Table 4.
Chlorophyll a (Chl a), chlorophyll b (Chl b), and total carotenoids (Cx+c) content in leaf tissues of sweet potato pretreated with PBZ subsequently subjected to WW (47.5% SWC), mild water deficit (32.3% SWC; 7 days water withholding) or SWD (17.5% SWC; 14 days water withholding).
| Treatment | Water deficit | 7 days | 14 days | ||||
|---|---|---|---|---|---|---|---|
| Chl a (µg g-1 FW) | Chl b (µg g-1 FW) | Cx+c (µg g-1 FW) | Chl a (µg g-1 FW) | Chl b (µg g-1 FW) | Cx+c (µg g-1 FW) | ||
| cv. ‘Japanese Yellow’ (+) | |||||||
| WW | 85.26ab | 54.82a | 7.25bc | 88.94ab | 53.66ab | 8.03b | |
| WD | 81.99b (3.84%) | 52.80ab (3.65%) | 6.83c (5.79%) | 84.27ab (5.25%) | 52.44ab (2.27%) | 6.88c (14.32%) | |
| cv. ‘Tainung 57’ (-) | |||||||
| 0 μM PBZ | WW | 84.94ab | 56.63a | 8.50a | 96.28a | 55.29a | 9.99ab |
| WD | 80.19b (5.59%) | 51.93b (8.30%) | 6.17c (27.41%) | 82.83b (13.97%) | 51.62b (6.64%) | 6.53c (34.63%) | |
| 17 μM PBZ | WW | 89.47a | 58.16a | 6.94c | 92.91a | 53.55ab | 9.12ab |
| WD | 86.80ab (2.98%) | 53.31ab (8.34%) | 5.65d (18.59%) | 81.16b (12.65%) | 51.61b (3.62%) | 6.06c (33.55%) | |
| 34 μM PBZ | WW | 89.77a | 56.21a | 8.27ab | 98.89a | 56.09a | 10.16a |
| WD | 81.49b (9.23%) | 53.22ab (5.32%) | 7.61bc (7.98%) | 85.54ab (11.71%) | 54.51ab (2.82%) | 7.60bc (25.20%) | |
| 51 μM PBZ | WW | 93.12a | 53.78ab | 8.12ab | 95.69a | 53.43ab | 10.31a |
| WD | 85.76ab (7.90%) | 51.30b (4.61%) | 7.35bc (9.48%) | 86.51ab (9.59%) | 50.83b (4.90%) | 7.20bc (30.17%) | |
Different letters in each column show significant difference at p ≤ 0.01 by Tukey’s HSD. Figures in parentheses represent pigment degradation percentage of water-deficit stressed plants compare to WW in each cultivar.