## 5 Conclusions  
In this study, 21 terpenoids were detected in sacred lotus and 105 genes involved in terpenoid synthesis were identified. WRKY, an important transcription factor, is highly correlated with the TPS gene family and might play an important regulatory role in the terpenoid synthesis process. This study illustrated the metabolic diversity of terpenoids in sacred lotus and provided a global overview of the gene expression profiles related with terpenoid biosynthesis in sacred lotus.  
**Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/molecules27144599/s1](https://www.mdpi.com/article/10.3390/molecules27144599/s1)]([https://www.mdpi.com/article/10.3390/molecules27144599/s1](https://www.mdpi.com/article/10.3390/molecules27144599/s1)), Figure S1: KEGG annotation of unigenes. The unigenes were divided into five branches according to the KEGG metabolic pathway: Cellular Processes, Environmental Information Processing, Genetic Information Processing, Metabolism, and Organismal Systems, Figure S2: Correlation analysis of WRKY TFs and released amounts of terpene compounds (Pearson correlation coefficient > 0.8). The circular nodes are WRKY TFs, the triangular nodes are terpen, the red line represents positive correlation, and the blue line represents negative correlation, Table S1: Sequencing output statistics, Table S2: Comparison efficiency statistics, Table S3: DEGS of groups, Table S4: The fpkm value of genes involved in terpened backbone synthesis, Table S5: The fpkm value of genes involved in terpenoid synthesis, Table S6: The fpkm value of genes annotated as WRKY transcription factors, Table S7: Primers used in qPCR.  
**Author Contributions:** Conceptualization, L.Q. and F.D.; methodology, N.Y.; software, C.Z.; validation, X.Z., J.T. and Z.W.; formal analysis, L.Q.; investigation, C.D.; resources, L.Y.; data curation, C.D.; writing--original draft preparation, L.Q.; writing--review and editing, C.D.; visualization, L.Y.; supervision, C.D.; project administration, C.D.; funding acquisition, C.D. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the China Postdoctoral Science Foundation (grant number 2020M672308), National Natural Science Foundation of China (grant number no. 31601366), Natural Science Foundation of Henan Province (grant number 202300410114), Cultivation Programme for Young Backbone Teachers in Henan University of Technology, the Innovative Funds Plan of Henan University of Technology (grant number 2020 ZKCJ23), and Program for Innovative Research Team (in Science and Technology) in University of Henan Province (grant number 19 IRTSTHN008).  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Raw sequencing data were deposited in the NCBI Bioproject database (accession number: PRJNA857167, [[https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857167](https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857167)]([https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857167](https://www.ncbi.nlm.nih.gov/bioproject/PRJNA857167)), accessed on 17 July 2022).  
**Conflicts of Interest:** The authors declare no conflict of interest.  
**Sample Availability:** Samples are not available.