Seedling and root growth of the ubc7/13/14 mutant seedlings under several stress conditions. The wild-type (WT) and ubc7/13/14 mutant seeds were sterilized, stored at 4 °C, and then plated onto the normal or treatment plates with the addition of a stress-causing reagent. In each plate, seven WT and seven mutant seeds were planted side by side. The images were taken after 14 days of incubation in a plant tissue culture chamber. (A) Normal plate (1/2 MS + 1% sucrose + 0.7% agar), (B) 120 mM NaCl, (C) 3% mannitol, (D) 0.15 μM PBI425 (an abscisic acid (ABA) analog), and (E) 0.03 μM paraquat.