Effects Of 1-MCP Treatment On Quality,Antioxidative Systems And Anthocyanin Biosynthesis In Plum (Prunus Salicina Cv.Taoxingli) Fruit

The effects of 1-MCP?1-methylcyclorpropene?treatment on quality,antioxidative systems and anthocyanin biosynthesis in plum?Prunus salicina cv.Taoxingli?during storage at low temperature were investigated in this paper,after the harvested plum were treated with6.0?L/L 1-MCP or water?as control?at room temperature?23±2°C?for 12 h,and then stored at 10±0.5?.The main results were as follows:1?1-MCP treatment significantly reduced the respiration rate of plum early in storage and delayed the peak of respiration rate.Meanwhile,1-MCP treatment effectively reduced weight loss and better maintained SSC and TA,resulting in increased contents of fructose,glucose,sorbitol,and malic acid,and also reduced decay incidence during storage.However,there was no significant effect on firmness and color.It was indicated that 1-MCP treatment could delay the ripening process and was beneficial to retaining the quality of plum fruit‘Taoxingli'during storage.2?1-MCP treatment increased the total phenolic content of plum fruits,maintained the content of flavonoids,but inhibited the increase in anthocyanin content.Moreover,the treatment effectively reduced the production rate of superoxide radical and the accumulation of hydrogen peroxide?H₂O₂?,significantly increased the activities of superoxide dismutase?SOD?and peroxidase?POD?,and decreased the activities of polyphenol oxidase?PPO?and lipoxygenase?LOX?,as well as reduced the accumulation of malondialdehyde?MDA?later in the storage period.It was indicated that 1-MCP treatment could enhanced the antioxidant ability accompanied with decline in the damage of reactive oxygen species.3?HPLC analysis of the flesh of plum cv.‘Taoxingli'only revealed the presence of two main anthocyanin peaks:cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside.1-MCP treatment delayed increases in these anthocyanins during storage.Determination of the expression of genes involved in anthocyanin biosynthesis was conducted using RT-qPCR.1-MCP treatment remarkably suppressed the expression of synthesis-related structural genes including PsPAL,PsCHS,PsCHI,PsF3H,PsDFR,PsANS,and PsUFGT,as well as the transcription factor PsMYB10 early in storage,and then stimulated the expressions of PsPAL,PsCHS,PsCHI,PsF3H,PsUFGT and PsMYB10 later in the storage period.It indicated that1-MCP treatment effectively regulated anthocyanins biosynthesis in plum,which significantly delayed the accumulation of anthocyanins during storage,but 1-MCP treatment did not have a material impact on fruit quality in fully ripe plum fruit with respect to anthocyanin accumulation via anthocyanin biosynthesis during storage at lower temperature.