| 摘要: | Traditional chinese medicine, pseudobulb of Bletilla formosana (Hayata) Schltr have anti-inflammatory, anti-liver tumor and anti-bacteria properties. The natural resource of B. formosana is seriously destructed by unlimited harvest. Sexual propagation may cause genetic variation, and affect the contents and composition of key medicinal compounds. This study aimed to screen the optimal medium and culture condition for propagation of B. formosana to establish an efficient plant regeneration pathway and induce in vitro pseudobulb formation. Protocorms were used for shoot induction with application of different concentration of BAP (0.5-2 mg/L), TDZ (0.5-2 mg/L) alone or combined with NAA (0-1 mg/L). The maximum shoot numbers (5.2±0.25 shoots/protocorm) induced from protocorms of B. formosana were observed in the MS basal medium supplemented with 2 mg/L TDZ and 0.5 mg/L NAA. Shoots were subcultured for rooting and MS basal medium supplemented with 2 mg/L NAA was found to be an optimal medium. Well-developed plantlets were acclimatized in plastic pots containing sphagnum moss with survival rate of 89.4%. In order to induce PLBs formation,protocorms and root explants were cultured in MS basal medium supplemented with 2, 4-D (0.1, 0.25, 0.5, 1 mg/L) and BAP (0.5, 1mg/L). However, after 8 weeks of culture, PLB formation from protocorms or roots explant to induce PLBs were not observed. Sucrose (20, 40 and 60 g/L), JA (0.25, 0.5, 1 mg/L), BAP (0.5, 1, 2 mg/L) and KIN (0.5, 1, 2 mg/L) were used to induce pseudobulb formation from 3-month old plantlet of B. formosana. The result showed JA, BAP and KIN were failed to enhance pseudobulb formation after 12 week of culture. High concentration of sucrose (40 and 60 g/L) inhibited the growth development of B. formosana. Cytokinin (BAP and KIN) enhanced multiple shoot induction in B. formosana. |
