Halophytic plants, unlike most plants, are able to survive in stressful saline environments. Halophytes possess adaptations to osmoregulate, which gives them a competitive edge in saline environments such as coastal salt marshes. Our group analyzed the responses to salinity of the halophytic plant, Limonium californicum, which is present in California’s coastal salt marshes. We hypothesized that the photosynthetic rate of the Limonium californicum plants would decrease with increasing saline water treatments. In order to test this hypothesis, we watered L. californicum plants with solutions of varying salinity over the course of four days. We measured the photosynthetic rates using the LiCor-6400 portable gas exchange system and used a one-way ANOVA statistical test with a Fisher's post-hoc test to analyze our results. We also measured the water potential of the plants with a Scholander-Hammel pressure chamber. We found that the photosynthetic rate of L. californicum decreases significantly as the soil water increases in salinity. However, we also found that the plants still survived and were able to maintain a positive photosynthetic rate even under -4.39 Mega Pascals of pressure. Our results were consistent with our hypothesis and are significant because understanding halophytic plant responses and adaptations to saline environments is important today due to climate change. If we were able to identify more halophyte adaptations to excess salt, in addition to salt glands, this information would help scientists engineer more stress-tolerant crops to withstand the climate changes and effects on water salinity occurring today.
Borges, Adriana J.; Chau, Elizabeth S.; and McKitrick, Justine M., "The Effects of Salinity on the Photosynthetic Rate of Limonium californicum" (2015). Pepperdine University, Featured Research. Paper 208.