Studies on cultivation of Angelica acutiloba using paper pot (Part 2): effect of difference in taproot base diameter of seedlings on growth after planting and quality of toki produced from paper pot seedlings.

By using Angelica acutiloba seedlings produced by short-period raising in paper pot (PP), we investigated the effect of taproot base diameter on the growth after planting and evaluated the quality of toki (, Angelicae Acutilobae Radix) produced from PP-grown seedlings (PT). In this study, PP-grown seedlings of seven classes which are sorted difference taproot base diameter (P1-P7) were transplanted. As a result, the survival rates were not less than 90% for P6 (taproot base diameter: 10.0-12.7 cm) and P7 (taproot base diameter: 12.8-17.3 cm), and the bolting rates were 20.5% and 24.1% for P6 and P7, respectively. The traditionally grown seedling (TS) showed the highest available harvest rate of 82.3%, followed by P6 (71.8%) and P7 (69.0%). P7 showed the highest fresh weight and dry weight per 1a (100 m2), followed by P6 and TS. However, PP-grown seedlings are prone to bolting, and it is expected the yield can be increased by preventing bolting. In addition, PT satisfied the regulations of JP17 in terms of, for example, dilute ethanol-soluble extract content, total ash content, and acid-insoluble ash content. It was also found that PT has a higher proportion of lateral roots with respect to the total weight than toki produced from traditionally grown seedlings (TT). The total (Z)-ligustilide contents were 0.07% in PT and 0.12% in TT. It was revealed that it is possible to produce toki that satisfies JP17 regulations; moreover, the period required for toki production was shortened by 6 months with PP-grown seedlings.