TABLE 1.
Two-way analysis of variance of the plant traits in 2018 and 2019 under control, drought, genotypes, and genotype × treatment interaction, at the end of water stress application.
| Traits | 2018 |
2019 |
||||||||
| Control | Drought | Treatment | Genotype | G × T | Control | Drought | Treatment | Genotype | G × T | |
| Plant height (cm) | 92.9 | 75.9 | *** | NS | NS | 93.3 | 67.8 | *** | *** | NS |
| Tiller number | 17.50 | 13.97 | *** | NS | NS | 21.40 | 11.39 | *** | * | NS |
| Wilting/drought score | 0.00 | 2.85 | *** | *** | NA | 0.07 | 3.36 | *** | *** | NA |
| Relative leaf water content (%) | 87.5 | 74.4 | *** | *** | *** | 85.9 | 55.7 | *** | *** | *** |
| Spike number | 18.35 | 10.00 | *** | *** | * | 26.40 | 16.39 | *** | *** | *** |
| Grain weight/plant (g) | 12.57 | 2.91 | *** | *** | *** | 14.22 | 4.37 | *** | *** | *** |
| Grain number per the main tiller | 25.27 | 18 | *** | *** | NS | 28.84 | 11.05 | *** | *** | *** |
| Length of the main spike (cm) | 10.61 | 8.68 | *** | *** | NS | 10.01 | 7.82 | *** | *** | *** |
| Shoot fresh weight (g) | 59.01 | 46.13 | *** | *** | ** | 35.8 | 19.9 | *** | *** | NS |
| Shoot dry weight (g) | 27.63 | 23.56 | *** | *** | ** | 18.22 | 12.15 | *** | *** | * |
| Root dry weight (g) | 4.99 | 3.91 | *** | *** | NS | 3.99 | 2.91 | *** | *** | NS |
| Root/shoot ratio (g) | 0.18 | 0.17 | NS | NS | NS | 0.22 | 0.24 | NS | NS | NS |
| A (μmol m–2 s–1) | 28.83 | 13.13 | *** | *** | *** | 21.51 | 6.08 | *** | *** | *** |
| E (mol m–2 s–1) | 9.9E–3 | 3.6E–3 | *** | *** | *** | 9E–3 | 2E–3 | *** | *** | *** |
| Ci (μmol mol–1) | 260.86 | 176.54 | *** | *** | *** | 239 | 216 | * | NS | NS |
| VPDleaf | 2.34 | 3.19 | *** | *** | *** | 2.22 | 2.32 | *** | NS | NS |
| gsw (mol m–2 s–1) | 0.43 | 0.11 | *** | *** | *** | 0.28 | 0.063 | *** | *** | *** |
| iWUE (μmol CO2 mmol–1 H2O) | 68 | 118 | *** | NS | * | 81 | 95 | *** | *** | *** |
| ETR (μmol m–2 s–1) | 163 | 99 | *** | *** | *** | 139 | 100 | *** | *** | *** |
| Leaf proline (μg/g FW) | 63 | 325 | *** | *** | *** | 43 | 299 | *** | *** | *** |
| Spike proline (μg/g FW) | – | – | – | – | – | 120 | 580 | *** | *** | *** |
“*, **, and ***” – Follows the standard probability values (P ≤ 0.05, P ≤ 0.01, or P ≤ 0.001). Means of A, E, Ci, VPDleaf, gsw, iWUE, ETR, and proline were back-transformed to original values after transformation. A, net CO2 assimilation; E, transpiration; gsw, stomatal conductance; VPDleaf, vapor pressure deficit of the leaf; iWUE, intrinsic water use; efficiency, A/gsw; ETR, electron transport rate; FW, fresh weight; NA, not analyzed; NS, not significant.