Effect of hormones on the seed germination of Bupleurum species

In Asia, Radix Bupleuri (Bupleurum spp. root) is an important medicine used for treating many diseases over the past 2000 years. However, its cultivation is difficult due to poor germination rates and loss of seedling viability shortly after seeding. In the present study, the effect of 6-benzyl aminopurine (6-BA), daminozide, gibberellin (GA3), paclobutrazol, uniconazole, and mepiquat chloride (MC) on the germination of seeds of ‘Zhongchai No. 3’, which is the newest released commercial variety of Bupleurum chinense DC in China was analyzed. Only GA3 was found to promote seed germination significantly, and its optimum concentration was 223.84 to 238.78 mg∙L-1. In addition, incubation with GA3 on the first day of germination was extremely important for seedling survival. This protocol could also be applied to ‘Zhonghongchai No. 1’ (B. scorzonerifolium Willd.) and ‘Hubei chaihu’ (B. chinense DC.). The combination of GA3 treatment and centralized incubation could be an efficient way to industrialize the production of secondary metabolites from Bupleurum species. Key words: Hormone, Bupleurum spp., germination, gibberellin (GA3).