The stomatal morphological characters,distribution,diurnal course,and nonuniform stomatal closure were studied by using a combination of scanning electron micrography and gas exchange after fixing leaf samples in liquid nitrogen.The results show that the morphological characters of triploid clone ZH4 are larger than that of diploid clone BL1,but the density of the two clones is reverse.Clone ZH4 is more sensitive to the change of environmental factors than clone BL1.The authors suggest a formula for modi...