Dynamic changes of canopy-scale mesophyll conductance to CO(2) diffusion of sunflower as affected by CO(2) concentration and abscisic acid

0367247 - BC 2012 RIV GB eng J - Journal Article
Schaufele, R. - Šantrůček, Jiří - Schnyder, H.
Dynamic changes of canopy-scale mesophyll conductance to CO(2) diffusion of sunflower as affected by CO(2) concentration and abscisic acid.
Plant Cell and Environment. Roč. 34, č. 1 (2011), s. 127-136. ISSN 0140-7791. E-ISSN 1365-3040
R&D Projects: GA ČR GA206/08/0787
Institutional research plan: CEZ:AV0Z50510513
Keywords : carbon isotope discrimination * water-stress * in-vivo
Subject RIV: EF - Botanics
Impact factor: 5.215, year: 2011

Leaf-level measurements have shown that mesophyll conductance (g(m)) can vary rapidly in response to CO(2) and other environmental factors, but similar studies at the canopy-scale are missing. Here, we report the effect of short-term variation of CO(2) concentration on canopy-scale g(m) and other CO(2) exchange parameters of sunflower (Helianthus annuus L.) stands in the presence and absence of abscisic acid (ABA) in their nutrient solution. g(m) was estimated from gas exchange and on-line carbon isotope discrimination (Delta(obs)) in a 13CO(2)/12CO(2) gas exchange mesocosm. The isotopic contribution of (photo)respiration to stand-scale Delta(obs) was determined with the experimental approach of Tcherkez et al. Without ABA, short-term exposures to different CO(2) concentrations (C(a) 100 to 900 mu mol mol-1) had little effect on canopy-scale g(m).
Permanent Link: http://hdl.handle.net/11104/0201991