[Special culture mediums of breeding clones of Dendrobium officinale]

The explants were obtained from stem segments of hybrid combination of Dendrobium officinale germplasms (Zhejiang Yandang Mountain x Yunnan Guangnan). The screened culture mediums for buds induction and multiplication, which were 1/2MS + IBA 1.0 mg x L(-1) +6-BA 1.0 mg x L(-1) and 1/2MS + IBA 1.5 mg x L(-1) +6-BA 0.5 mg x L(-1) respectively, were applied to 159 germplasms of D. officinale from Zhejiang, Yunnan, Guangxi, Hunan, etc. The medium for axillary buds induction had universality with 94.3% induction rate. During buds multiplication, there were significant differences in proliferation effect among germplasms, and three proliferation forms i.e. single bud, multiple buds and protocorm were differentiated from different germplasms. The results showed that different germplasms of D. officinale had specific requirements for culture medium. Therefore, developing special culture medium for breeding clones of D. officinale is urgent and has important application values.