Abstract
Rosa species possess significant economic and medicinal value and have been utilized in traditional medicine, essential oil production, and as landscape plants. Nevertheless, the precise mechanisms underlying floral scent formation in rose remain poorly understood, impeding the genetic enhancement of this trait. To address this knowledge gap, we performed an integrated transcriptome and metabolome analysis. We selected 12 floral scent components and identified 1,264 differentially expressed genes based on phenotypic differences. Weighted gene co-expression network analysis (WGCNA) revealed 702 genes potentially associated with floral scent formation. Of these, seven highly expressed genes were selected. Subsequently, the protein-protein interaction (PPI) network and topology analysis algorithm of the 702 genes identified 21 hub genes. By integrating the highly expressed genes with PPI hub genes, 26 candidate genes were selected and predicted to play pivotal roles in floral scent formation. Eight of these candidate genes have been directly or indirectly implicated in floral scent formation, thereby supporting the reliability of the candidate gene predictions. Furthermore, candidate genes involved in amino acid metabolism (ISS1, AS1, AG118, AO, HISN8, and HMGCL), starch and sucrose metabolism (TPPA and SUS2), sulfur metabolism (APK1 and APR1), and citrate cycle (FUM1) may contribute to the provision of precursors. Notably, TPPA and SUS2 may contribute to the precursor metabolism for terpenoid biosynthesis. Additionally, F3GT1 and UGT74AC may be involved in terpenoid biosynthesis. The ISC2 and ISS1 may play key roles in aromatic compounds biosynthesis. Furthermore, AUX22D, AUX22, ARG7, and GPAT2 may encode signaling molecules that regulate floral scent formation. A novel gene, LOC112189920, with an unknown function, may also be associated with floral scent formation.