Previously, wax + cinnamaldehyde (WCA) was proven to be able to effectively alleviate fruit decay and induce resistance in harvested Satsuma mandarin (Citrus unshiu). However, the potential molecular mechanism is largely unknown. In the present study, transcriptomics, metabolomics and biochemical analyses were combined to clarify this process. Transcriptomic analysis revealed that the expression of genes involved in secondary metabolites and related to pathogenesis and the phenylpropanoid pathway were significantly influenced by WCA treatment. In addition, metabolite profiling revealed that metabolites in the phenylpropanoid pathway were also predominantly impacted after WCA treatment. Correspondingly, enzymatic activities and gene expression involved in the phenylpropanoid pathway were positively regulated, especially in the first 24 h, resulting in increased levels of total phenolics, flavonoids and other secondary metabolites. Fruit inoculation experiments showed that WCA treatment significantly reduced the development of citrus green mold and sour rot while having no adverse effects on the edible quality of the tested citrus fruit. Our study confirms the potential role of WCA exposure in citrus to induce resistance through the phenylpropanoid pathway.

此前，蜡+肉桂醛（WCA）被证明能够有效缓解收获的萨摩蜜柑（Citrus unshiu ）的果实腐烂和诱导抗性). 然而，潜在的分子机制在很大程度上是未知的。在本研究中，结合转录组学、代谢组学和生化分析来阐明这一过程。转录组学分析显示，参与次级代谢产物和与发病机制和苯丙素途径相关的基因表达受到 WCA 处理的显着影响。此外，代谢物分析表明，苯丙烷途径中的代谢物在 WCA 处理后也受到主要影响。相应地，参与苯丙烷途径的酶活性和基因表达受到正向调节，尤其是在前 24 小时，导致总酚类物质、类黄酮和其他次级代谢产物水平升高。果实接种实验表明，WCA 处理显着减少了柑橘绿霉和酸腐病的发生，同时对供试柑橘果实的食用品质没有不利影响。我们的研究证实了 WCA 暴露在柑橘中通过苯丙素途径诱导抗性的潜在作用。