Table 3. Values of leaf relative water content (RWC, %) and water potential (ΨW, MPa).
Values were obtained at predawn along the entire experiment for Apoatã, Icatu, and Obatã genotypes, under well-watered (WW), mild drought (MD) and severe drought (SD) conditions, and submitted to temperature control conditions (25/20 oC), during the gradual temperature decrease (18/13 oC), at the end of the acclimation period (13/8 oC), after 3 chilling cycles (3x13/4 oC), after 7 days under rewarming conditions (7x Rec Cold), and after a further 7 days period under rewatering conditions (7x Rec Drought).
| Genotype | Treatment | Temperature (day/night) | |||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 25/20°C | 18/13°C | 13/8°C | 3x13/4°C | 7x Rec Cold | 7x Rec Drought | ||||||||||||||||||||
| Predawn RWC (%) | |||||||||||||||||||||||||
| WW | 92.1 | ± | 3.3 | aA | 94.5 | ± | 1.4 | aA | 79.2 | ± | 6.8 | bcAB | 73.0 | ± | 5.4 | cA | 90.9 | ± | 0.5 | abA | 91.8 | ± | 0.7 | aA | |
| Apoatã | MD | 88.4 | ± | 2.8 | abAB | 85.0 | ± | 1.5 | abAB | 83.8 | ± | 2.8 | abA | 77.2 | ± | 4.9 | bA | 82.5 | ± | 4.1 | abA | 89.4 | ± | 2.7 | aA |
| SD | 82.9 | ± | 3.1 | abB | 78.2 | ± | 6.5 | abcB | 72.0 | ± | 5.4 | bcB | 69.1 | ± | 6.5 | cA | 82.2 | ± | 3.1 | abA | 84.5 | ± | 2.3 | aA | |
| WW | 92.3 | ± | 1.8 | abA | 88.9 | ± | 2.2 | abA | 87.3 | ± | 2.1 | abA | 81.1 | ± | 3.2 | bA | 88.3 | ± | 3.4 | abA | 92.4 | ± | 0.9 | aA | |
| Icatu | MD | 79.7 | ± | 2.6 | abB | 80.7 | ± | 1.8 | abB | 77.3 | ± | 2.0 | bB | 73.8 | ± | 2.0 | bAB | 78.2 | ± | 3.0 | bB | 89.1 | ± | 1.0 | aA |
| SD | 69.5 | ± | 3.4 | bC | 63.0 | ± | 2.7 | cC | 71.0 | ± | 1.1 | bB | 72.3 | ± | 0.8 | bB | 64.4 | ± | 3.8 | bcC | 89.0 | ± | 0.9 | aA | |
| WW | 91.2 | ± | 1.1 | aA | 89.0 | ± | 1.6 | aA | 85.2 | ± | 2.2 | aA | 83.5 | ± | 2.3 | aA | 86.3 | ± | 2.6 | aA | 87.3 | ± | 1.5 | aA | |
| Obatã | MD | 86.5 | ± | 1.1 | aAB | 83.8 | ± | 2.4 | aAB | 81.2 | ± | 1.4 | aAB | 82.6 | ± | 2.1 | aA | 79.4 | ± | 1.5 | aAB | 86.7 | ± | 0.7 | aA |
| SD | 82.8 | ± | 2.7 | abB | 74.6 | ± | 4.9 | bB | 74.0 | ± | 2.9 | bB | 79.2 | ± | 3.0 | aA | 77.3 | ± | 1.6 | abB | 85.6 | ± | 1.6 | aA | |
| Predawn ΨW (MPa) | |||||||||||||||||||||||||
| WW | -0.42 | ± | 0.06 | aA | -0.54 | ± | 0.06 | aA | -0.66 | ± | 0.10 | aA | -0.63 | ± | 0.09 | aA | -0.41 | ± | 0.05 | aA | -0.42 | ± | 0.06 | aA | |
| Apoatã | MD | -0.72 | ± | 0.07 | abAB | -0.88 | ± | 0.05 | abA | -1.22 | ± | 0.14 | bAB | -0.84 | ± | 0.09 | abA | -0.83 | ± | 0.28 | abAB | -0.43 | ± | 0.03 | aA |
| SD | -1.02 | ± | 0.24 | abB | -1.51 | ± | 0.21 | bB | -1.61 | ± | 0.31 | bB | -1.06 | ± | 0.03 | abA | -1.32 | ± | 0.45 | bB | -0.47 | ± | 0.04 | aA | |
| WW | -0.40 | ± | 0.04 | aA | -0.56 | ± | 0.07 | aA | -0.85 | ± | 0.12 | aA | -0.49 | ± | 0.12 | aA | -0.37 | ± | 0.04 | aA | -0.37 | ± | 0.03 | aA | |
| Icatu | MD | -1.11 | ± | 0.04 | bB | -1.46 | ± | 0.22 | bcB | -1.99 | ± | 0.10 | cdB | -2.22 | ± | 0.18 | dB | -2.16 | ± | 0.09 | dB | -0.40 | ± | 0.05 | aA |
| SD | -2.86 | ± | 0.07 | bC | -3.13 | ± | 0.39 | bC | -2.96 | ± | 0.28 | bC | -2.95 | ± | 0.27 | bC | -3.24 | ± | 0.36 | bC | -0.42 | ± | 0.03 | aA | |
| WW | -0.46 | ± | 0.05 | aA | -0.56 | ± | 0.06 | aA | -0.81 | ± | 0.09 | aA | -0.55 | ± | 0.04 | aA | -0.37 | ± | 0.04 | aA | -0.45 | ± | 0.06 | aA | |
| Obatã | MD | -0.86 | ± | 0.12 | abAB | -0.98 | ± | 0.21 | abA | -1.83 | ± | 0.14 | cB | -1.31 | ± | 0.15 | bcB | -1.35 | ± | 0.24 | bcB | -0.45 | ± | 0.03 | aA |
| SD | -1.33 | ± | 0.21 | bB | -2.10 | ± | 0.09 | cB | -2.49 | ± | 0.12 | cC | -2.01 | ± | 0.09 | cC | -2.12 | ± | 0.32 | cC | -0.56 | ± | 0.06 | aA | |
For each parameter, the mean values ± SE (n = 5) followed by different letters express significant differences between temperature treatments for the same water availability level (a, b, c), or between water treatments for each temperature treatment (A, B, C), always separately for each genotype.