The alarming and unprecedented rise in the atmo-
spheric concentration of greenhouse gases under global
climate change warrants an urgent need to understand
the synergistic and holistic mechanisms associated with
plant growth and productivity. Photosynthesis is a
major process of sequestration and turnover of the
total carbon on the planet. The extensive literature on
the impacts of climate change demonstrates both posi-
tive and negative effects of rising CO2 on photosynthe-
sis in different groups of higher plants. Significant
variation exists in the physiological, biochemical and
molecular responsiveness to elevated CO2 atmosphere,
among terrestrial plant species including those with
C3, C4 and crassulacean acid metabolic (CAM) path-
ways. However, the regulatory events associated with
the inter- and intraspecific metabolic plasticity gov-
erned by genetic organization in different plants are
little understood. The adaptive acclimation responses
of plants to changing climate remain contradictory.
This review focuses primarily on the impacts of global
climate change on plant growth and productivity with
special reference to adaptive photosynthetic acclima-
tive responses to elevated CO2 concentration. The
effects of elevated CO2 concentration on plant growth
and development, source–sink balance as well as its
interactive mechanisms with other environmental
factors including water availability, temperature and
mineral nutrition are discussed.