Transcriptome analysis of fresh-cut kiwifruit treated with slightly acidic electrolyzed water (SAEW) and 1-methylcyclopropene (1-MCP)

Abstract Fresh-cut kiwifruit is difficult to store due to the characteristics of thin and juicy rind, which results in the great limitation of development and utilization. The aim of the study was to evaluate the effect of slightly acidic electrolyzed water (SAEW) combined with 1-methylcyclopropene (1-MCP) on shelf life quality of fresh-cut kiwifruit by transcriptome technology. The results showed that SAEW or 1-MCP treatment suppressed ethylene production, respiratory rate, soluble solid content (SSC), polyphenol oxidase (PPO) and improved titratable acid content (TAC), total phenols content (TPC), total chlorophyll content (TCC), peroxidase (POD) and phenylalanine ammonia lyase (PAL) activities comparing with the untreated samples. There were 2754 differentially expressed genes (DEGs) between the combined treatment and the control on day 6. GO function annotation results showed that the related genes involved in cell membrane composition in samples might be involved in protein phosphorylation under the action of protein kinase genes. KEGG enrichment analysis showed that 715 DEGs were significantly enriched in 111 metabolic pathways on day 6 after combined treatment. In ethylene signaling pathway, expression levels of ETR and ERF1 were down-regulated, which proved that 1-MCP inhibited ethylene reaction by binding to ethylene receptors. Genes expression levels of SnRK2, MPK3/6, and BAP31 related to MAPK signaling pathway and protein processing in endoplasmic reticulum pathway were up-regulated, and the combined treatment had a positive regulatory effect on fruit defense during storage. In plant-pathogen interaction pathway, genes expression levels of MKK45 were down-regulated that proved the production of ROS was suppressed by combined treatment, consequently improving disease resistance of fresh-cut kiwifruit. Hence, the combination treatment of SAEW and 1-MCP may be a proven and effective technology to retain higher quality and nutritive properties of fresh-cut kiwifruit.