Effect of explant source and growth regulators on in vitro callus induction and organogenesis of Melia azedarach L. trees

Melia azedarach L. is one of the important plants because it’s a good source of natural compounds that have insecticide and antimicrobial effect. The main aim of this research is to investigate the effect of explants source and plant growth regulators on in vitro callus induction and regeneration of organs from it. Callus was induced from nodes, internodes from one-year-old seedlings and seeds of Melia plant by culturing them on MS medium supplemented with α-naphthalene acetic acid (NAA) 0.0, 0.1, 0.2, 0.3, or 0.4 mg/L and 6- benzyl adenine (BA) 0.0, 1.0, 2.0, 3.0, or 4.0 mg/L, then shoot regeneration from callus was occurred. Results showed that there was a different response from explants towards callus induction and adventitious shoots formation according to plant growth regulators combination. Seeds gave superior percentage for callus induction 24.4% compared with node and internode 15.6, 12.8% respectively. Combination of 0.3 mg/L NAA + 3.0 mg/L BA was the best for callus induction in all explants 86.6% . Shoot regeneration was achieved in 0.3 mg/L NAA + 4.0 mg/L BA and 0.4 mg/L NAA + 4.0 mg/L BA for callus from seeds and internodes respectively, while the combination 0.3 mg/L NAA + 3.0 mg/L BA or 0.4 mg/L NAA + 3.0 mg/L BA was the best for node callus. The shoots were rooted well in MS + 0.25 mg/L NAA . Rooted plantlets were acclimatized in small plastic pots filled with peat moss: river soil (1 :1 v/v ), then transferred to the soil.