| The water loss of cut flowers is mainly through the leaf stomata during the postharvest period,which can be slowed down by modulating stomatal aperture,and their freshness and quality can be maintained.Unlike numerous cut flowers,the cut Zantedeschia hybrida flowers have no leaves during the postharvest period,and its water loss is likely to be via the stomata in their non-leaf organs and tissues.However,there is still a lack of research on the characteristics and regulation of non-leaf stomata in cut flowers.Therefore,this thesis focused on the stomatal distribution and morphological characteristics in different parts of cut Zantedeschia hybrida flowers,and physiological and molecular mechanism of light response were investigated,which aimed to provide new ideas and strategies for postharvest treatment and preservation of the cut Zantedeschia hybrida flowers and even other cut flowers.The main results are as follows:（1）Stomata were found in different parts of the abaxial spathe,adaxial spathe and stem of 3 varieties of cut Zantedeschia hybrida flowers.Among them,the stomatal density in the middle abaxial spathe was the largest,and the stomatal density in the stems decreased gradually along the morphological upper to the lower part.（2）The stomatal size and shape were different in the same part of each variety and different parts of the same variety.The largest relative stomatal area is‘Florex Gold’（2.7%）,followed by‘Hot Chocolate’（1.6%）,and the lowest is‘Pink Persuasion’（1.3%）.The stomatal area of the lower stem surface was the largest in the different parts of each variety,but the relative stomatal area of the lower stem surfaces was relatively low.In addition,the stomatal shape of each variety was oval or long oval.（3）Under 50,100 and 150μmol m-2 s-1 of white light,the water loss rate of‘Florex Gold’was significantly higher than that in dark,of which the cut flowers lost water the fastest under 100μmol m-2 s-1 white light.Additionally,compared with dark treatment（control）,the blue,red,green and white illumination treatments with light intensity of 100μmol m–2 s–1could promote the water loss of the cut flowers,among them the blue light had the strongest promoting effect.（4）Within continuous illumination for 9 h,the stomatal opening rate and stomatal aperture of the abaxial spathe of cut Zantedeschia hybrida‘Florex Gold’flowers were both increased first and then decreased with the illumination time,and the stomatal opening rate and stomatal aperture reached the maximum peak at 6 h and 3 h of illumination,respectively.In addition,the stomatal conductance of abaxial spathe was significantly higher than that of the adaxial spathe,and the stomatal conductance with blue light of the cut flower was the highest,followed by white light and the red light is the lowest.（5）Based on the RNA-seq analysis of the spathe of cut Zantedeschia hybrida flowers‘Florex Gold’with white light treatment,1158,903 and 1689 genes were differentially expressed only at the 1,3 and 6 h of illumination,respectively.The KEGG enrichment analysis indicated that the main metabolic pathways involved were metabolic pathways,biosynthesis of secondary metabolites,photosynthesis,photosynthesis-antenna proteins and plant hormone signal transduction.Further analysis of the expression characteristics of the important genes related to stomatal movement,such as photoreceptors genes（PHOTs,PHYs and CRYs）,K+channels genes（KATs,NHXs and TPKs）and aquaporins genes（PIPs and TIPs）,revealed that some genes were inhibited by white light,while some genes were specifically induced by white light. |
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