Effects of Drought Stress on Pigment and Photosynthetic Characteristics in Leaves of Loropetalum chinense var.rubrum

A water-controlling pot experiment was conducted to evaluate the effect of slight,moderate and severe drought stress on pigment and photosynthetic characteristics in leaves of two-year-old seedlings of Loropetalum chinense var.rubrum.The results showed that the amount of Chla, Chlb, Chl and C_x+c all increased generally,while the Chla/Chlb ratio decreased with the aggravation of drought stress.The anthocyanin content decreased in CK,T2 and T3 under continuous drought,which turned leaves green.Drought stress reduced the P_n,T_r,G_s and enhanced the C_i and WUE in Loropetalum chinense significantly,and there were significant correlations among these photosynthetic indices.In summary,Loropetalum chinense tended to be a kind of xerophile plant,which could bear slight drought stress by increasing the chloroplast pigment contents and leaf water use efficiency.In practice,inappropriate water supply should be avoided,otherwise the ornamental value would be affected for the degradation of anthocyanin.