| Jujube fruit were studied their postharvest physiological properties, quality and storability under different storage conditions in order to determine the suitable storage conditions and storage time for this fruit. In the experiment, Jujube fruit were stored in controlled atmospheres (CA) of 5% O2 plus 0% CO2 or 10% O2 plus 0% CO2, dynamic CA (70% O2 for 7 days, then transferred to 5% O2) at -1 °C or in air at 25 and -1 °C, respectively. The relative properties, such as polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), polygalacturonase (PG), lipoxygenase (LOX) and malondialdehyde (MDA) content as well as membrane integrity of jujube fruit were analyzed during different storage conditions, and the relationship between the storage condition and senescence, browning, softening and storability of jujube fruit were revealed. Meanwhile, the total soluble solids content, titratable acidity, ethanol and ethyl acetate content, color, contents of pigment, firmness, vitamin C content of the fruit were also measured in all storage periods. The results will be beneficial to provide integrative technologies for commercial storage of jujube fruits and showed as following:1. Effects of different storage conditions on quality of jujube fruit: Vc contents of jujube fruit decreased with storage time and CA treatment could maintain Vc contents effectively. Soluble solids content (SSC) and titratable acidity content were not significantly affected by CA treatments. 70% High O2 treatment was the most effective in maintaining peel color, anthocyanin and chlorophyll contents and preventing peel browning compared to other treatments. High O2 treatment could also reduce ethanol content significantly especially during the early storage periods.2. Physiological responses of jujube fruit to different storage conditions: (1) PGwas a major factor influencing fruit softening. The result of this experiment showed that there exists endo-PG and exo-PG in jujube fruit and the softening of fruit was notably related to PG activity. The activity of endo-PG and exo-PG increased with the ripening of jujube fruit and CA with 5% O2 plus 0% CO2 was beneficial for reduce PG activity of jujube fruit. (2) The result of this experiment showed that browning potential of jujube fruit was little related to PPO activity, but notably to membrane integrity and MDA content. MDA content influenced fruit browning and CA storage could reduce MDA content and maintain membrane integrity effectively especially during the early storage periods. (3)The SOD activity of jujube fruit was very low at harvest and increased rapidly with the ripening of the fruit stored at 25℃. (4) The PAL activity of jujube fruit decreased with the prolonging of storage time under different conditions.3. The physiological factors influencing the storability of jujube fruit: CA storage could induce some pro-and anti-oxidant enzymes in jujube fruit. Data in this study showed that the decrease of POD and CAT activity associated with the increase in LOX activity might contribute to the accumulation of ROS and lipid peroxidation of jujube fruit during storage at -1 ℃. CA treatment induced SOD and POD activities of jujube fruit during storage.4. The beneficial conditions for storage of jujube fruit: CA with 10% O2 plus 0% CO2 was beneficial for jujube storage. CA (10% O2+ 0% CO2) could delay fruit senescence, reduce fruit decay and browning, maintain quality and prolong storage period. In combination CA with fungicide was beneficial for storing jujube fruit. CA storage in combination with STROBY or DECCOZIL showed to be better result for controlling decay and prolonging storage life in comparison with CK. The effect of STROBY was better than DECCOZIL.5. Changes in the activities of pro- and anti-oxidant enzymes in jujube fruits inoculated by C. laurentii or A. alternate: The biochemical and physiological changes induced by C. laurentii ox A. alternate in jujube fruits were studied at 25°C or-1℃. The results showed th...
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