[Discrimination of varieties of peony in Huangqin decoction]

By studying the varieties of peony and analyzing the prescription of Huangqin decoction, the authors explored the differences between Paeoniae Radix Alba and Radix Paeoniae Rubra in varieties, origin, processing method and clinical efficacy and compare their efficacies to define Paeoniae Radix Alba or Paeoniae Radix Rubra in Huangqin decoction recorded in Treatise on Febrile Diseases. In the study, the authors clarified the development and change of the variety in various historical periods according to the earliest ancient herbal book recording the variety and the development sequence of main herbs, and made clear the relations between Paeoniae Radix Alba and Paeoniae Radix Rubra. The modern application of Paeoniae Radix Alba started in the Song Dynasty. Although it was processed in different ways from Paeoniae radix Rubra, they shared the same original plant varieties. On the basis of the historical origin, botanical origin, producing place and processing method, the authors made clear the evolvement of peony varieties, discussed and analyzed the developments and changes for the combined to the separate administration of Paeoniae Radix Alba and Paeoniae Radix Rubra and defined the peony variety in Huangqin decoction. Through the textual research on ancient herbal books, the authors confirmed that more than 2 000 years ago, Paeoniae Radix Alba didn't appear when Treatise on Febrile Diseases was written. According to the records in Miscellaneous Records of Famous Physicians that "its roots were collected and dried in February and August", it was inferred that the use of Paeoniae Radix Rubra conformed to the historical facts.