Premium
Interaction of elevated CO 2 and O 3 on growth, photosynthesis and respiration of three perennial species grown in low and high nitrogen
Author(s) -
Volin John C.,
Reich Peter B.
Publication year - 1996
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1996.tb00531.x
Subject(s) - photosynthesis , respiration , perennial plant , relative growth rate , stomatal conductance , nitrogen , respiration rate , botany , horticulture , biology , chemistry , growth rate , geometry , mathematics , organic chemistry
Seedlings of three species native to central North America, a C 3 tree, Populus tremuloides Michx., a C 3 grass, Agropyron smithii Rybd., and a C 4 grass, Bouteloua curtipendula Michx., were grown in all eight combinations of two levels each of CO 2 , O 3 and nitrogen (N) for 58 days in a controlled environment. Treatment levels consisted of 360 or 674 μmol mol ‐1 CO 2 , 3 or 92 nmol mol ‐1 O 3 , and 0.5 or 6.0 m M N. In situ photosynthesis and relative growth rate (RGR) and its determinants were obtained at each of three sequential harvests, and leaf dark respiration was measured at the second and third harvests. In all three species, plants grown in high N had significantly greater whole‐plant mass, RGR and photosynthesis than plants grown in low N. Within a N treatment, elevated CO 2 did not significantly enhance any of these parameters nor did it affect leaf respiration. However, plants of all three species grown in elevated CO 2 had lower stomatal conductance compared to ambient CO 2 ‐exposed plants. Seedlings of P. tremuloides (in both N treatments) and B. curtipendula (in high N) had significant ozone‐induced reductions in whole‐plant mass and RGR in ambient but not under elevated CO 2. This negative O 3 impact on RGR in ambient CO 2 was related to increased leaf dark respiration, decreased photosynthesis and/or decreased leaf area ratio, none of which were noted in high O 3 treatments in the elevated CO 2 environment. In contrast, A. smithii was marginally negatively affected by high O 3.