Abstract: In order to protect and utilize effectively the endangered species Sinojackia xylocarpa Hu, orthogonal testswere designed to get the effects of plant hormones on the multip lication, growth and rooting of the species tube-shoots. A study was conducted on in vitro culture and plant regeneration of Sinojackia xylocarpa Hu with the nodal segments or apical buds excised from the newly-grown shoots of the five-year-old elite maternal plant. Results showed that the modified MS supplemented with BA 1.0 mg/L + TDZ 0.05 mg/L +
IBA 0.05 mg/L +Vitamin C 50 mg/L + 3% Sucrose was optimal for the tube-shoot multiplication while the modifiedMS with BA 0.5 mg/L + TDZ 0.05 mg/L + IBA 0.1 mg/L +Vitamin C 50 mg/L + 3% Sucrose was suitable for the vigorous growth. 1 /2MS with IBA 0.5 mg/L +NAA 0.3 mg/L +Vitamin C 100 mg/L + 2%
Sucrose op timized the tube-shoot rooting induction. The plantlets with root were transplanted into the substrate containing vermiculate, pearlite and peat, 6∶3∶1 ( v/v). At 20 - 30℃, relative humidity of 85% - 90% for 15 - 20 days, the plantlets could grow well, with the survival up to 92% after 35 days’ transplanting.

Key words: Sinojackia xylocarpa Hu, In vitro culture, Plant hormones, Vitamin C