The Effects Of Hydrogen-rich Water Pretreatmenton On The Vase Life Of Cut Carnations And The Research Of Mechanisms

As a selective antioxidant and signal molecule, hydrogen has caused wide public concern in medical applications over recent years. Peroxide stress accelerates the senescence of cut flowers. Whether hydrogen-rich water pretreatment could delay cut flowers senescence and the mechanism of action have not been reported. In this experiment, we have used different concentrations of hydrogen-rich water were chosento pretreat cut carnation flowers(Dianthus caryophyllus) and study the effects to the physiological indexes, such as vase life, fresh weight, flower diameters and so on. Then pick out the most appropriate HRW concentration. On the basis of the preliminary experiment, we used the 10% HRW to pretreat fresh cut carnations and analyze the peroxide stress and the accumulation of metabolites during the five developmental stages(I: preopening, II: opening, III: beginning of wilting, IV: wilting, V: total wilting)of cut carnations. The results were followed.(1)By setting deionized water as control, we used 1%,10%,25%,50% and 100% hydrogen-rich water to pretreat cut carnations and found that 10% hydrogen-rich water pretreatment significantly extended carnations’ vase life, slowed down the rate of fresh weight decreasing and flower wilting during the later period of vase-holding,. It extended the carnations’ full bloom period, and then postpone senescence progress.(2)We analyzed the electronic leakage, Malondialdehyde(MDA) content, Catalase(CAT), Peroxidase(POD), Ascorbate peroxidase(APX) and Superoxide dismutase(SOD) activities of control and 10% hydrogen-rich water pretreatment carnations. We found that 10% hydrogen-rich water pretreatment’s electronic leakage was significantly lower than control at Stage III and IV. Compared with control group, hydrogen-rich water pretreatment’s MDA content dropped significantly at Stage III and IV, CAT and APX activity significantly increased at Stage IV, POD activity had an obvious increase at Stage V. But there was no significant increase observed in SOD activity. 10% hydrogen-rich water pretreatment could intensively inhibit the respiratory intensity,postponed the appearing time of ethylene and respiratory climacteric.(3)Using the GC-MS technology, we analyzed the metabolites changes during the carnations’ five developmental stages.We found 76 metabolites in carnation petals, including 22 organic acids, 17 amino acids, 23 sugars, 7 sugar alcohols, 3 fatty acids and 3 other compounds. With the partial least squares-discriminant analysis, 18 relative metabolites in petals are arranged on the basis of VIP. 10% hydrogen-rich water pretreatment’s ethanolamine content significantly improved at Stage I and II, malic acid and citramalic acid content were significantly higher than control at Stage III, 5-oxo-proline,some sugars and Myo-inositol content were significantly lower than control at Stage V.