Bell pepper is a model for studying the ripening process of non-climacteric fleshy fruit, during which numerous physiological changes occur. UV-C irradiation is an abiotic stress, which has an important influence on plant growth, development and ripening. We explored the influences of UV-C irradiation on physiological changes in bell pepper fruit during postharvest storage by measuring sensory quality, firmness and mass loss, and the underlying changes at the molecular level by combined transcriptome and metabolome analysis. Effects were detected on transcripts for numerous critical enzymes involved in fruit pigment accumulation, fruit texture change, fruit flavor and aroma production. Moreover, transcripts for several key enzymes and transcription factors involved in plant hormone pathways and their corresponding noncoding RNAs were identified and differential expression profiles were also analyzed. Components of a competing endogenous RNAs (ceRNA) regulatory network changed in response to UV-C irradiation and the relationships between them was analyzed. Thirty-one differentially expressed metabolites were identified. Combined transcriptome and metabolome analysis showed that the genes and metabolites that responded to UV-C were mainly involved in flavonoid, phenylalanine, tyrosine, tryptophan and phenylpropanoid biosynthesis. This study provides insights into bell pepper fruit physiology and the effects of UV-C irradiation on postharvest quality and enhances our understanding of the underlying mechanism whereby UV-C delays postharvest physiological changes in bell pepper fruit.

甜椒是研究非更年期肉质果实成熟过程的模型，在此过程中会发生许多生理变化。UV-C辐照是一种非生物胁迫，对植物的生长、发育和成熟有重要影响。我们通过测量感官质量、硬度和质量损失，以及结合转录组和代谢组分析在分子水平上的潜在变化，探讨了 UV-C 照射对采后贮藏期间甜椒果实生理变化的影响。检测到对参与水果色素积累、水果质地变化、水果风味和香气产生的许多关键酶的转录的影响。而且，鉴定了涉及植物激素途径的几种关键酶和转录因子的转录本及其相应的非编码 RNA，并分析了差异表达谱。竞争性内源性 RNA (ceRNA) 调控网络的组成部分响应 UV-C 照射而发生变化，并分析了它们之间的关系。鉴定了 31 种差异表达的代谢物。结合转录组和代谢组分析表明，响应 UV-C 的基因和代谢物主要参与黄酮类、苯丙氨酸、酪氨酸、色氨酸和苯丙烷类生物合成。