Photosynthetic limitations in two Antarctic vascular plants : importance of leaf anatomical traits and Rubisco kinetic parameters

© The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Bibliographische Detailangaben
Veröffentlicht in:Journal of experimental botany. - 1985. - 68(2017), 11 vom: 17. Mai, Seite 2871-2883
1. Verfasser: Sáez, Patricia L (VerfasserIn)
Weitere Verfasser: Bravo, León A, Cavieres, Lohengrin A, Vallejos, Valentina, Sanhueza, Carolina, Font-Carrascosa, Marcel, Gil-Pelegrín, Eustaquio, Javier Peguero-Pina, José, Galmés, Jeroni
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2017
Zugriff auf das übergeordnete Werk:Journal of experimental botany
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Antarctic plants Rubisco leaf traits mesophyll conductance photosynthesis temperature Carbon 7440-44-0 mehr... Ribulose-Bisphosphate Carboxylase EC 4.1.1.39
Beschreibung
Zusammenfassung:© The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Particular physiological traits allow the vascular plants Deschampsia antarctica Desv. and Colobanthus quitensis (Kunth) Bartl. to inhabit Antarctica. The photosynthetic performance of these species was evaluated in situ, focusing on diffusive and biochemical constraints to CO2 assimilation. Leaf gas exchange, Chl a fluorescence, leaf ultrastructure, and Rubisco catalytic properties were examined in plants growing on King George and Lagotellerie islands. In spite of the species- and population-specific effects of the measurement temperature on the main photosynthetic parameters, CO2 assimilation was highly limited by CO2 diffusion. In particular, the mesophyll conductance (gm)-estimated from both gas exchange and leaf chlorophyll fluorescence and modeled from leaf anatomy-was remarkably low, restricting CO2 diffusion and imposing the strongest constraint to CO2 acquisition. Rubisco presented a high specificity for CO2 as determined in vitro, suggesting a tight co-ordination between CO2 diffusion and leaf biochemistry that may be critical ultimately to optimize carbon balance in these species. Interestingly, both anatomical and biochemical traits resembled those described in plants from arid environments, providing a new insight into plant functional acclimation to extreme conditions. Understanding what actually limits photosynthesis in these species is important to anticipate their responses to the ongoing and predicted rapid warming in the Antarctic Peninsula
Beschreibung:Date Completed 29.11.2017
Date Revised 18.03.2024
published: Print
Citation Status MEDLINE
ISSN:1460-2431
DOI:10.1093/jxb/erx148