Effect of <i>Cer10</i> mutation and light intensity on <i>Arabidopsis thaliana</i> water-uptake rates


  • Evie Au
  • Helon Law
  • Hillary Oxley
  • Kathy Tran


The Arabidopsis thaliana wild-type plant produces cuticular wax on its exterior surface to serve many functions, including the regulation of water loss. Presence of the cer10 mutation results in a decreased amount of cuticular wax production. In order to determine both the individual and interdependent effects of the cer10 mutation and light intensity on the water-uptake rate of A. thaliana, we conducted water-uptake experiments on four treatments of A. thaliana plants with six replicates each: wild-type light, mutant light, wild-type dark, and mutant dark. Plants were kept in a 20oC incubator for 72 hours prior to the experiment in their respective light conditions. Water-uptake rate was calculated using the time required for A. thaliana to uptake the methylene blue indicator to its bottom-most leaves, the uptake distance. The mean water uptake rates for wild-type light, mutant light, wild-type dark, and mutant dark plants were found to be 42 µm/s, 30 µm/s, 26 µm/s, and 62 µm/s, respectively. No statistically significant differences were observed between light and dark treatments or wild-type and mutant plants; however, the differing effect of light and dark treatments on wild-type and mutant plants was significant (p-value = 0.026). The latter result was not as predicted, in that increased light intensity led to decreased, instead of increased, water-uptake rates of mutant plants, and increased water-uptake rates of wild-type plants. This may have been due to unaccounted-for physiological factors.