| In order to explore the mechanism of 'brumal jujube' (Ziziphus jujube Mill) of maturation and scenescence and ethanol accumulation, We not only studied the quality and the post-harvest physiological and biochemical changes of 'brumal jujube' after treatment with hormone (ABA, GA and ethylene) during storage, but also investigated the effects of CAi (C027%~10%02+ 2~5%C02) and CA2: (7%~10%02, C02 2%) on the changes of fermentation volatiles, activity of enzymes (PDC, ADH) , the kind and content of sugar and organic acid during storage in this paper. Firstly announced the reason of ethanol accumulation under higher C02 level and discussed the mechanism of ethanol accumulation during the end of storage. The main results were as follows:'Brumal jujube' with higher respiration rate, which decreased slightly after harvest, and lower ethylene production, which had not the appearance of respiration and ethylene production peak, ethephon with different concentrations all increased respiration rate and the respiration rate increased with the raise of concentration ,which suggested 'brumal jujube ' was respiratory non-climactic fruits. The treatment of ethephon (1000 L.L-1) and ABA(100mg.L-1) evidently increased the respiration rate of green-mature fruit, there was no significant difference between treated with 100mg.L-1ABA and 1000 L.L-1ethephon; but ethephon significantly increased ethylene production, the activity of ACO and the content of ACC, the effects of ethephon treatment were higher than ABA . GA treatment restrained the respiration rate and ethylene production. 100mg.L-1ABA and 1000 L.L-1 ethephon evidently increased TSS and total titratable acidity acid content of green-mature fruit. The effect of ABA was more significantly than 1000 L.L-1ethephon, this suggested'ABA was the main hormone of influencing scenescence of'brumal jujube'fruit. The effects of ethephon treatment on redden rate and the content of total carotenoids were more evidently than ABA treatment, this indicated that the effect of ethephon on fruit color was significant.The content of ABA in white-mature 'brumal jujube 'increased and reached to the highest value during late storage ,On the contrary, the contents of IAA and GA were highest at first then decreased. The treatment of external ethephon (1000 L.L-1) and ABA(50mg.L-1) advanced the accumulation of internal ABA and the decrease of IAA and GA, the effects of ABA treatment are more obvious than ethephon's. this indicated effects of regulation on scenescence of fruit were through influencing the changes of internal ABA content.The relationship between different oxidative enzymes in the flesh and pericarp and ethanol accumulation in different maturity of 'brumal jujube' were investigated. The results showed that ascorbic acid oxidase activity in the flesh of 'brumal Jujube' became significantly higher than in pericarp with the development of maturity; but these activities of peroxidase , Polyphenoloxidase and phenylalanine ammonia-lyase in flesh were lower than in pericarp . During the development from green to half-red then to red, the lignin and fibre contents in pericarp gradually increased higher than in flesh; ethanol content also increased , acetaldehyde content reached to a peak during the red maturity stage and then declined. The results showed that accumulation ofethanol and lignin and fibre content increase in synchronization. The thicking of secondary cell wall may be one of the reason of ethanol accumulation.The activities peak value of CAT, PPO and POD were advanced and the activity of AAO gradually increased, the content of total phenol decreased sharply, the production rate of superoxide anion ,the content of MDA and H2O2 in flesh of 'brumal jujube' increased treated with ABA during storage, this showed ABA accelerated the scenescence of fruit, the effects of ABA on 'brumal jujube'fruit was contrary to GA. Compared to the flesh of fruit, the pericarp of 'brumal jujube' contained higher content of total phenol and H2O2 and lower content of Vc , the phenol in peri...
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