Department of Horticulture, Kangwon National University, Chuncheon 24341, Korea.
Interdisciplinary Program in Smart Agriculture, Kangwon National University, Chuncheon 24341, Korea.
Int J Mol Sci. 2021 Apr 23;22(9):4437. doi: 10.3390/ijms22094437.
Cold storage of peach fruit at low temperatures may induce chilling injury (CI). Pre-storage 1-MCP and high CO treatments were reported among the methods to ameliorate CI and reduce softening of peach fruit. However, molecular data indicating the changes associated with pre-storage 1-MCP and high CO treatments during cold storage of peach fruit are insufficient. In this study, a comparative analysis of the difference in gene expression and physico-chemical properties of fruit at commercial harvest vs. stored fruit for 12 days at 0 °C (cold-stored (CS), pre-storage 1-MCP+CS, and pre-storage high CO+CS) were used to evaluate the variation among treatments. Several genes were differentially expressed in 1-MCP+CS- and CO+CS-treated fruits as compared to CS. Moreover, the physico-chemical and sensory data indicated that 1-MCP+CS and CO+CS suppressed CI and delayed ripening than the CS, which could lead to a longer storage period. We also identified the list of genes that were expressed commonly and exclusively in the fruit treated by 1-MCP+CS and CO+CS and compared them to the fruit quality parameters. An attempt was also made to identify and categorize genes related to softening, physiological changes, and other ripening-related changes. Furthermore, the transcript levels of 12 selected representative genes from the differentially expressed genes (DEGs) in the transcriptome analysis were confirmed via quantitative real-time PCR (qRT-PCR). These results add information on the molecular mechanisms of the pre-storage treatments during cold storage of peach fruit. Understanding the genetic response of susceptible cultivars such as 'Madoka' to CI-reducing pre-storage treatments would help breeders release CI-resistant cultivars and could help postharvest technologists to develop more CI-reducing technologies.
低温冷藏桃果实可能会引起冷害（CI）。据报道，采前 1-MCP 和高 CO 处理是改善 CI 和减少桃果实软化的方法。然而，关于采前 1-MCP 和高 CO 处理在桃果实冷藏过程中相关变化的分子数据还不够充分。在这项研究中，对商业收获期和在 0°C 下冷藏 12 天的果实（冷藏（CS）、采前 1-MCP+CS 和采前高 CO+CS）的基因表达和果实理化性质的差异进行了比较分析，以评估处理之间的差异。与 CS 相比，1-MCP+CS 和 CO+CS 处理的果实中几个基因表达存在差异。此外，理化和感官数据表明，1-MCP+CS 和 CO+CS 抑制了 CI，延缓了果实成熟，比 CS 果实具有更长的贮藏期。我们还鉴定了在 1-MCP+CS 和 CO+CS 处理的果实中共同和特异表达的基因列表，并将其与果实品质参数进行了比较。还试图鉴定和分类与软化、生理变化和其他成熟相关变化相关的基因。此外，通过定量实时 PCR（qRT-PCR）对转录组分析中差异表达基因（DEGs）的 12 个代表性基因的转录水平进行了验证。这些结果为桃果实冷藏过程中采前处理的分子机制提供了信息。了解易感品种（如‘Madoka’）对减少 CI 的采前处理的遗传反应将有助于培育者释放抗 CI 的品种，并有助于采后技术人员开发更多减少 CI 的技术。
