Metabolomic and transcriptomic analysis of the flavonoid biosynthesis pathway in Epimedium sagittatum (Sieb. et Zucc.) Maxim. from distinct locations oleh Shuyun Tian, Xingbin Lv, Mengxue Li, Qin Tang, Huilian Huang, Shengfu Hu, Fengqin Li, Yanqin Xu