Abstract:

A protocol for the induction of somatic embryogenesis via pseudobulbils from mature seeds of Rosa multiflora 'inermis 3' was established. The results showed that the primary pseudobulbils were obtained by using a two-stage procedure where excised seed cotyledons were incubated 30 days on the 1/2 Murashige and Skoog (MS) medium supplemented with 2, 4-D at 0.5~2 mg·L^-1 under the dark conditions for calli induction, and subsequently transferred to a 1/2 MS medium supplemented with TDZ at 5~20 mg·L^-1 under the light conditions for 20 days for pseudobulbils induction. The pseudobulbils were incubated 20 days on the induction medium supplemented with TDZ at 10 mg·L^-1 under the dark conditions and then transferred to the hormone-free medium supplemented with maltose instead of sucrose under light conditions for the secondary pseudobulbils and embryogenic calli induction. The pseudobulbils were maintained on the induction medium. The embryogenic calli developed into normal somatic embryos then plantlets. By this way, the pseudobulbils have been maintained for two years by far.

Key words: Rosa multiflora.Thunb., pseudobulbil, somatic embryogenesis, shoot regeneration