The Effect of Shading Treatment on Leaf Shape,Leaf Color of Two Kinds of Colored Leaf Shrubs

Two species of colored-leaf shrub Ligustrum×vicaryi and Lorpetalum chindense var.rubrum were used to investigate shading effect on leaf shape,leaf color and pigment.The results showed that both species leaf area reduced gradually and leaf shape changed from strip to oval with the increase of shading intensity.Leaf color of Ligustrum×vicaryi changed from bright golden yellow to dark green,and Lorpetalum chindense var.rubrum from dark brown to red-brown.The shading intensity and shading time significantly affected leaf color.Mass fraction of chlorophyll a and chlorophyll b increased and demonstrated a positive correlation with shading intensity in both species.Carotenoid fructuation showed different trends in two species,Ligustrum×vicaryi decreased and Lorpetalum chindense var.rubrum increased gradually with the enhancement of shading intensity.Shading time showed no obvious effect on pigment content of Ligustrum×vicaryi.Chlorophyll and carotenoid of Lorpetalum chindense var.rubrum decreased with the elongation of shading time.PAL activity reduced with the enhancement of shading intensity.There was difference in soluble sugar content between two shrubs.Soluble sugar content of Ligustrum×vicaryi rose slowly after 30-day shading treatment,and then went down after 60-day shade.