Fertilizer treatment

Yield (kg·ha⁻¹)

Grain Protein Content (g·kg⁻¹)

2011

2012

2013

2011

2012

2013

75% optimal N rate

2 819 a

3 456 a

3 220 a

151 c

150 c

140 c

75% optimal N rate +

33 kg·ha⁻¹ PA^b

2 667 ab

3 302 a

3 011 b

159 a

156 a

146 a

75% optimal N rate +

33 kg·ha⁻¹ PP^c

2 638 b

3 419 a

3 210 a

155 b

152 b

145 b