The effects of red, blue, and green light wavelengths on the population growth of thephotoautotrophic ​Chlamydomonas reinhardtii

  • Loretta Huang
  • Adria Lwin
  • Jennifer Cheng
  • Karen Shan Wei Chen


The goal of this experiment is to see the photosynthetic efficiency of Chlamydomonas reinhardtii under different wavelengths of light, in relation to the types of lights they experience in nature. Cultures of C. reinhardtii were put under varying wavelengths including red, blue, green and fluorescent light to determine if the differing wavelengths influence their population growth. The cultures were first diluted, arranged in their specific light conditions with four replicates each, and placed in a temperature-controlled room of 17°C throughout a 15-day period. Cell counts were taken on days 3, 6, 7, 8, 10 and 15. Once all of the data was collected, a one-way ANOVA test was conducted which yielded a p-value of 0.003 indicating the results were statistically significant. Subsequently, a Tukey-Kramer post-hoc analysis was conducted on both data including and excluding the control group due to a skew in data. All experimental conditions were found statistically different than the control group but not from each other, however after removing the control group, the blue condition was statistically different than both the red and the green condition but the red and green were not statistically different from each other.