Abstract: 【Objective】To investigate the effects of various anthocyanidin components on tree peony flower hues.【Methods】Six different varieties of tree peony were selected as experimental materials.The color system of tree peonies was classified according to visualization,color chart and colorimeter values.The chlorophyll,carotenoid,cyanidin,anthocyanin,and flavonoid content were determined among the petals,and the cyanidin and anthocyanin components were detected by mass spectrometer.【Results】The six varieties of tree peony could be divided into five major colors：composite color,yellow,green,purplish red,and red. The petals of cyanidin and anthocyanin varied significantly among tree peony varieties. The red system Nihonghuancai exhibited the highest concentration,while the green system Lvmuyinyu showed the lowest. Pelargonidin and paeoniflor were not detected in the composite color system Lanyueliang,nor was peonidin in the green system Lvmuyinyu. Moreovre,the contents of cyanidin,pelargonidin,and peonidin in the red system Nihonghuancai,as well as petunidin,delphinidin,and malvidin in the purplish red system Luoyanghong,were higher than those in other color system. Pelargonidin-3-O-glucoside content in red system was highest,656.17 times higher than that in yellow system and 102.96 times higher than in purplish red system. The content of paeoniflorin 3-O-glucoside was higher in the red system and purplish red system,which was 59 064.28,34 283.83 ng/g,respectively.【Conclusion】The cyanidin is more important for the coloring of red system and purplish red system than other color systems. Pelargonidin-3-O-glucoside is an important pigment factor that causes the difference in purple and red peonies,and peonidin 3-O-glucoside is one of the main coloration factors for red system and purplish red system.

Key words: Tree peony, Flower color, Coloration factor, Cyanidin, Anthocyanin