Preliminary Studies On Physiology And Biochemistry Of Different Peony Cultivars In Vase

Based on the integrated study of various physiological processes of the cut Peony flowers('Fen Yunu', 'Hongpan Jinzhu', 'Fengyu Luojinchi', 'Zi Fengyu', 'Lian Tai', Hu guang Shanse', 'Qiao Ling', 'Hong Xiuqiu', 'Wei Dingzi', 'Da Fugui', 'Yanzi Xiangyang') in vase, including the water metabolism, membrane permeability and macromolecular matter, antioxidant enzymes and the level of membrane lipid peroxidation. The main factors that influence the vase life and visual value of cut Peony flower are tested. The aims are to find some factors that are helpful to peony cut flower cultivars selecting and explore the senescence reasons. The results show that:â‘  The diameter of flower stem is related to diameter of the flower and the vase life. Quality Index (as flower stem intension) can evaluate the cut flowers quality.â‘¡ Water deficiency stress caused by the water loss during vase holding is one of the reasons for quality descent of cut flower. Vase life is related to the balance of water uptake and water loss, but vase life has no relations with water uptake and water loss in vase, it is negative to the water uptake and water loss of the flowers at 1st day. To improve the abilities of water uptake of cut peony flowers, keep the water balance of water uptake and water loss can prolong the vase life. Water uptake and loss of the flowers at 1st day can be used as a standard for peony cut flower cultivars selecting.â‘¢Membrane penetration increases in vase. The cultivars membrane penetration increasing rapidly have shorter vase life than those increasing smoothly at the early stage of vase holding. The membrane lipid peroxidation induces the membrane permeability, but it is not the only reason. Other systems may play roles. And the membrane stability of leaves is better than the petals. The marked increase of membrane penetration is related to the balance of water-uptake.â‘£ Vase life has relations to the amount of soluble protein but not to the amount of free sucrose in peony cut flowers. Soluble protein of the cultivars showed fluctuation at early stage has longer vase life than that their soluble protein increased or decreased constantly. Soluble protein and free sucrose decrease before the senescence of cut flowers,physiological changes are earlier than exterior forms.⑤The SOD activity of leaves is lower than that of petals during the vase holding. Active oxygen (O₂^-) accumulates more than petals, resulting in membrane lipid peroxidation, which promots the production MDA and the membrane permeability of peony cut flowers. Leaves senescence is earlier than the petals.