Abstract: By RP-HPLC method, diosgenin content of Dioscorea zingiberensis collected from 9 wild populations and 3 cultured populations in China were determined.The change of diosgenin content and weight of rhizoma were also tested after introduced from their native sites to Nanjing, Jiangsu Province and cultivated for a year.The result showed that diosgenin content in a year and the annual enlargement of root vary among different populations. D.zingiberensis of cultured populations has significant root enlargement and less diosgenin content than those of wild populations.In addition, the diosgenin content and its change are not correlated with water content.It concludes that the hereditary maintance of diosgenin content should be considered as the principal criterion in selection of cultivar.

Key words: Dioscorea zingiberensis, population, diosgenin, RP-HPLC