Mesophyll conductance does not contribute to greater photosynthetic rate per unit nitrogen in temperate compared with tropical evergreen wet-forest tree leaves

© 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 218(2018), 2 vom: 22. Apr., Seite 492-505
1. Verfasser: Bahar, Nur H A (VerfasserIn)
Weitere Verfasser: Hayes, Lucy, Scafaro, Andrew P, Atkin, Owen K, Evans, John R
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2018
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't CO2 drawdown carboxylation capacity mesophyll conductance photosynthetic limitation temperate tropical Carbon Dioxide 142M471B3J mehr... Ribulose-Bisphosphate Carboxylase EC 4.1.1.39 Nitrogen N762921K75
Beschreibung
Zusammenfassung:© 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.
Globally, trees originating from high-rainfall tropical regions typically exhibit lower rates of light-saturated net CO2 assimilation (A) compared with those from high-rainfall temperate environments, when measured at a common temperature. One factor that has been suggested to contribute towards lower rates of A is lower mesophyll conductance. Using a combination of leaf gas exchange and carbon isotope discrimination measurements, we estimated mesophyll conductance (gm ) of several Australian tropical and temperate wet-forest trees, grown in a common environment. Maximum Rubisco carboxylation capacity, Vcmax , was obtained from CO2 response curves. gm and the drawdown of CO2 across the mesophyll were both relatively constant. Vcmax estimated on the basis of intercellular CO2 partial pressure, Ci , was equivalent to that estimated using chloroplastic CO2 partial pressure, Cc , using 'apparent' and 'true' Rubisco Michaelis-Menten constants, respectively Having ruled out gm as a possible factor in distorting variations in A between these tropical and temperate trees, attention now needs to be focused on obtaining more detailed information about Rubisco in these species
Beschreibung:Date Completed 19.09.2019
Date Revised 30.09.2020
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.15031