N rate (kg N ha⁻¹)

Mean Plant N Concentration (%)

Parma

Ashton

Rupert

0

0.76d

0.76a

1.31.b

84

1.05c

0.80a

1.41b

168

1.18b

0.79a

1.44ab

252

1.17b

0.83a

1.39b

336

1.32a

0.82a

1.58a