Photosynthesis, carbohydrate levels and chlorophyll fluorescence-estimated intercellular CO2 in water-stressed Casuarina equisetifolia Forst. & Forst.
Article first published online: 1 MAR 2002
1999 Blackwell Science Ltd
Plant, Cell & Environment
Volume 22, Issue 7, pages 867–873, July 1999
How to Cite
SÁnchez-RodrÍguez, J., PÉrez, P. and MartÍnez-Carrasco, R. (1999), Photosynthesis, carbohydrate levels and chlorophyll fluorescence-estimated intercellular CO2 in water-stressed Casuarina equisetifolia Forst. & Forst. Plant, Cell & Environment, 22: 867–873. doi: 10.1046/j.1365-3040.1999.00447.x
- Issue published online: 1 MAR 2002
- Article first published online: 1 MAR 2002
- carbon metabolism;
- chlorophyll fluorescence;
- stomatal conductance;
- water stress
The effect of long-term water stress on photosynthetic carbon metabolism in Casuarina equisetifolia Forst. & Forst. was analysed by measuring CO2 assimilation, stomatal conductance, the quantum yield of photosystem II (ΦPSII), enzyme activities, and the levels of photosynthetic intermediates and carbohydrates. CO2 assimilation decreased under water stress while the intercellular CO2 concentration (Ci) as estimated by gas exchange measurements remained high. However, the estimates of Ci from measurements of ΦPSII suggest that the decrease in photosynthesis can be explained in terms of stomatal closure. Water stress decreased total stromal fructose-1,6-bisphosphatase activity and did not alter the activities and activation states of ribulose bisphosphate carboxylase oxygenase and NADP-dependent malate dehydrogenase (NADP-MDH). The concentration of photosynthetic metabolites, glucose, fructose and sucrose decreased, whereas starch concentrations increased under drought conditions.