Callus induction, shoot proliferation and root regeneration of potato (Solanum tuberosumL.) stem node and leaf explants under long-day conditions

The present study investigated the effect of various concentrations and combinations of plant growth regulators on callus induction, shoot proliferation and root regeneration of three potato (Solanum tuberosum L.) cultivars by using potato nodal and leaf explants under long-day conditions. The minimum days for callus induction (8.33 d), the maximum callus formation percentage (87.50%), the largest callus diameter (1.90 cm) and the maximum callus weight (2.04 g) were recorded on 1.0 × Murashige and Skoog (MS) medium containing 3.0 mg L−1 benzyl amino purine (BAP) + 2.0 mg L−1 naphthalene acedic acid (NAA). Nodal explants demonstrated a better performance for callus induction compared to leaf segments. Nodal and leaf derived calli differentiated into shoot promordia when subcultured on MS media supplemented with different concentration of BAP, kinetin and thidiazuran as well as gibberellic acid (GA3) and NAA. The maximum shoot regeneration percentage (90.00%) and the maximum number of shoots (6.42) were obtained on 1.0 × MS medium containing 2.0 mg L−1 BAP + 0.25 mg L−1 GA3.