OBJECTIVETo set up the fittest medium and optimum condition for plantlets to form microtubers.

METHODPlant hormones, concentration of sucrose, active carbon and light time influenced formation of adventitious root and microtuber in vitro from plantlet of Rehmannia glutinosa (85-5).

RESULT AND CONCLUSIONThe plantlets were cultivated on the medium of microtuber induction after roots were induced on the 1/2MS medium with IBA 1 mg.L-1. The best medium was MS + 6-BA 2 mg.L-1 + NAA 0.1 mg.L-1 + Sucrose 5%. The fittest incubation temperature was 25 degrees C and the light length was (2,000-3,000 lx) 12 h.d-1. Active carbon and GA3 should not be added to the medium, which was not suitable for the induction of microtuber.