Abstract:The spore development and callus induction of Bryum dichotomum Hedw. in vitro culture were studied. The results showed that the spore germination and protonema development of B. dichotomum Hedw. were Bryum-type. The calli were successfully induced from protonema cultured on solid MS medium supplemented with 3.0 mg L-1 6-BA and 2.0 mg L-1 sodium silicate. The calli could be subcultured at long term on solid MS medium supplemented with 2.0 mg L-1 sodium silicate, 1.0 mg L-1 2,4-D and 1.0 mg L-1 6-BA. The fresh weight of calli cultured for 28 days was about 9.25 times to original weight under suspension culture, when incubated in liquid MS medium supplemented with 2.0 mg L-1 sodium silicate, 1.0 mg L-1 2,4-D and 1.0 mg L-1 6-BA.