ABSTRACT
Objective To investigate the relationship between the root diameter of Angelica sinensis and its early bolting rate, and to decrease the bolting rate. Methods The seedling transplanting of A. sinensis with various root diameters was used to study the bolting rate and yield. Results Bolting plants can be observed in the field at June and the period from June to July is the bolting heyday. The bolting rate was the highest, up to 94.65%, in the treatment of root diameter ≥ 0.86 cm. However, it was only 1.63% in the treatment of root diameter ≤ 0.35 cm on Oct. 2nd. In the treatment of root diameter ≤ 0.35 cm, the seedling rate was only 33.62%, while in the treatment of root diameter ≥ 0.86 cm, the seedling rate was the highest, up to 95.75%, but the harvest seedling number was only 6 395 plant/hm2. In the treatment of root diameter of 0.46—0.55 cm, the harvest seedling number was 68 398 plant/hm2, which was significantly higher than other treatments. The highest yield appeared in the treatment of root diameter in 0.46—0.55 cm of transplanting seedling, the fresh and dry yields of A. sinensis were 5 717.58 kg/hm2 and 1 554.98 kg/hm2, respectively. Conclusion The seedlings with root diameter in the range of 0.46—0.65 cm should be selected to transplant in practice.