TABLE 2.
Effect of planting density and nitrogen application on grain filling parameters of maize in 2015 and 2016.
| Year | Planting density | N level | Wmax | Tmax | Gmax | P | Gmean | T1 |
| (g 100-kernel–1) | (d) | (g d–1 100-kernel–1) | (d) | (g d–1 100-kernel–1) | (d) | |||
| 2015 | ND | N0 | 11.87d | 28.02c | 1.76d | 40.41c | 0.29d | 19.15b |
| N150 | 15.77b | 26.13d | 2.14b | 44.24b | 0.36b | 16.42d | ||
| N300 | 17.93a | 26.20d | 2.36a | 45.55b | 0.39a | 16.20d | ||
| HD | N0 | 10.71e | 33.53a | 1.61e | 40.04c | 0.27e | 24.74a | |
| N150 | 14.71c | 28.93b | 2.00c | 44.25b | 0.33c | 19.21b | ||
| N300 | 17.66a | 28.25bc | 2.21b | 47.97a | 0.37b | 17.71c | ||
| 2016 | ND | N0 | 11.37d | 28.53a | 1.86e | 36.62c | 0.31e | 20.49a |
| N150 | 14.37c | 22.18d | 2.29c | 37.62bc | 0.38c | 13.93bc | ||
| N300 | 18.28a | 22.98bc | 2.61a | 42.82a | 0.43a | 13.75c | ||
| HD | N0 | 10.88d | 28.81a | 1.65f | 39.60bc | 0.27f | 20.12a | |
| N150 | 13.90c | 23.07bc | 2.15d | 38.79bc | 0.36d | 14.56b | ||
| N300 | 16.91b | 23.35b | 2.46b | 41.29ab | 0.41b | 14.31bc | ||
| ANOVA | ||||||||
| Year (Y) | *** | *** | *** | *** | *** | *** | ||
| Plant density (D) | *** | *** | *** | *** | *** | *** | ||
| N level (N) | *** | *** | *** | * | *** | *** | ||
| D × N | ns | *** | ns | ns | ns | *** | ||
| Y × D × N | * | *** | ns | *** | * | *** | ||
Wmax, the kernel weight increment achieving maximum grain-filling rate; Tmax, the day reaching the maximum grain-filling rate; Gmax, the maximum filling rate; P, the active grain filling phase; Gmean, the mean grain-filling rate; T1, the lag period. ND and HD indicate planting density of 67,500 and 90,000 plants ha–1; N0, N150, and N300 indicate N applied at 0, 150, and 300 kg ha–1 levels, respectively. Values of six treatments followed by different letters indicate significant difference at 5% level. ns, no significance; *, **, and *** indicate significance at 5%, 1%, and 0.1% level, respectively.