Residual effect of different summer cropping systems on yield of winter wheat and soil nitrate-N accumulation (0–100 cm) after harvest of wheat in Experiment 2.

<p>Note: Different letters represented significant differences between means of replicates (n = 3) at the 0.05% level within a column.</p><p>Residual effect of different summer cropping systems on yield of winter wheat and soil nitrate-N accumulation (0–100 cm) after harvest of wheat in Experiment 2.