Wild pistachio (Pistacia atlantica subsp. kurdica) is one of tree species that cover much of the west forest in Iran. In addition of industrial applications, this plant also has medicinal properties. The present study describes callus induction of the P. atlantica subsp. kurdica using seedling stem explants and the influence of different plant hormones like kinetin, BA, TDZ, 6-BAP on the growth of calli. To determine the best concentration and composition of growth regulators to induce callus in wild pistachio, 13 treatments were compared in a completely randomized experimental design with five replicates. Explants were taken from the 7-10 days of stem. Medium was used WPM containing 3% sucrose and 0.7% agar was cultured in vitro. The data collected for callus fresh and dry weights and callus percentage. Studies showed that concentrations of various different cytokinin and auxin in the callus produced a significant difference. The highest efficiency of callus formation was observed in the medium containing different concentration of 6-BAP individually. Appropriate protocol to optimize the production of callus in wild pistachio seedling stem was created using different combinations of hormones.
