Effect Of Exogenous Glucose On The Synthesis Of Anthocyanin Biosythesis In Tree Peony ’Luoyang Hong’ And ’Taiyang’ Cut Flower

Flower color is one of the important ornamental attributes of tree peony cut flowers,and the composition and content of anthocyanin is one of the main reasons that determine the different colors of cut flower petals.Carbohydrates not only provide respiratory substrates for cut flowers and maintain osmotic pressure,but also regulate the synthesis of anthocyanin in petals in the form of sugar signals in plants.Tree peony flowers are beautiful in color and have very important ornamental value and market value as cut flowers.Therefore,it is revealed that glucose plays a very important role in improving the color of tree peony flowers and the accumulation of anthocyanins after harvest.It is also a technology for color preservation and freshness preservation of tree peony cut flowers.And the molecular cultivation technology of tree peony flowers is of great significance.In this study,tree peony’Luoyanghong’ and’Taiyang’ were used as research materials to explore the causes of fading of tree peony cut flowers.On the basis of comparing the flower color,soluble sugar content,anthocyanin content and related gene expression of on-tree flowers and cut flowers.Above,further study the effects of exogenous glucose,glucose analogues and hexokinase inhibitor treatments on flower morphology,flower color,anthocyanin content and related gene expression.The main findings are as follows:After the cut flowers of tree peony ’Luoyang hong’ and ’Tianyang’ were separated from the mother body,the obvious fading occurred,and the flower color quality decreased significantly.The phenotypic measurement of the tree peony flower color showed that the flower color brightness and redness increased significantly compared with the cut flowers in vivo process.The soluble sugar content in the petals of cut flowers of tree peony’Luoyang hong’ and’Taiyang’ is significantly lower than that of in on-tree flowers.During the blooming period,the accumulation of soluble sugar in the petals of cut flowers is 1/2 of that of on-tree flowers,which is significantly lower than that of on-tree flowers.By HPLC analysis,six anthocyanin glycosides were detected from the petals of tree peony ’Luoyang hong’ and’Taiyang’: Cy3 G,Cy3G5G,Pn3 G,Pn3G5G,Pg3 G and Pg3G5 G.The determination of the content of 6 kinds of anthocyanin found that the contents of Cy3 G,Cy3G5G,Pn3 G and Pn3G5 G in the petals of tree peony’Luoyang hong’ cut flower were significantly lower than those in the on-tree flower.The content of Pn3 G,Pg3G,and Pg3G5 G in the petals of tree peony’Taiyang’ flowers was significantly lower than that of in on-tree flower,but the content of Pn3G5 G in cut flowers was consistent with that in on-tree flowers.The accumulation of total anthocyanin content in-vase flowers of tree peony’Luoyang hong’and’Tianyang’ is 1/2 of that of on-tree flowers during the blooming period,which is significantly lower than the accumulation of on-tree flowers.The expression levels of most regulatory genes and structural genes in cut flowers of tree peony’Luoyanghong’ and’Tianyang’ were significantly lower than those of in on-tree flowers.In cut flowers,Psb HLH1,Psb HLH3,Ps WD40-1,Ps WD40-2,Ps F3’H1,Ps5GT1 and Ps OMT1 gene down-regulation expression may be the main reason for the serious color fading of the cut flowers of peony’Luoyang hong’ and’Tianyang’ and the obvious quality of cut flowers in vivo.Exogenous glucose treatment can significantly improve the color quality of tree peony cut flowers,prolong the life of in vases flowers,and promote the accumulation of soluble sugar and anthocyanin in the petals.The cut flowers of tree peony ’Luoyang hong’ mainly show the decrease of brightness,the increase of redness and chroma,which promote the accumulation of anthocyanin Cy3 G,Cy3G5G and Pn3 G content.Cut flowers of tree peony ’Tianyang’ are mainly manifested by decreased brightness,increased redness,yellowness and chroma,which promoted the accumulation of anthocyanin Pg3G5 G,Pg3G,Pn3G5 G and Pn3 G content.Exogenous glucose treatment continued to up-regulate the expression of Ps F3’H1,Ps5GT1 and Ps OMT1 genes.The up-regulated expression trend of genes was consistent with the rising trend of anthocyanin content.It is speculated that Ps F3’H1,Ps5GT1 and Ps OMT1 genes may be glucose signals The main gene that regulates the accumulation of anthocyanin in the petals of tree peony.Osmotic pressure can promote the rapid opening of tree peony cut flowers in a short period of time,mainly during the break period(S2)of the cut flowers to promote the accumulation of anthocyanin content and the expression of related anthocyanin glycoside synthesis genes.Mannose treatment inhibited the expression of Ps CHS1,Ps F3’H1,Ps DFR1,Ps ANS1,Ps5GT1 and Ps OMT1,and severely inhibited the opening of cut flowers and the accumulation of anthocyanin.It is not the main reason that exogenous glucose promotes the accumulation of tree peony anthocyanin by osmotic effect,it is mainly through the regulation of sugar signal.This paper clarified the characteristics of flower color development during the cutting process of tree peony cut flowers.Through research on phenotypic flower color,internal metabolites,anthocyanin composition,gene regulation,etc.,the main reasons why the flower color quality of tree peony cut flowers are not as good as in vivo are clarified.The effect of exogenous glucose on improving tree peony flower color was explored,and the regulatory effect of sugar signal on anthocyanin synthesis of tree peony cut flowers was clarified.Provide a theoretical basis for the development of post-harvest color preservation technology for tree peony cut flowers.