トウキとイブキトウキとの交配種の作成とそのクローン増殖株の評価  [in Japanese] Evaluation of Intervarietal F_1 Hylrids of the Medicinal Plant, Angelica acutiloba, Clonally Propagated by Somatic Embryogenesis  [in Japanese]

For the purpose of breeding a new variety of Angelica acutiloba KITAGAWA, whose root is frequently used as a crude drug in the traditional Chinese medicine, "Kanpo," intervarietal crosses were made between two cultivated varieties, "Yamato Toki" (var. acutiloba) and "Ibuki Toki" (var. iwatensis). The F_1 hybrids propagated asexually by somatic embryogenesis were cultivated in the field together with the parental plants for one year. The growth of their root was recorded and some chemical constituents of their roots were assayed. The results showed that the clonal F_1 plants were superior to either of their parents not only in the root growth but also in the sucrose content of roots, suggesting the occurrence of heterosis. As regards the pharmacologically important secondary products, the amounts of anticholinergic (ligustilide and butylidenephthalide) and of antinociceptive (analgesic) compounds (falcarinol, falcarindiol, and choline) in the roots of the F1 clones were found to be intermediate between the amounts in the Yamato variety and those in the Ibuki variety. The results of the present study indicate the usefulness of intervarietal hybrid clones propagated by somatic embryogenesis in breeding interesting new varieties for medicinal use.