Effect Of 1-MCP In Combination With Different Temperatures On The Physiology And Quality Of Apricot Fruit

In the history of Chinese fruit tree cultivation,apricot trees have long occupied a heavy share of the agricultural economy because of their advantages in improving the environment,preventing land desertification and driving economic growth.The main reasons affecting the development of the apricot industry in China are the high failure rate of apricot trees,the short and concentrated supply period of apricot fruits and the lack of storage and transportation.The apricot fruit ripens in the hot season,has a short harvest period,is highly respiratory and metabolic,and is prone to water loss and spoilage when stored at unsuitable temperatures,increasing the chances of infection by pathogenic microorganisms,wasting resources and causing huge economic losses.This paper uses 1-MCP treatment in combination with 1-Methylcyclopropene to maintain good quality.In this paper,we used 1-MCP treatment in combination with four different temperatures（（-1）-0℃,0-2℃,2-4℃,4-6℃）to analyse the effects of postharvest storage on the quality and physiological changes of apricot fruit.The main findings were as follows:（1）To investigate the effect of different concentrations of 1-MCP on the post-harvest quality of apricot fruit.The apricots were fumigated with 1-MCP at 0.5?L/L,1?L/L and 2?L/L for 24 h and then aired for 1h.The apricots were stored at room temperature（22±3）℃and the quality indicators were determined.The results showed that the 1-MCP treatment at 1?L/L was the most effective in slowing down the decline of apricot fruit hardness compared with the other groups,and the hardness could still reach 15.3 N by the end of storage.The storage quality of the apricots was also maintained at a high level.（2）To investigate the effects of 1-MCP treatment combined with different temperature treatments on the quality and physiology of apricot fruit.Through comparative screening,apricot fruits were fumigated with1-MCP at a concentration of 1?L/L,and the control group was treated with no 1-MCP.Both treatment and control groups were stored at four temperatures（（-1）-0°C,0-2°C,2-4°C,4-6°C）.The results showed that all treatment groups were able to maintain the quality of apricot fruit,with the 1-MCP treatment combined with（-1）-0℃having the best storage effect,significantly inhibiting the cell membrane permeability of apricot fruit and delaying the decline of hardness,titratable acid and ascorbic acid,keeping the fruit fresh at49 d,and reducing the rate of decay,weight loss and the incidence of cold damage.（3）To investigate the effect of 1-MCP treatment combined with different temperatures on the metabolism of reactive oxygen species in apricot fruit after harvest.The treatments were the same as（2）.All treatment groups were able to maintain the balance of reactive oxygen metabolism in apricot fruit to some extent and reduce the damage of reactive oxygen to apricot fruit.The results showed that 1-MCP treatment combined with（-1）-0℃was the most effective,effectively increasing Superoxide Dismutase（SOD）,inhibiting the rate of Superoxide radical（O₂^-·）production,Hydrogen Peroxide（H₂O₂）It also inhibited the increase of superoxide radical（O₂^-·）production rate,the increase of hydrogen peroxide（H₂O₂）content,the decrease of Catalase（CAT）and Peroxidase（POD）activities,significantly reduced the accumulation of Malondialdehyde（MDA）content,and increased the storage effectiveness of apricot fruits.（4）To investigate the effect of 1-MCP treatment combined with different temperatures on post-harvest cell wall metabolism of apricot fruit.The treatments were the same as（2）.The results showed that the storage quality of apricot fruit was maintained in all treatment groups,with 1-MCP treatment combined with（-1）-0℃being the most effective in inhibiting Cellulase（Cx）,Polygalacturonase（PG）,Pectin methylesterase（PME）The increase in the activity of pectin andβ-Glucosidase（β-GLU）,reduces the degradation capacity of Proto-pectin（PP）content and increases the Soluble pectin（SP）content.