Effects of soil moisture on growth and photosynthesis of Euonymus japonicus

A pot experiment was conducted to determine the effect of 4 soil moisture gradients (HS, heavydrought stress; MS, middledrought stress; LS, lightdrought stress; CK, control) on increment, leaf shape and dropping, and photosynthesis of Euonymus japonicus. The results of this study showed that MS and HS significantly reduced the increment (P＜0.01), and significantly encouraged the leaves to drop (P＜0.01) , implying that MS and HS decreased the ornamental quality of E.japonicus. MS and HS also enabled the leaf area to become smaller and changed the leaves from long strip shape to ovate shape as in order: HSMSLSCK (P0.01). The response of photosynthetic rate, transpiration rate, water use efficiency, and light energy efficiency of E.japonicus to soil drought stress showed a similar trendy, indicating that drought stress significantly affect these index. This study suggested that reducing irrigation in the garden greening management is an effectively way to controlling E.japonicus growth and exerting its ornamental quality, which would benefit water saving and pruning.