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Jujube（Zizyphus jujuba Mill）and Eureka lemon（Citrus limon（L.）Burm.F.）are popular because of their good health and nutritional value,however,they are sensitive to low temperature during its cold storage,causing chilling injury,leading to quantitative and qualitative losses,as well as reduced economic value.Recently,exogenous polyamines have been considered as an environmentally friendly treatment to maintain the postharvest quality of horticultural products.In this study,the jujube and lemons were immersed either in polyamine solutions [1 mmol/L putrescine（PUT）,1 mmol/L spermidine（SPD）,or 0.5 mmol/L PUT + 0.5 mmol/L SPD（combined）] or in distilled water（control）.The morphology,cellular structure（using transmission electron microscopy）,chilling injury（CI）index,total soluble solids（TSS）,titratable acid（TA）,malondialdehyde（MDA）contents,and membrane permeability,as well as the peroxidase（POD）and polyphenol oxidase（PPO）activity,was measured after 0,7,14,21,28,and35 days（jujube）and 0,15,30 and 45 days（lemons）of storage at-2 ± 0.5°C.In jujube,results demonstrated that exogenous PUT or SPD treatment significantly alleviated the CI symptom of jujube such as spongy brown,mesophyll collapses,cell structure,and cell integrity,suppressed the change in fruit color from green to red,maintained higher levels of TSS and TA,decreased MDA accumulation,compared to control.What’s more,the relative antioxidant enzymes activity of PPO and POD were enhanced by PUT and/or SPD treatment.Particularly,the combination of PUT and SPD effectively maintained the quality of the jujube fruits during storage by enhancing CI tolerance and decreasing MDA accumulation.In lemon,results indicated that the exogenous PA treatment significantly delayed CI symptoms such as pitting,membranous staining,and brown skin on lemon fruits.Furthermore,PUT,SPD,PUT + SPD have inhibited the increase of MDA and electrolyte leakage（EL）levels and maintained higher amounts of TSS and TA and POD and PPO activity in PA-treated fruit compared to control.The PUT,SPD,and combined treatments exhibited significantly reduced EL and less evidence of CI.In summary,this research work indicates that the synergistic effects of PUT and SPD protected the fruit from chilling injury and maintained the postharvest quality of both jujube and lemon better than PUT or SPD alone did.Thus,this study proved the exogenous PA role in inhibiting CI and maintaining of jujube and lemon quality at a nonfreezing temperature during storage.Furthermore,it provides a potentially easy way to reduce the disorder loss in the postharvest industry.