Influence of leaf dry mass per area, CO2, and irradiance on mesophyll conductance in sclerophylls
Leaf photosynthesis (A) is limited by mesophyll conductance (g(m)), which is influenced by both leaf structure and the environment. Previous studies have indicated that the upper bound for g(m) declines as leaf dry mass per area (LMA, an indicator of leaf structure) increases, extrapolating to zero...
| Publié dans: | Journal of experimental botany. - 1985. - 60(2009), 8 vom: 01., Seite 2303-14 |
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| Auteur principal: | |
| Autres auteurs: | , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2009
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| Accès à la collection: | Journal of experimental botany |
| Sujets: | Journal Article Research Support, Non-U.S. Gov't Chlorophyll 1406-65-1 Carbon Dioxide 142M471B3J Chlorophyll A YF5Q9EJC8Y |
| Résumé: | Leaf photosynthesis (A) is limited by mesophyll conductance (g(m)), which is influenced by both leaf structure and the environment. Previous studies have indicated that the upper bound for g(m) declines as leaf dry mass per area (LMA, an indicator of leaf structure) increases, extrapolating to zero at a LMA of about 240 g m(-2). No data exist on g(m) and its response to the environment for species with LMA values higher than 220 g m(-2). In this study, laboratory measurements of leaf gas exchange and in vivo chlorophyll a fluorescence were used concurrently to derive estimates of g(m) in seven species of the Australian sclerophyllous genus Banksia covering a wide range of LMA (130-480 g m(-2)). Irradiance and CO(2) were varied during those measurements to gauge the extent of environmental effects on g(m). A significant decrease of g(m) with increasing LMA was found. g(m) declined by 35-60% in response to increasing atmospheric CO(2) concentrations at high irradiance, with a more variable response (0-60%) observed at low irradiance, where g(m) was, on average, 22% lower than at high irradiance at ambient CO(2) concentrations. Despite considerable variation in A and LMA between the Banksia species, the CO(2) concentrations in the intercellular air spaces (C(i), 262+/-5 micromol mol(-1)) and in the chloroplasts (C(c), 127+/-4 micromol mol(-1)) were remarkably stable |
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| Description: | Date Completed 13.07.2009 Date Revised 01.12.2018 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1460-2431 |
| DOI: | 10.1093/jxb/erp021 |