3.61
1.05
1.22
6.05 a
Mean
3.30
2.68
0.78 A
1.44 A
2.84
0.99 B
3.33
0.82 A
1.03
4.73 A
Mean
UV
3.37
2.88
0.56 b
1.09 b
2.48 b
0.94 b
3.15 b
0.51 b
0.70 b
2.97 b
C
3.29
2.71
0.73 a
1.44 a
2.90 a
1.33 a
3.41 a
0.78 a
1.21 a
4.57 a
ANOVA
Radiation (R)
ns
ns
***
***
*
**
+
***
***
***
Nitrogen (N)
ns
ns
***
***
ns
+
ns
**
ns
***
R × N
ns
ns
ns
ns
ns
+
ns
ns
ns
***
Lc: leaf concentration; Sc: stem concentration; La: amount on leaves; Sa: amount on stems; Gc: grain concentration; Ga: amount on grains; UV: high UV-B treatment; C: ambient UV-B treatment; N0, N1, N2, N3: 0, 100, 200, and 300 kg N ha−1. Means within each N level followed by the same letter (capital letters for N effects within each column) were not significantly different at . Significance of main effects: ns: not significant; +; *; **; ***.
