The effect of plant growth regulators and explant types on callus induction and regeneration of Christ's thorn (Ziziphus spina christti (L.) Willd)

Christ’s thorn is one of important medicinal trees with many valued medicinal properties that in folklore medicinally have a special position in Iran. Nowadays, usage of biotechnology in breeding and proliferation of Christ’s thorn is prevalent and it is necessary to be improved the regeneration using optimize explants and hormone combinations. In order to evaluation the performance of node, leaf and root explants and the effect of different hormonal combinations on three phases of callus induction, regeneration and rooting of Christ’s thorn this study has been carried out in 2013 at biotechnology laboratory of Sari Agricultural Sciences and Natural Resources University. For callus induction, explants of aseptic seedlings were cultured on MS medium containing 2, 4-D, NAA, TDZ and BAP in three levels (0.5, 1, 2 mg/l). Then, produced calluses were taken on MS medium containing different levels of BAP, TDZ and Kin (1, 3, 5 mg/l) and for rooting of seedlings 1/2MS medium containing IBA and NAA (0.5, 1, 2 mg/l) were used. The treatments were arranged in factorial based on completely randomized design with four replications. The results showed that the highest rate of callogenesis was observed in leaf explants on MS medium containing 2, 4-D at concentrations of 0.5 mg/l (0 ± 10). While, the shoot regeneration obtained from callus produced on node explant by 5 mg/l Kin (10.03± 8.84) and 1mg/l TDZ (1.08±8.95) better as regards to callus produced on leaf and root explants. The rooting rate produced by IBA (90.6%) better than NAA (58%) at all concentrations of the hormone. According to the mentioned results Christ’s thorn than in vitro culture and regeneration show good response. The results can be used for various purposes, including reproduction and production of active ingredient in vitro culture.