Analysis on the Preservation Effect of Melatonin on Cut Chrysanthemum

TIAN Yunfang; CHU Zhigang; CHEN Lipei; HE Yixin; LIU Xiaojuan; FAN Chunli

doi:10.15933/j.cnki.1004-3268.2025.01.012

Abstract：In order to improve the storage and transportation resistance of cut chrysanthemum,fresh cut flowers of Youxiang were soaked in distilled water,basic vase solution(30 g/kg sucrose+250 mg/L 8-hydroxyquinoline+200 mg/L citric acid),melatonin solution(20 µmol/L)and basic+melatonin compound solution(20 μmol/L melatonin+basic vase solution)to explore the preservation effect of melatonin on cut chrysanthemum.Based on the previous results of fresh-keeping effect,three kinds of cut chrysanthemum Youxiang,Huangxiao and Baizhou were used as experimental materials,and three treatments were set up,light group(light 16 h/dark 8 h,distilled water),dark stress group(light 0 h/dark 24 h,distilled water)and dark relief group(light 0 h/dark 24 h,20 μmol/L melatonin),to study the alleviation effect of melatonin on leaf yellowing and senescence under dark stress.The results showed that,exogenous melatonin obviously delayed the flower diameter opening,improved water balance value and pigment content of cut chrysanthemum Youxiang,slowed down the change rate of fresh quality of cut flowers,enhanced the activities of SOD(superoxide dismutase)and POD(peroxidase),increased the content of soluble protein and decreased the relative electrical conductivity.Compared with the control,compound solution had the best preservation effect on Youxiang cut flowers(After 7 days of treatment,the average flower diameter was 7.11 cm,which was the smallest,and the flowers could continue to bloom),followed by 20 µmol/L melatonin and basic vase solution.For dark treatment,melatonin treatment increased the contents of chlorophyll and carotenoid in three cut chrysanthemum leaves under dark stress,delayed the degradation rate of soluble protein,and decreased the relative electrical conductivity and malondialdehyde content.On the 7th day of storage,the relative conductivity and malondialdehyde content of cut chrysanthemum in dark relief group decreased the most compared with that in dark stress group,with Youxiang decreased by 13.76％and 12.12％,Huangxiao by 17.35％and 12.47％,and Baizhou by 10.64％and 13.28％,all reaching significant levels(P＜0.05).20 µmol/L melatonin could alleviate the dark stress in cut chrysanthemum leaves.It is concluded that melatonin can decrease the content of MDA by enhancing the activity of antioxidant enzymes in cut chrysanthemum,so as to alleviate the dark stress and prolong the green period of leaves,which provides theoretical basis for the application of melatonin in long-distance transportation of cut chrysanthemum.