Relation of Stomatal Movement and Ion Content Change of Guard Cells in Populus berolinensis under Water Stress

Cuttings of Populus berolinensis were treated by water stress.The changes of stomatal aperture were observed by scanning electron microscope (SEM).Ion contents in guard cells were analysed by SEM X ray microanalysis.The results indicated that stomata almost closed by strong water stress.When stomatal closure, K+ content decreased and Ca2+ content increased obviously in guard cells.It suggests that K+ and Ca2+ might regulate the stomatal movement.The flux of K+ and Ca2+ might play an important role in stomatal opening and closing.