JXB Advance Access originally published online on March 25, 2009
Journal of Experimental Botany 2009 60(8):2379-2390; doi:10.1093/jxb/erp071
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
This article appears in the following Journal of Experimental Botany issue: Special Issue: Mesophyll conductance to CO2: mechanisms, modelling, and ecological implications [View the issue table of contents]
Responses of gm to Interacting Environmental Factors |
The role of mesophyll conductance during water stress and recovery in tobacco (Nicotiana sylvestris): acclimation or limitation?
Grup de Recerca en Biologia de les Plantes en Condicions Mediterrànies, Departament de Biologia (UIB-IMEDEA), Universitat de les Illes Balears, Carretera de Valldemossa km 7.5, 07122 Palma de Mallorca, Spain
* To whom correspondence should be addressed. E-mail: alexander.galle{at}uib.es
While the responses of photosynthesis to water stress have been widely studied, acclimation to sustained water stress and recovery after re-watering is poorly understood. In particular, the factors limiting photosynthesis under these conditions, and their possible interactions with other environmental conditions, are unknown. To assess these issues, changes of photosynthetic CO2 assimilation (AN) and its underlying limitations were followed during prolonged water stress and subsequent re-watering in tobacco (Nicotiana sylvestris) plants growing under three different climatic conditions: outdoors in summer, outdoors in spring, and indoors in a growth chamber. In particular, the regulation of stomatal conductance (gs), mesophyll conductance to CO2 (gm), leaf photochemistry (chlorophyll fluorescence), and biochemistry (Vc,max) were assessed. Leaf gas exchange and chlorophyll fluorescence data revealed that water stress induced a similar degree of stomatal closure and decreased AN under all three conditions, while Vc,max was unaffected. However, the behaviour of gm differed depending on the climatic conditions. In outdoor plants, gm strongly declined with water stress, but it recovered rapidly (1–2 d) after re-watering in spring while it remained low many days after re-watering in summer. In indoor plants, gm initially declined with water stress, but then recovered to control values during the acclimation period. These differences were reflected in different velocities of recovery of AN after re-watering, being the slowest in outdoor summer plants and the fastest in indoor plants. It is suggested that these differences among the experiments are related to the prevailing climatic conditions, i.e. to the fact that stress factors other than water stress have been superimposed (e.g. excessive light and elevated temperature). In conclusion, besides gs, gm contributes greatly to the limitation of photosynthesis during water stress and during recovery from water stress, but its role is strongly dependent on the impact of additional environmental factors.
Key words: Drought, mesophyll conductance, Nicotiana sylvestris, photosynthetic limitation, recovery, stomatal conductance, water stress
Received 24 November 2008; Revised 17 February 2009 Accepted 19 February 2009
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
J. Flexas, M. Baron, J. Bota, J.-M. Ducruet, A. Galle, J. Galmes, M. Jimenez, A. Pou, M. Ribas-Carbo, C. Sajnani, et al. Photosynthesis limitations during water stress acclimation and recovery in the drought-adapted Vitis hybrid Richter-110 (V. berlandierixV. rupestris) J. Exp. Bot., May 1, 2009; 60(8): 2361 - 2377. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. Niinemets, A. Diaz-Espejo, J. Flexas, J. Galmes, and C. R. Warren Role of mesophyll diffusion conductance in constraining potential photosynthetic productivity in the field J. Exp. Bot., May 1, 2009; 60(8): 2249 - 2270. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Perez-Martin, J. Flexas, M. Ribas-Carbo, J. Bota, M. Tomas, J. M. Infante, and A. Diaz-Espejo Interactive effects of soil water deficit and air vapour pressure deficit on mesophyll conductance to CO2 in Vitis vinifera and Olea europaea J. Exp. Bot., May 1, 2009; 60(8): 2391 - 2405. [Abstract] [Full Text] [PDF] |
||||
