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Interactive Effects of CO2, Salinity and Water Level on the Growth of a Coastal Halophyte

Paper Reviewed
Pérez-Romero, J.A., Duarte, B., Barcia-Piedras, J.-M., Matos, A.R., Redondo-Gómez, S., Cacador, I. and Mateos-Naranjo, E. 2019. Investigating the physiological mechanisms underlying Salicornia ramosissima response to atmospheric CO2 enrichment under coexistence of prolonged soil flooding and saline excess. Plant Physiology and Biochemistry 135: 149-159.

Common glasswort (Salicornia ramosissima) is a C3 halophyte that inhabits coastal salt marshes and inland saline soils, with the capacity to tolerate a wide range of salinity conditions. However, it is unknown how this species will respond to future climate conditions, which could include increased salinization and waterlogging in coastal areas from increased rates of sea level rise.

Hoping to explore this potential scenario, Pérez-Romero et al. (2019) conducted a full-factorial experiment to investigate the effects of atmospheric CO2 (400 and 700 ppm), water level (water logging and no water logging) and salinity concentration (171 and 510 mM NaCl) on the growth of S. ramosissima. The experiment was conducted under controlled laboratory conditions, where 3 month-old seedlings were subjected to combinations of the various treatment parameters for 45 days. At the end of the experiment, multiple physiological and biochemical parameters were measured to determine the singular and interactive effects of atmospheric CO2, water level and salinity concentration on S. ramosissima growth.

In the words of the authors, the results of their analysis revealed that "elevated atmospheric CO2 concentration improved plant physiological performance under suboptimal root-flooding and saline conditions." This ameliorative effect was mainly due to an upregulation in the plant's energy sink capacity that improved "modulation of the antioxidant enzyme machinery and of the betain accumulation on tissues to cope with oxidative stress, as well as to a great presence in saturated fatty acids." Consequently, Pérez-Romero et al. conclude that "these responses indicate that atmospheric CO2 enrichment would contribute to preserve the development of Salicornia ramosissima against the ongoing process of soil stressful conditions linked with climate change."

Posted 16 April 2019