Effect Of 1-MCP On The Rot Disease Of Hanfu Apple After Storage And Its Control Technology

Hanfu apple is cold-resistant,sour and juicy.According to statistics,the national planting area exceeds 11.5 million hm~2.The annual output can reach 1.104 million tons,which beyonded the demands of the current sales so that it has to be store.However,the disease will cause damage during storage.In order to control the rot disease of the Hanfu apple,this study used Hanfu apple as experimental material to separate and purify the main pathogens from rot Hanfu apples,and to study the causative ability of pathogenic bacteria.1-Methylcyclopropene(1-MCP)was used as antibacterial substance to investigate its inhibitory effect on pathogenic bacteria.The effects of different 1-MCP products before 1-MCP storage,different concentrations after storage,and two treatments before storage on the shelf rot rate,related enzyme activities,physiological indexes,nutritional quality and volatile components of Hanfu apples were investigated.The optimal concentration and treatment time of 1-MCP were determined,which provided the best protection for the disease control and shelf quality of Hanfu apple,and provided a theoretical basis for the 1-MCP control technology of Hanfu apple.The study of the isolation and identification and the causative ability of the pathogens of rot disease on Hanfu apple:the pathogenic bacteria of Alternaria and Aspergillus were isolated from the rotted Hanfu apples.The causative activity of Aspergillus was greater than that of Alternaria.The results of 1-MCP bacteriostatic experiment showed that the minimum inhibitory concentration of 1-MCP against Alternaria was 8?L/L and the minimum inhibitory concentration against Aspergillus was 9?L/L under vitro.In the vivo inoculation experiment,the effect of 5?L/L 1-MCP treatment to control the diameter of apple lesions was most significant.The inhibition rates against Alternaria and Aspergillus were 18.17%and 27.31%at 6 d,respectively.In this experiment,the optimal1-MCP concentration for controlling apple rot was 5?L/L.The effect of different 1-MCP products and 1-MCP treatment after cold storage on shelf quality showed that:the?-cyclodextrin-embedded 1-MCP showed better effects on reducing fruit rot rate,lowering respiratory strength,maintaining hardness,and lowering LOX enzyme activity in the experiment.The cyclodextrin-embedded 1-MCP can effectively slow down the ethylene production rate of Hanfu apples,and at the same time,it was better to delay the reduction of Vc.The 3 or 5?L/L 1-MCP treatment after cold storage can reduce the decay rate and ethylene production rate,maintain fruit firmness and CAT activity of Hanfu apples.But it has little effect on respiratory strength and titratable acid content.Among them,5?L/L treatment has a significant effect on maintaining TSS,Vc,and reducing LOX activity.The effects of 1-MCP treatment on the regulation of rot and shelf quality of Hanfu apple showed that:compared with CK group,1-MCP treatment group can significantly reduce the decay rate of Hanfu apples,increase the activity of POD,PPO and PAL,and significantly reduce the respiratory intensity and ethylene release rate of Hanfu apple during shelf life;The nutritional quality of Hanfu apples was maintained at a good level,slowing down the rate of decline of TSS,Vc and titratable acid content;The hardness of Hanfu apples was maintained.Compared with the 1-MCP treatment group before storage,the 3?L/L and 5?L/L treatment groups after storage could significantly inhibit fruit rot and control the rot rate within 20%.After significant analysis,there was a significant difference between 1-MCP treatment before and after storage at 14 to 28 days.At the same time,the 3?L/L and 5?L/L treatment groups could significantly increase the activity of POD,PPO and PAL,and effectively maintain the aldehyde content.At 28 d,compared with the 5?L/L treatment group after storage,2-hexenal and hexanal content of it was 832 ng/m L and 196 ng/m L higher than that of 1-MCP treatment group before storage respectively,and 2-hexenal content of it was 159 ng/m L higher than that of the 3?L/L treatment group after storage,and hexanal content of it was 395 ng/m L lower than that of the 3?L/L treatment group after storage.The hardness of the 5?L/L treatment group after storage was the lowest at 28 d.1-MCP treatment inhibited fruit respiration,but there was no significant difference between the 3 and 5?L/L treatment groups.Both 1-MCP treatment before and after storage could reduce the rate of ethylene production.At 28 days,the 1-MCP before storage showed a significant difference from the 5?L/L treatment group after storage.The rate of soluble solids,titratable acid and Vc decreased in the 1-MCP treatment group before storage was lower than that in the other two treatment groups.There was no significant difference between the 1-MCP and other treatment groups before storage at28 d.1-MCP treatment before storage can regulate physiological indicators and storage quality.1-MCP treatment after storage can significantly inhibit the occurrence of rot disease and improve the activity of disease-resistant enzymes.It was indicated that 1-MCP can achieve physiological regulation before storage and control disease after storage.In summary,the treatment of 1?L/L 1-MCP before storage and 5?L/L 1-MCP treatment at the time of storage were the best for the disease control of Hanfu apples during shelf life.In the 28 d shelf life,the decay rate can be controlled within 16.66%,and the shelf life was extended by 10-15 days.