The regenerated plantlets of Acacia auriculiformis were obtained by the method of re-differentiation of the callus from the hypocotyls explants.The effects of plant regulator compositions on the induction of callus and the differentiation of adventitious buds in vitro culture were studied.The optimum medium for callus induction was MS medium containing 1.0 or 1.5 mg ·L-1 2,4-D and 0.5 mg ·L-1 KT and 100% the callus induction frequency was obtained.The optimum medium for re-differentiation of callus was MS medium containing 1.5 mg ·L-1 6-BA and 0.2 mg ·L-1 NAA and 84.7% of adventitious shoot regeneration frequency with 5.83 shoots per explants was obtained.In addition,the optimum medium for the adventitious buds induced from the hypocotyls explants without transferring the callus was MS medium containing 2.0 mg ·L-1 6-BA,0.1 mg ·L-1 NAA and 0.2 mg ·L-1 KT.Excised shoots were effectively elongated in MS medium without appending any hormones.Elongated shoots of 3.0 cm rooted when they were transferred to MS medium containing 0.1 mg ·L-1 IAA and 0.2 mg ·L-1 NAA after 30 days and developed into healthy plantlets,which resulted in a rooting rate of 85 %.The results of this study will facilitate the application of genetic transformation methods in A.auriculiformis.
