Elevated CO2 induces age-dependent restoration of growth and metabolism in gibberellin-deficient plants

Main conclusion The effect of elevated [CO 2 ] on the growth of tomato plants with reduced GA content is influenced by developmental stage. The increase of carbon dioxide (CO 2 ) in the atmosphere during the last decades has aroused interest in the function of this gas in the growth and development of plants. Despite the known association between elevated CO 2 concentration ([CO 2 ]) and plant growth, its effects in association with gibberellin (GA), plant hormone that regulates de major aspects of plant growth, are still poorly understood. Therefore, we evaluated the effect of elevated [CO 2 ] on growth and primary metabolism in tomato plants with drastic reduction in GA content ( gib-1 ) at two different growth stages (21 and 35 days after germination, dag). Disruption on growth, photosynthetic parameters and primary metabolism were restored when gib-1 plants were transferred to elevated [CO 2 ] at 21 dag. Elevated [CO 2 ] also stimulated growth and photosynthetic parameters in Wild type (WT) plants at 21 dag, however, minor changes were observed in the level of primary metabolites. At 35 dag, elevated [CO 2 ] did not stimulate growth in WT plants and gib-1 mutants showed their characteristic stunted growth phenotype.