Back to Search
Start Over
Maximizing leaf carbon gain in varying saline conditions: An optimization model with dynamic mesophyll conductance
- Source :
- The Plant Journal. 101:543-554
- Publication Year :
- 2019
- Publisher :
- Wiley, 2019.
-
Abstract
- While the adverse effects of elevated salinity levels on leaf gas exchange in many crops are not in dispute, representing such effects on leaf photosynthetic rates (A) continues to draw research attention. Here, an optimization model for stomatal conductance (gc ) that maximizes A while accounting for mesophyll conductance (gm ) was used to interpret new leaf gas exchange measurements collected for five irrigation water salinity levels. A function between chloroplastic CO2 concentration (cc ) and intercellular CO2 concentration (ci ) modified by salinity stress to estimate gm was proposed. Results showed that with increased salinity, the estimated gm and maximum photosynthetic capacity were both reduced, whereas the marginal water use efficiency λ increased linearly. Adjustments of gm , λ and photosynthetic capacity were shown to be consistent with a large corpus of drought-stress experiments. The inferred model parameters were then used to evaluate the combined effects of elevated salinity and atmospheric CO2 concentration (ca ) on leaf gas exchange. For a given salinity level, increasing ca increased A linearly, but these increases were accompanied by mild reductions in gc and transpiration. The ca level needed to ameliorate A reductions due to increased salinity is also discussed using the aforementioned model calculations.
- Subjects :
- 0106 biological sciences
0301 basic medicine
Salinity
Stomatal conductance
Agricultural Irrigation
Chloroplasts
medicine.medical_treatment
Plant Science
Biology
Photosynthesis
01 natural sciences
03 medical and health sciences
Animal science
Osmotic Pressure
Stress, Physiological
Genetics
medicine
Water-use efficiency
Saline
Transpiration
Water
food and beverages
Conductance
Cell Biology
Carbon Dioxide
Photosynthetic capacity
Droughts
Plant Leaves
030104 developmental biology
Plant Stomata
Capsicum
Mesophyll Cells
010606 plant biology & botany
Subjects
Details
- ISSN :
- 1365313X and 09607412
- Volume :
- 101
- Database :
- OpenAIRE
- Journal :
- The Plant Journal
- Accession number :
- edsair.doi.dedup.....5fef37afadcfa17190e8a0ac5dddc33a