Pomegranate is sensitive to low temperature and is susceptible to chilling injury (CI), resulting in husk browning. The effects of Methyl jasmonate (MeJA), hot water treatment (HWT), and control treatments on the quality of pomegranate fruit during low temperature storage were investigated. The results showed that MeJA and HWT treatments could effectively inhibit the increase of browning index, color difference, relative conductivity, polyphenol oxidase (PPO) and peroxidase (POD) activities, maintain phenolic substances and the activity of phenylalanine ammonia-lyase (PAL). The browning index of MeJA treatment was 55.42 % lower than control treatment on the 70th day, the relative conductivity and MDA content were 24.32 % and 51.67 % lower than control treatment, respectively. Furthermore, MeJA treatment delayed the increase of PgPPO and PgPOD gene expression levels, upregulated the expression levels of PgPAL gene. Overall, MeJA treatment could improve antioxidant capacities, alleviate CI by regulating phenolic metabolism and gene expression levels.

中文翻译：

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茉莉酸甲酯减轻石榴果壳褐变并调节与石榴果实酚类代谢相关的基因的表达


石榴对低温敏感，易受冷害 （CI） 的影响，导致果壳褐变。研究了茉莉酸甲酯 （MeJA）、热水处理 （HWT） 和对照处理对石榴果实低温贮藏品质的影响。结果表明，MeJA和HWT处理能有效抑制褐变指数、色差、相对电导率、多酚氧化酶（PPO）和过氧化物酶（POD）活性的增加，维持酚类物质和苯丙氨酸解氨酶（PAL）活性。第 70 天，MeJA 处理的褐变指数比对照低 55.42 %，相对电导率和 MDA 含量分别比对照低 24.32 % 和 51.67 %。此外，MeJA 处理延迟了 PgPPO 和 PgPOD 基因表达水平的升高，上调了 PgPAL 基因的表达水平。总体而言，MeJA 处理可以通过调节酚类代谢和基因表达水平来提高抗氧化能力，缓解 CI。