Table II. Summary of the ANCOVA model (F values and degrees of freedom) of shoot traits at 28 d after planting as influenced by CN and N treatment in six maize RILs in greenhouse mesocosms.
*P < 0.05, **P < 0.01, ***P < 0.001, ****P = 0.1. Degrees of freedom are shown as (numerator, denominator).
| Effect | Shoot Weight | Photosynthesis Rate | Carbon Assimilation | Tissue N Content |
|---|---|---|---|---|
| CN | 22.31 (1, 43)*** | 9.48 (1, 43)** | 6.51 (1, 43)* | 16.55 (1, 44)*** |
| N treatment | 23.78 (1, 43)*** | 31.62 (1, 43)*** | 75.66 (1, 43)*** | 29.15 (1, 44)*** |
| CN-N treatment | 4.89 (1, 43)* | 14.08 (1, 43)*** | 0.2 (1, 43) | 2.79 (1, 44)**** |
| r2 | 0.66 | 0.53 | 0.63 | 0.49 |