Effect of Plant Growth Regulator Combination on Direct In Vitro Regeneration of Persian Lilac (Melia azedarach L.)

Abstract

Melia azedarach L. is an economically and medicinally important woody tree that is traditionally used for management of malaria, diabetes and skin diseases. This study was performed to survey the effects of different cytokinin combinations on direct in vitro regeneration of M. azedarach L. The explants were grown on semisolid Murashige and Skoog (MS) medium supplemented with a combination of BAP and TDZ (0, 0.5, 1 and 1.5 mg l−1) with IBA (0.1 mg l−1) and GA3 (0.5 mg l−1). The highest regenerated shoot number (6.5) was obtained on MS medium fortified with 0.1 mg l−1 TDZ plus 2 mg l−1 BAP in 4 weeks after culture. Also highest shoot length (8 cm) was obtained in 0.5 mg l−1 BAP plus TDZ (0.1, 0.25 and 0.5). In addition, the best rate of root induction (80%) and a number of roots per rooted shoot (2.3) were observed on 1/2 MS containing the 0.25 mg l−1 IBA. Regenerated plantlets were successfully acclimatized and hardened to culture room and then transferred to greenhouse; the plantlets survival rate was 90%. The present optimized regeneration protocol will serve as alternative approaches for Persian lilac conservation and large-scale propagation.