2.4.2. *Arabidopsis* Growth Condition

Four days after germination, *Arabidopsis thaliana* ecotype Col-0 seeds and seven mutant lines [21] including *at1g74880*, *at5g54270*, *at3g63190*, *at4g11960*, *at4g22890*, *at2g27680*, and *at4g34830* were sowed and transferred to 48-well plates, containing Murashige and Skoog (MS) agar media for normal conditions, MS agar media supplemented with 75 mM mannitol for mild drought stress, or MS agar media supplemented with 150 mM mannitol for severe drought stress. The plants were then grown in a growth chamber at 22 °C/20 °C, 16/8 h light/dark cycle, 120 μmol photons of PAR <sup>m</sup><sup>−</sup>2·s<sup>−</sup>1, and 60% humidity. RGB imaging was used to collect the green area of plants twice a day via a PlantScreenTM XYZ system (Photon Systems Instruments, Drásov, Czech Republic) [22].
