moisture levels through adjusting the size of stomatal
opening according to their physiological and structural
properties (Nobel 2005).
The closing and opening of the guard cells of stomata
involve changing osmotic pressure and ion fluxes between
epidermal cells and guard cells (Buckley 2005).This requires
production of oxidizing species in the guard cells (Wang &
Song 2008) and activation and deactivation of ion channels
and transporters in the guard cell plasma membrane
(Pandey, Zhang & Assmann 2007).