[Reproductive biology of Dendrobium officinale (Orchidaceae) in Danxia landform]

To reveal the breeding system and endangered mechanism of Dendrobium officinale in Danxia landform.

The habitat, growth traits, floral phenology, propagation characteristic and status of resource destruction of D. officinale in Danxia landform were investigated.

The results showed that D. officinale grew in poor condition and the growth summit appeared in spring; its two- or three-years-old stems could be bloomed; higher seed-setting rate would be obtained when pollinated in time; the ovary began swelling after pollinated four or five days, until about 185 days later, the fruit matured; the seed-setting rate was very low (0.31%) in natural environment; only one clone was generated from one stem in a clump in annual.

D. officinale mainly reproduces by clonal propagation; over-collection is key factor which leads D. officinale to be in endangered status at present in this region.