... trudng cd bd sung 0,5 - 1,0 mg/l NAA (naphthalene acetic acid). Khi l-phenyl- 3-( l,2,3-thiadiazol-5-yl)-urea (TDZ) dugc bd sung vao mdi tnrdng nudi cay d ndng dp 0,2 - 0,6 mg/l, cac cum choi ... phdt sinh hinh thdi, PGRs ' Author for correspondence: Tel: 8 4-6 3-3 831056; Fax: 8 4-6 3-3 831028; E-mail: duonstannhut&gmail. corn J J.J Tgp chi Cdng nghi Sinh hpc 1(1): 11 9-1 33, ... 1.0 mg 1"' NAA (naphthalene acetic acid). When l-phenyl- 3-( l,2, 3- thiadiazol-5-yl)-urea (TDZ) was added to culture medium at 0.2 - 0.6 mg 1"', shoot clusters regenerated directly...