A Comparative Study of “Ophiopogon Root”, Enlarged Part of the Roots of Ophiopogon japonicas sensu lato (Asparagaceae)

Abstract

Ophiopogon japonicus (Thunb.) Ker Gawl. (Asparagaceae) is the original plant of “Ophiopogon Root” in The Japanese Pharmacopoeia 17th ed. (2016, p. 1881). However, O. japonicus s.lat. includes O. japonicus s.str., O. ohwii Okuyama and O. chekiangensis K. Kimura & Migo. Based on the investigations of the growing conditions and rhizome development, 139 individuals of O. japonicus s.lat. collected in Japan, were divided into three types, i.e., 60 individual of Oj type (gregarious, vertical and long creeping rhizome), 62 individuals of Oo type (tufted, vertical rhizome) and 17 individuals of Oc type (tufted and gregarious, vertical and long creeping rhizome). From the results of the cultivation experiments of the three types, it was found that the number, weight and size of the enlarged parts of the roots differed between the three types. In considering other characteristics together, these results lead to the conclusion that Oj, Oo and Oc types are identified as O. japonicus s.str., O. ohwii and O. chekiangensis, respectively. I propose that the original plant of “Ophiopogon Root” should be described as O. japonicus s.str., O. ohwii and O. chekiangensis in The Japanese Pharmacopoeia.