Figure 7
Harvest index of wheat and maize in sole and intercropping systems with different N management practices in 2018–2020. I, intercropping, S, sole cropping. For intercropping system, N1, N2, and N3 represent N-fertilizer applied at 51, 72, and 93 kg N ha−1 as first top-dressing plus 63, 42, and 21 kg N ha−1 at third top-dressing, respectively. For sole maize, N1, N2 and N3 represent N-fertilizer applied at 36, 72, and 108 kg N ha−1 as first top-dressing plus 108, 72, and 36 kg N ha−1 at third top-dressing, respectively. For sole wheat, N1 represents the N-fertilizer applied at 108 kg N ha−1 as base fertilizer at sowing plus 72 kg N ha−1 top-dressed at pre-tasseling. Different lowercase above bars indicates significant difference (P ≤ 0.05) among different N managements. Error bars indicates standard error of the means (n = 3).
