Fig. 2

Physiological Parameters in Response to Treatments Applied. A Expression levels of CAROTENOID CLEAVAGE DIOXYGENASE1 (HvNCED1), HvA22, and β-GLUCOSIDASE8 (HvBG8) in response to ABA treatment at T1. Stars indicate statistically significant differences between groups: *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001. B Stomatal conductance measured at T1, with significant differences between variants marked by stars as indicated above. Physiological parameters measured at T2 and T3: (C) Stomatal conductance at T2 and T3, (D) Chlorophyll content at T2 and T3, (E) Schematic representation of chlorophyll a fluorescence parameter measured and their role in the photosynthesis process. (F-I) Photosynthetic efficiency parameters: (F) Active PSII reaction centers per cross-section (RC/CS), (G) Absorption flux per cross-section (ABS/CS), (H) Trapping flux per cross-section (TR0/CS), and (I) Electron-transport flux per cross-section (ET0/CS). One-way ANOVA (P ≤ 0.05) followed by Tukey HSD test (P ≤ 0.05) was applied to identify significant differences between experimental variants. Statistically significant differences (P ≤ 0.05) are denoted by different letters, (J) Representative images of barley plants under control, control + ABA, drought + ABA, and drought conditions at T2