Interactions between increasing CO2 concentration and temperature on plantgrowth

The global environment is changing with increasing temperature and atmosphe ric carbon dioxide concentration, [CO2]. Because these two factors are conc omitant, and the global [CO2] rise will affect all biomes across the full g lobal range of temperatures, it is essential to review the theory and obser vations on effects of temperature and [CO2] interactions on plant carbon ba lance, growth, development, biomass accumulation and yield, Although there are sound theoretical reasons for expecting a larger stimulation of net CO2 assimilation rates by increased [CO2] at higher temperatures, this does no t necessarily mean that the pattern of biomass and yield responses to incre asing [CO2] and temperature is determined by this response. This paper revi ews the interactions between the effects of [CO2] and temperature on plants . There is little unequivocal evidence for large differences in response to [CO2] at different temperatures, as studies are confounded by the differen t responses of species adapted and acclimated to different temperatures, an d the interspecific differences in growth form and development pattern. We conclude by stressing the importance of initiation and expansion of meriste ms and organs and the balance between assimilate supply and sink activity i n determining the growth response to increasing [CO2] and temperature.