Leaf anatomical properties in relation to differences in mesophyll conductance to CO(2) and photosynthesis in two related Mediterranean Abies species.
Plant Cell Environ
; 35(12): 2121-9, 2012 Dec.
Article
em En
| MEDLINE
| ID: mdl-22594917
ABSTRACT
Abies alba and Abies pinsapo are closely related species with the same ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco) large subunit (rbcL) but contrasting hydraulic traits and mesophyll structure occurring in the Iberian Peninsula under contrasting conditions. As photosynthesis and hydraulic capacities often co-scale, we hypothesize that these species differ in mesophyll conductance to CO(2) (g(m) ). g(m) and key anatomical traits were measured in both species. Drought-adapted population of A. pinsapo has higher photosynthesis than the more mesic population of A. alba, in agreement with its higher hydraulic capacity. However, A. alba exhibits the largest stomatal conductance (g(s) ), and so water use efficiency (WUE) is much higher in A. pinsapo. The differences in photosynthesis were explained by differences in g(m) , indicating a correlation between hydraulic capacity and g(m) . We report a case where g(m) is the main factor limiting photosynthesis in one species (A. alba) when compared with the other one (A. pinsapo). The results also highlight the discrepancy between g(m) estimates based on anatomical measurements and those based on gas exchange methods, probably due to the very large resistance exerted by cell walls and the stroma in both species. Thus, the cell wall and chloroplast properties in relation to CO(2) diffusion constitute a near-future research priority.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fotossíntese
/
Dióxido de Carbono
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Folhas de Planta
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Abies
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Células do Mesofilo
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article