Study On The Application Of Controlled Atmosphere Storage And The Mechanism Of Different Postharvest Treatments For Keeping Fruit Firmness In The Ball Peach

In this study, the Ball Peach (Prumus persica L. Batsch) was treated by atmosphere-controlled (CA), Calcium treatment (Ca) and1-Methylcyclopropropene (1-MCP) in the refrigerator (0-1℃) storage temperature and firmness of the Ball Peach was systematically studied. By determining respiratory rate, fruit firmness, titratable acid content(TA), soluble solids content(SSC), Vitamin C content(VC), malonaldehyde content(MDA), relative electric conductivity, pectin content and pectinase activity(PG), starch content and amylase activity, superoxide dismutase activity(SOD), polyphenol oxidase activity(PPO) and weight loss, the characteristics of the Ball Peach under controlled atmosphere conditions were invested, the best percentage of different atmosphere in the Ball Peach were selected and the mechanism of keeping firmness by different treatment were invested as well, which provide theoretical and practical basis for storage of the Ball Peach and other horticultural products.The results showed that:1. In the refrigerator storage, the Ball Peach treated by controlled atmosphere during the storage, compared with contol, signigicantly inhibited respiratory rate and delayed respiratory peak, and delayed the decline of weight loss, fruit firmness, TA content, SOD activity, PPO activity, MDA content and relative electric conductivity, and therefore, CA storage can extend the storage period. The best atmosphere percentage was4%O2+5%CO2.2. There were differences among different atmosphere percentage about keeping the Ball Peach firmness, the result showed that:when the CO2contentration was given, with the increase of O2contentration, respiration intensity and TA content of the Ball Peach increased; when the O2contentration was given, the higher CO2contentration was given, the more obvious it became that respiration rate, SOD activity and PPO activity were controlled.3. The study about the influence of Ball Peach treated by different treatments (The four treatments in trial was4%O2+5%CO2、1%Ca2+and1μ1/L1-MCP, respectively) showed that different treatmeats can keep fruit firmness well. At42d, the firmness of fruit, treated by controlled atmosphere, was8.6kg/cm2, the increasing of the related enzyme was inhibited, the peak of PG activity and amylase activity was at35d,14d respectively. Calcium ions react with pectic acid generated pectate calcium, which can stabilize the pectin structure, furthermore, Calcium can ruduce the PG activity and keep fruit firmness. The study showed that calcium ions inhibited PG activity and amylase activity, and delayed the starch decomposing and the transformation of the original pectin to soluble pectin.1-MCP maintain the fruit firmness, at the42d, fruit firmness was7.2kg/cm2, PG activity and amylase activity was inhibited, the peak of PG activity and amylase activity was at28d,21d respectively. The best goup of keeping fruit firmness was CA storage. 4. The shelf-life study about the influence of Ball Peach treated by different treatments showed that CA, Ca and1-MCP can keep quality and extend the shelf life of the Ball Peach by affecting the physiological and biochemical. After the storage, the fruit-treated still owned high commodity value at the shelf life for nine days. CA and1-MCP were better.