Ultraviolet-B Radiation and Nitrogen Affect Nutrient Concentrations and the Amount of Nutrients Acquired by Above-Ground Organs of Maize
Table 6
Interactive effects of UV-B radiation and nitrogen on Mg concentration (mg g−1) and Mg 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
2.40
2.80
0.35
0.82
3.00
2.08 a
1.22
0.49
1.30
0.82 a
C
3.24
3.17
0.53
1.05
3.03
2.05 a
1.03
0.58
1.32
0.88 a
Mean
2.82
2.99 B
0.44
0.94 C
3.01
2.07
1.12
0.53 B
1.31 C
0.85 C
N1
UV
3.23
3.51
0.47
1.19
3.13
2.03 a
1.25
0.62
1.37
1.15 b
C
4.29
3.51
0.90
1.87
3.05
1.75 a
1.12
0.75
1.68
1.39 a
Mean
3.76
3.51 A
0.68
1.53 B
3.09
1.89
1.19
0.68 AB
1.53 BC
1.27 B
N2
UV
2.64
2.78
0.44
1.07
3.32
2.42 a
0.96
0.73
1.84
0.98 b
C
3.09
2.83
0.74
1.79
2.55
1.49 b
1.21
0.76
1.61
1.78 a
Mean
2.86
2.80 B
0.59
1.43 B
2.93
1.96
1.09
0.74 A
1.73 AB
1.38 B
N3
UV
2.64
3.20
0.51
1.47
3.17
2.08 a
1.17
0.74
1.84
1.30 b
C
2.67
3.47
0.73
2.21
2.37
1.51 b
1.28
0.79
1.81
2.15 a
Mean
2.65
3.33 A
0.62
1.84 A
2.77
1.79
1.23
0.77 A
1.82 A
1.73 A
Mean
UV
2.77
3.13
0.45 b
1.17 b
3.16 a
2.13 a
1.16
0.65
1.59
1.10 b
C
3.32
3.24
0.73 a
1.72 a
2.75 b
1.70 b
1.16
0.72
1.60
1.56 a
ANOVA
Radiation (R)
ns
ns
**
***
+
**
ns
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, +, **, ***.
