| Autor: |
Hafiz Maherali, H. W. Polley, C. D. Reid, Robert B. Jackson, Hyrum B. Johnson |
| Rok vydání: |
2002 |
| Předmět: |
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| Zdroj: |
Plant, Cell & Environment. 25:557-566 |
| ISSN: |
0140-7791 |
| DOI: |
10.1046/j.1365-3040.2002.00832.x |
| Popis: |
An investigation to determine whether stomatal acclimation to [CO 2 ] occurred in C 3 /C 4 grassland plants grown across a range of [CO 2 ] (200‐550 µ mol mol − − − 1 ) in the field was carried out. Acclimation was assessed by measuring the response of stomatal conductance ( g s ) to a range of intercellular CO 2 (a g s ‐ C i curve) at each growth [CO 2 ] in the third and fourth growing seasons of the treatment. The g s ‐ C i response curves for Solanum dimidiatum (C 3 perennial forb) differed significantly across [CO 2 ] treatments, suggesting that stomatal acclimation had occurred. Evidence of non‐linear stomatal acclimation to [CO 2 ] in this species was also found as maximum g s ( g smax ; g s measured at the lowest C i ) increased with decreasing growth [CO 2 ] only below 400 µ mol mol − 1 . The substantial increase in g s at subambient [CO 2 ] for S. dimidiatum was weakly correlated with the maximum velocity of carboxylation ( V cmax ; r 2 = 0·27) and was not associated with CO 2 saturated photosynthesis ( A max ). The response of g s to C i did not vary with growth [CO 2 ] in Bromus japonicus (C 3 annual grass) or Bothriochloa ischaemum (C 4 perennial grass), suggesting that stomatal acclimation had not occurred in these species. Stomatal density, which increased with rising [CO 2 ] in both C 3 species, was not correlated with g s . Larger stomatal size at subambient [CO 2 ], however, may be associated with stomatal acclimation in S. dimidiatum . Incorporating stomatal acclimation into modelling studies could improve the ability to predict changes in ecosystem water fluxes and water availability with rising CO 2 and to understand their magnitudes relative to the past. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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