1-MCP处理对“彩虹1号”和“陆奥”苹果贮藏特性和相关基因表达水平的影响

Effects of 1-MCP on the Storage Characteristics and Expression Levels of Related Genes in ‘Caihong 1’ and ‘Mutsu’ Apple

摘要:

该研究以“彩虹1号”和“陆奥”苹果为试材，研究了1-MCP（1-甲基环丙烯）处理对这两个品种贮藏期间硬度、乙烯释放速率、失重率、挥发性物质以及乙烯生物合成和细胞壁降解相关基因的表达量的影响。结果表明：与对照果实相比，1-MCP处理能够显著降低“彩虹1号”果实失重率，延缓乙烯释放高峰出现，维持果实较高硬度。对照果实乙烯峰值出现在贮藏期60 d，乙烯释放量为74.13 μL/(kg•h)，1-MCP处理果实乙烯峰值出现在贮藏期90 d，乙烯释放量为41.61 μL/(kg•h)。“陆奥”苹果贮藏期间，1-MCP处理延缓了果实失重及乙烯释放速率。通过对相关基因的表达量分析发现，1-MCP处理的“彩虹1号”果实中乙烯合成基因MdACO、MdACS-1，细胞壁降解基因MdPG、MdXTHB表达量均明显降低，而“陆奥”果实中的细胞壁降解基因只有MdXTHB和MdEXPA8受到了抑制。综上所述，1-MCP能够明显降低“彩虹1号”果实中的乙烯释放速率，延缓了果实软化，延长其贮藏期，适合作为该品种果实的采后保鲜处理。

Abstract:

The effects of 1-MCP on the firmness, ethylene release rate, weight loss rate, volatile substances, and expression of genes related to ethylene biosynthesis and cell wall degradation of ‘Caihong 1’ and ‘Mutsu’ apple during storage were investigated. Compared with control treatment, 1-MCP treatment could significantly reduce the weight loss rate of the ‘Caihong 1’ fruit, delay the peak of ethylene release, and maintain high fruit firmness. The peak value of ethylene in the control fruit was 74.13 μL/(kg•h) on day 60 of storage, while that in the 1-MCP treated fruits was 41.61 μL/(kg•h) on day 90 of storage. Treatment with 1-MCP delayed the weight loss and ethylene release rate of ‘Mutsu’ apples during storage. By analyzing the expression of related genes, the expression levels of the ethylene synthesis genes, MdACO and MDACS-1, and cell wall degradation genes, MdPG and MdXTHB, were found to be significantly decreased in the 1-MCP-treated ‘Caihong 1’ fruit; however, only the expression of the cell wall degradation genes, MdXTHB and MdEXPA8, were inhibited in the ‘Mutsu’ fruits. In conclusion, 1-MCP can significantly reduce the ethylene release rate of the ‘Caihong 1’ fruit, delay fruit softening, and prolong the storage period of the fruit. Thus, 1-MCP is a suitable post-harvest preservation treatment for fruits of this variety.