A novel method of organogenesis in neem (Azadirachta indica A. Juss.) from unfertilized ovaries is described. The Murashige and Skoog’s (MS) medium with 9 % sucrose, 1 µM 2,4-dichlorophenoxyacetic
acid (2,4-D) and 5 µM 6-benzylaminopurine (BAP) was the best for callus induction from unfertilized ovaries. However, further
proliferation of callus occurred better on MS medium supplemented with 0.5
... [Show full abstract] µM 2,4-D either alone or in combination with 4.5
µM kinetin. Maximum shoot regeneration (78 %) was observed when calli, induced from ovaries of 4 mm size flower buds and proliferating
on MS + 0.5 µM 2,4-D, were subcultured to MS medium containing 5 µM BAP. Histological analysis revealed that 4 mm sized flower
bud corresponds to a 2-nucleate stage of embryo sac. The shoots were then multiplied by forced axillary branching on MS medium
supplemented with 1.0 µM BAP and 250 mg dm−3 casein hydrolysate. The shoots could be rooted on 1/4 strength MS medium supplemented with 0.5 µM indole-3-butyric acid (IBA)
at a frequency of 79 %. Cytological analysis by root tip squash preparations revealed that all the plantlets were diploids.
These plants were subsequently hardened and established in soil with transplantation rate of 81.8 %.