Somatic embryogenesis and organogenesis in neem (Azadirachta indica A Juss)

Methods for regeneration of plants in vitro from cotyledon and nucellus of Azadirachta indica are described. High frequency somatic embryogenesis was achieved from cotyledon explants in MS medium containing different concentrations of NAA. The embryoids developed into shoots when the embryogenic calli were transferred to cytokinin-supplemented media. However, the frequency of embryo conversion was very low. A high concentration of RA (0.5-2.5 mg/l) along with a comparatively low one (0.1-0.2 mg/l) of NAA induced cotyledon and nucellus explants to produced adventitious shoots. Shoot organogenesis best occurred when 2 mg/l BA and 0.2 mg/l NAA were used.