Effects of 1-MCP on Ethylene Synthesis,Cell Wall Degradation and Related Genes Expression in Passion Fruit
In order to illustrate the effect and underlying mechanism of 1-methylcyclopropene(1-MCP)treatment on room temperature storage of passion fruit,golden passion fruit was used as experimental material.Commercial mature passion fruit was treated by 1.2 μL/L 1-MCP and stored at(20±1)℃ for 12 d,and the untreated fruit was used as control.During storage,ethylene release rate,respiration rate,total soluble solid content,pectin content,cell wall degrading enzymes activities were measured every 3d.The expression levels of ethylene biosynthesis genes(ACS1 and ACO1)and cell wall-degrading enzyme encoding genes(PME1,XTH16/28/30,PG1 and GAL1)in passion fruit were analyzed.Compared with control,1-MCP treatment decreased ethylene release rate and respiration rate of passion fruit,and inhibited the expression of key ethylene biosynthesis genes ACS1 and ACO1.The contents of acid-soluble pectin and water-soluble pectin in 1-MCP treatment group were significantly higher and lower than that in control,respectively.It was also found that 1-MCP treatment reduced polygalacturonase and cellulase activities,and inhibited the expression of PME1,XTH/16/28/30 and GAL1.Moreover,a*and L in 1-MCP treatment group were significantly lower and higher respectively than that in control at the end of storage.There was no significant difference on total soluble solid and titrable acid contents between 1-MCP treatment and the control during the whole storage time.In conclusion,1-MCP inhibited endogenous ethylene synthesis in passion fruit by decreasing the expression of ethylene biosynthesis genes ACS1 and ACO1,and inhibited cell wall degradation by decreasing cell wall-degrading enzymes activities and reducing expression of encoding genes including PME1,XTH/16/28/30 and GAL1,thereby delaying the postharvest ripening process of passion fruit and demonstrating a good preservation effect on passion fruit.
万方数据
维普
