Studies On The Physiological And Biochemistry Of Cut-flower Eustoma Grandiflorm During Senescence Process

Abstract:Eustoma grandiflorm, belonging to Eustoma ressellianum, gentianaceae, hasbecome a promising flower in the cut-flower market due to its elegant color andbeautiful appearance. However, such problems as abnormal flowering, prematurepetal wilting, branch break, scape bending, haulm yellowing or withering often occurin the post-harvest transport and during the vase-holding process, seriously affectingthe ornamental value. We focused on the physiological changes, including watercontent, soluble sugar content, soluble protein content, activity of POD and activity ofSOD during the vase-holding process after the Eustoma grandiflorm var. of PlatinaViolet, King Pink and Rose Green were treated by using ETP and 1-MCP. Also, thechanging of petal protein was further studied by means of SDS-PAGE electrophoretictechnique with a view of deeply studying the senescence of cut-Eustoma at molecularlevel and provide some theoretical reference for Genetic Breeding. Meantime, takingthe King Pink as experimental material, the senescence process of cut-Eustoma is alsostudied in the context of cytology.The result as follows:1．ETP concentration(24h), respectively 25mg/L,50mg/L,100mg/L,200mg/L,400 mg/ L, and 1-MCP concentration, respectively 500mg/L (8h,10h),800mg/L (8h,10h), were used for treating flower branch of Platina Violet petal. The result showedthat 200mg/L ETP for 24h is capable of distinctly inhibiting the normal developmentof Platina Violet petal, shortening the petal life, and reducing its ornamental quality.800mg/L1-MCP for 8h more ideally enables Platina Violet petal to postpone senility,extend the vase life, and improve the ornamental value.2．By SDS-PAGE gel. electrophoresis technique and computer-aided image analysis,three varieties of Platina Violet, King Pink and Rose Green were taken asexperimental material, and then treated by using distilled water, 800mg/L 1-MCP for8h and 200mg/L ETP for 24h. By doing so, three types of protein maps were obtained.The result showed that in contrast with the control, 1-MCP lanes were more andthicker than water lanes; ETP lanes were fewer and thinner than water lanes. As aresult, there were four change trends: some lanes was relatively steady, some lanesdisappeared, some lanes flashed and some lanes stayed for a long time after composed3．Though Platina Violet, King Pink and Rose Green had different reactivity after treatments of ETP,water and 1-MCP, they had similar change trend in sametreatment.4．The ultra-structure during bud, blooming and wilting period of Platina Violet petalwere observed by means of TEM (transmission electron microscopy). The resultshowed that the senescence of cut-Eustoma petal was a typically programmed celldeath, for example, karyon and nucleolus and cytoplasm concentrating, chromatinedging, cell and organelle cavuming, languish-ball appearing etc. Further, it wascharacterized as the induced programmed cell death under adverse circumstance,including plasmolysis, vacuole dying out too early. In addition, lots of fecula and fatballs were found during blooming period, but not during bud and wilting periods.Therefore, it can be concluded that Eustoma petal accumulated the main energymaterial for future metabolism during the booming period. This may be one of the keyreasons that cut-Eustoma has a longer vase life.