2.5. Callus Induction
After sterilization, about 1cm2 leaf disc of the three
Jatropha accessions (Metema, Adami Tulu and Shewa Robit accession) were
transferred to callus induction media consisting of MS basal medium
supplemented with various combinations of 2, 4-D (0, 0.5, 1.0, 1.5 mg/L)
and BAP (0, 1.0, 1.5, 2.0 mg/L). Five leaf disc explants per jar were
used and each treatment was replicated five times. All the cultures were
incubated at 25 ± 2°C in darkness to promote callus formation and
discourage greening of the callus. The percentage proportion of callus
induction on leaf discs was evaluated at an interval of four weeks after
inoculation of explant.