Table 8: Interactive effects of UV-B radiation and nitrogen on Cu concentration (μg g−1) and Cu acquired (mg m−2) by above-ground organs of maize.

NitrogenRadiationSilkingMaturity
LcScLaSaLcScGcLaSaGa

N0UV11.502.001.790.5717.5 a6.002.002.88 a3.781.34
C9.673.00 1.590.9811.7 b6.001.332.26 a3.581.14
Mean10.592.50 B 1.690.78 B 14.6 B6.001.672.57 C3.68 B1.24 B

N1UV14.003.332.061.1214.3 b3.671.672.84 b2.581.55
C14.333.002.991.6019.0 a5.331.334.63 a5.191.66
Mean14.173.16 B2.521.36 B16.7 B4.501.503.73 B3.89 B1.60 B

N2UV12.003.502.001.3718.5 b5.001.504.05 b3.771.52
C11.003.672.552.3224.3 a5.001.337.20 a5.321.95
Mean11.503.59 AB2.271.85 AB21.4 A5.001.425.63 A4.54 AB1.73 B

N3UV14.337.002.943.2522.0 a5.332.335.10 b4.792.67
C10.674.002.922.5422.7 a5.671.677.53 a6.842.78
Mean12.505.50 A2.932.90 A22.3 A5.502.006.32 A5.81 A2.72 A

MeanUV13.204.202.261.7018.14.901.90 a3.77 b3.72 b1.84
C11.423.422.511.8619.45.501.42 b5.41 a5.23 a1.88

ANOVA

Radiation (R)nsnsnsnsnsns+ *** * ns
Nitrogen (N)ns+ns * ** nsns *** + *
R × Nnsnsnsns * nsns ** nsns

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 𝑃 < 0 . 1 0 . Significance of main effects: ns: not significant, + 𝑃 < 0 . 1 , * 𝑃 < 0 . 0 5 , ** 𝑃 < 0 . 0 1 , *** 𝑃 < 0 . 0 0 1 .