Grain yield (Mg ha⁻¹) as affected by main effects of P application and subplot effects of cropping system in 2011 and 2012.

Values are means of three replicates. Values followed by the same lowercase letters are not significantly different among different cropping systems with the same P rate in one year at the 5% level by LSD (horizonal comparison); values followed by the same capital letters are not significantly different among different P rates (vertical comparison) or among different cropping systems (horizonal comparison) in one year at the 5% level by LSD. Values under ANOVA are the probabilities (P values) of the sources of variation. Grain yield (Mg ha−1) as affected by main effects of P application and subplot effects of cropping system in 2011 and 2012.