*4.4. Statistical Analysis*

SPSS (version 24.0;(IBM, Chicago, IL, USA)) was used to perform a t-test and Metabo-Analyst 5.0 (http://www.metaboanalyst.ca/, accessed on 5 March 2021) was used for principal component analysis (PCA) and hierarchical cluster analysis (HCA) using Pearson correlations for the metabolites detected in roots, stems, and leaves of *S. baicalensis* seedlings treated with different LED lights. The resolution of the resulting figures was improved using Adobe Illustrator.
