## 4 Discussion
Tissue-related volatile markers may also aid in the chemotaxonomic authentication of Phoebe-derived products. Furthermore, these insights can support aroma-oriented breeding strategies or metabolic engineering to enhance desirable scent traits in wood materials or ornamental cultivars of Lauraceae species. Overall, our findings demonstrate that the volatile profiles of _P. zheman_ and _P. chekianensis_ are shaped by a complex interplay between tissue identity, species background, and ecological function. By combining GC-MS metabolomics, rOAV quantification, KEGG pathway enrichment, and flavoromics interpretation, we provide an in-depth framework for dissecting aroma-related chemical diversity in woody plants. These insights have important implications for the conservation, commercial utilization, and metabolic engineering of aromatic tree species. It is worth noting that not all volatile compounds could be annotated in the KEGG database, particularly some sesquiterpenes and norisoprenoids. These unmapped compounds were excluded from the enrichment analysis, which may have limited the pathway coverage. Nevertheless, the annotated subset provided meaningful insights into the major metabolic routes underlying tissue- and species-related volatile differences. However, it should be noted that the KEGG enrichment analysis in this study was based solely on the presence and relative abundance of annotated metabolites. Therefore, the functional interpretations drawn from pathway enrichment should be viewed as suggestive of possible metabolic trends, rather than conclusive evidence of pathway activation or gene regulation, such as enhanced terpenoid biosynthesis. Future transcriptomic or flux-based analyses are needed to validate these metabolic inferences. Despite the in-depth analysis, this study is limited to two species and two organs under a single environmental condition. Further multi-seasonal, multi-site, and transcriptome-integrated investigations will be valuable for confirming the generality and underlying regulation of the volatile patterns observed here. Compared with previous studies of volatile metabolomes in aromatic trees across different regions, such as _Cinnamomum camphora_ in Zhejiang [34] and _Litesa cubeba_ in nine provinces of China [35] and other regions of the world, our study revealed a higher diversity of tissue-related volatile metabolites, particularly in non-wood organs like seedsand leaves. Many earlier reports focused mainly on essential oil extracts from mature wood or bark tissues and often targeted only a limited number of compounds. In contrast, our untargeted GC-MS approach identified over 1666 volatile compounds across tissues, enabling detailed chemotaxonomic and functional comparisons. Furthermore, the integration of rOAV analysis and sensory annotation provides a deeper interpretation of aroma-active profiles, which is often absent in earlier regional reports. Therefore, this study provides an in-depth advancement in the volatile metabolomic characterization of _Phoebe_ species under subtropical East Asian environments, with methodological innovations that may be broadly applicable to other Lauraceae taxa and ecological contexts.