Table 1.
Mean grain yield, its components, and harvest index as affected by different CO2 concentrations and genotypes averaged for two years (2012 and 2013).
| CO2 Concentration | Genotype | Grain Yield (g m−2) | Spikelet number (× 103 m−2) | Panicle number (m−2) | Spikelet number (panicle−1) | Percentage of filled spikelets (%) | 1000-grain weight (g) | Harvest Index |
|---|---|---|---|---|---|---|---|---|
| CO2 concentration (C) | ||||||||
| FACE | 813 | 47.0 | 333 | 143 | 85.4 | 20.5 | 0.41 | |
| Ambient | 702 | 44.4 | 326 | 138 | 77.6 | 20.6 | 0.40 | |
| Genotype (G) | ||||||||
| Koshihikari | 735b† | 40.5c | 358a | 113c | 86.5a | 21.0a | 0.39b | |
| CSSL-GN1 | 724b | 51.3a | 322b | 160a | 72.9b | 19.4b | 0.39b | |
| NIL-APO1 | 814a | 45.3b | 308b | 147b | 85.0a | 21.1a | 0.43a | |
| C × G | ||||||||
| FACE | Koshihikari | 763b | 40.6 | 358 | 114 | 89.2 | 21.1 | 0.40b |
| CSSL-GN1 | 791abA‡ | 53.4 | 328 | 163 | 78.0 | 19.1 | 0.40bA | |
| NIL-APO1 | 886aA | 47.0 | 313 | 151 | 89.0 | 21.2 | 0.43a | |
| Ambient | Koshihikari | 708ab | 40.3 | 359 | 113 | 83.9 | 21.0 | 0.39b |
| CSSL-GN1 | 656bB | 49.3 | 316 | 157 | 67.7 | 19.7 | 0.38cB | |
| NIL-APO1 | 743aB | 43.5 | 304 | 144 | 81.0 | 21.1 | 0.42a | |
| ANOVA | ||||||||
| CO2 concentration (C) | NS¶ | NS | NS | NS | ** | NS | § | |
| Genotype (G) | ** | ** | ** | ** | ** | ** | ** | |
| C × G | * | NS | NS | NS | NS | ** | § | |
*Significant at P < 0.05. **Significant at P < 0.01. †Means within a column followed by the same lowercase letter do not differ significantly (P < 0.05). ‡Means within a column followed by the same lowercase letter do not differ significantly (P < 0.05) among genotypes for a given CO2 concentration. Means within a column followed by the same uppercase letter do not differ significantly (P < 0.05) between CO2 concentrations for a given genotype. §Significant at P < 0.10. ¶Not significant at P < 0.10.