Climate Change and Plant Water Balance: The Role of Aquaporins – A Review

Abstract

In the context of global change, attention has been focused on the increases in CO 2 and temperature, as well as a reduction in the global solar irra-diance. In this chapter we have explored how components of global change such as CO 2 , temperature and radiation will affect water uptake by plants. We focus on how aquaporins will respond to these environmental factors in order to maintain water balance in plants according to the water demand. Plant growth may be stim-ulated directly by increasing CO 2 concentration, through enhanced photosynthesis, or, indirectly, through induced plant water consumption. However, the fine regu-lation of aquaporins, also involved in CO 2 transport through membranes, will be crucial in the control of H 2 O and CO 2 diffusion. Raised temperatures may ben-efit some crops but disadvantage others through increased evapotranspiration and thermal damage. However, in general, plants can develop different adaptive mecha-nisms in order to avoid water-deficit stress and excess transpiration modulating the hydraulic conductance, which involve the expression and activity of aquaporins. In the same way, the response of plants to the amount of perceived radiation affects water balance. Therefore, the study of aquaporin regulation is necessary for estab-lishing future adaptation of plants to global change.