Objective The study was carried out to explore the effects of cutting seedlings on the growth and yield of maize under substrate covered no-tillage sowing, which would provided reference for improving maize yield under this sowing mode.

Method The 'Huiyutian 3' was used as the experimental material, and the split plot design was adopted for studying the effects of cutting seedlings on growth, development traits and yield of maize under substrate covered no-tillage sowing. The main plot was four different planting densities (6.0×10⁴, 7.0×10⁴, 8.0×10⁴, 9.0×10⁴ plants/hm², respectively marked as A1-A4), the subplot was four different cutting treatments (3-4 leaf age, 5-6 leaf age, 7-8 leaf age, respectively marked as T1-T3), and the control without cutting seedlings was CK.

Result Cutting seedlings had no significant effect on growth cycle and the SPAD value of leaves in the filling stage of maize under substrate covered no-tillage sowing. With the increase of planting density, stem traits and ear traits showed a downward trend. Under the planting density of A1-A3, with the increase of planting density, the yield of maize increased, and the yield of maize decreased relatively under the planting density of A4. The plant height and ear height were significantly reduced, and the stem thick were significantly increased by cutting seedling under A1-A4 planting density, the effect was T2 > T1 > T3. Similarly, the spike length, spike diameter, kernel rows, row grains, panicle weight and yield were improved by cutting seedling under A1-A4 planting density, and the effect of T2 was the best. Compared with CK, the average yield of A1-A4 planting density under T2 treatment increased by 3.80%, 11.71%, 15.49% and 13.24%, respectively. Under A3 planting density, the effect of cutting seedling treatment on promoting yield was significantly better than that of other planting densities, and the yield of T1-T3 treatment increased by 13.53%, 15.49% and 8.98%, respectively.

Conclusion Cutting seedlings could reduce the center of gravity and improve stem diameter of maize under substrate covered no-tillage sowing. Furthermore, it promoted the positive growth and development of ear traits such as ear length, ear diameter, row number per ear, grain number per row and grain mass per ear, and effectively improved the yield under substrate covered no-tillage sowing. Under the planting density of 8.0×10⁴ plants/hm², the effect of cutting seedlings at 5-6 leaf ages was the best.