The differential responses of Aegiceras corniculatum and Kandelia candel under salt stress and re-watering phase. A study of leaf electrophysiological and growth parameters

Abstract

This study investigates differential responses of Aegiceras corniculatum and Kandelia candel mangrove species, using physiological capacitance (CP), photosynthetic, and growth parameters under different salt stress and re-watering conditions. Experiment was conducted at various NaCl levels. The Results indicated that CP was significantly affected in stress phase due to the limitation of salt storage capacity of the vacuole. Although A. corniculatum has a secreting effect, the solute concentration in vacuole was significantly higher than K. candel at M and H treatment, because their volume of vacuole was lower than K. candel species. In the re-watering phase, CP values of both species increased at M-L and H-M treatments respectively. Furthermore, CP was positively correlated with net photosynthesis and stomatal conductance. This finding suggests that the concentration of solute in vacuole is an important factor controlling photosynthesis and growth parameters, and CP can better represent salt concentration in the plant leaf.

Keywords

• mangroves
• physiological capacitance
• photosynthetic parameters
• salt stress
• re-watering phase